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• Stumbling Through: Visual Studio 2010 (Part I)

  Ive spent the better part of the last two years doing nothing but K2 workflow development, which until very recently could only be done in Visual Studio 2005 so I am a bit behind the times. I seem to have skipped over using Visual Studio 2008 entirely, and I am now ready to stumble through all that Ive missed. Not that I will abandon my K2 ramblings, but I need to get back to some of the other technologies I am passionate about but havent had the option of working with them on a day-to-day basis as I have with K2 blackpearl. Specifically, I am going to be focusing my efforts on what is new in the Entity Framework and WPF in Visual Studio 2010, though you have to keep in mind that since I have skipped VS 2008, I may be giving VS 2010 credit for things that really have been around for a while (hey, if I havent seen it, it is new to me!). I have the following simple goals in mind for this exercise: Entity Framework Model an inherited class Entity Framework Model a lookup entity WPF Bind a list of entities WPF - on selection of an entity in the bound list, display values of the selected entity WPF For the lookup field, provide a dropdown of potential values to lookup All of these goals must be accomplished using as little code as possible, relying on the features we get out of the box in Visual Studio 2010. This isnt going to be rocket science here, Im not even looking to get or save this data from/to a data source, but I gotta start somewhere and hopefully it will grow into something more interesting. For this exercise, I am going to try to model some fictional data about football players and personnel (maybe turning this into some sort of NFL simulation game if I lose my job and can play with this all day), so Ill start with a Person class that has a name property, and extend that with a Player class to include a Position lookup property. The idea is that a Person can be a Player, Coach or whatever other personnel type may be associated with a football team but well only flesh out the Player aspect of a person for this. So to get started, I fired up Visual Studio 2010 and created a new WPF Application: To this project, I added a new ADO.NET Entity Data Model named PlayerModel (for now, not sure what will be an appropriate name so this may be revisited): I chose for it to be an empty model, as I dont have a database designed for this yet: Using the toolbox, I dragged out an entity for each of the items we identified earlier: Person, Player and Position, and gave them some simple properties (note that I kept the default Id property for each of them): Now to figure out how to link these things together the way I want to first, lets try to tell it that Player extends Person. I see that Inheritance is one of the items in the toolbox, but I cant seem to drag it out anywhere onto the canvas. However, when I right-click an element, I get the option to Add Inheritance to it, which gives us exactly what we want: Ok, now that we have that, how do we tell it that each player has a position? Well, despite association being in the toolbox, I have learned that you cant just drag and drop those elements so I right click Player and select Add -> Association to get the following dialog: I see the option here to Add foreign key properties to my entities Ive read somewhere this this is a new and highly-sought after feature so Ill see what it does. Selecting it includes a PositionId on the Player element for me, which seems pretty database-centric and I would like to see if I can live without it for now given that we also got the Position property out of this association. Ill bring it back into the fold if it ends up being useful later. Here is what we end up with now: Trying to compile this resulted in an error stating that the Player entity cannot have an Id, because the Person element it extends already has a property named Id. Makes sense, so I remove it and compile again. Success, but with a warning but success is a good thing so Ill pretend I didnt see that warning for now. It probably has to do with the fact that my Player entity is now pretty useless as it doesnt have any non-navigation properties. So things seem to match what we are going for, great now what the heck do we do with this? Lets switch gears and see what we get for free dealing with this model from the UI. Lets open up the MainWindow.xaml and see if we can connect to our entities as a data source. Hey, whats this? Have you read my mind, Visual Studio? Our entities are already listed in the Data Sources panel: I do notice, however, that our Player entity is missing. Is this due to that compilation warning? Ill add a bogus property to our player entity just to see if that is the case no, still no love. The warning reads: Error 2062: No mapping specified for instances of the EntitySet and AssociationSet in the EntityContainer PlayerModelContainer. Well if everything worked without any issues, then I wouldnt be stumbling through at all, so lets get to the bottom of this. My good friend google indicates that the warning is due to the model not being tied up to a database. Hmmm, so why dont Players show up in my data sources? A little bit of drill-down shows that they are, in fact, exposed under Positions: Well now that isnt quite what I want. While you could get to players through a position, it shouldnt be that way exclusively. Oh well, I can ignore that for now lets drag Players out onto the canvas after selecting List from the dropdown: Hey, what the heck? I wanted a list not a listview. Get rid of that list view that was just dropped, drop in a listbox and then drop the Players entity into it. That will bind it for us. Of course, there isnt any data to show, which brings us to the really hacky part of all this and that is to stuff some test data into our view source without actually getting it from any data source. To do this through code, we need to grab a reference to the positionsPlayersViewSource resource that was created for us when we dragged out our Players entity. We then set the source of that reference equal to a populated list of Players.  Well add a couple of players that way as well as a few positions via the positionsViewSource resource, and Ill ensure that each player has a position specified.  Ultimately, the code looks like this: System.Windows.Data.CollectionViewSource positionViewSource = ((System.Windows.Data.CollectionViewSource)(this.FindResource("positionsViewSource")));             List<Position> positions = new List<Position>();             Position newPosition = new Position();             newPosition.Id = 0;             newPosition.Name = "WR";             positions.Add(newPosition);             newPosition = new Position();             newPosition.Id = 1;             newPosition.Name = "RB";             positions.Add(newPosition);             newPosition = new Position();             newPosition.Id = 2;             newPosition.Name = "QB";             positions.Add(newPosition);             positionViewSource.Source = positions;             System.Windows.Data.CollectionViewSource playerViewSource = ((System.Windows.Data.CollectionViewSource)(this.FindResource("positionsPlayersViewSource")));             List<Player> players = new List<Player>();             Player newPlayer = new Player();             newPlayer.Id = 0;             newPlayer.Name = "Test Dude";             newPlayer.Position = positions[0];             players.Add(newPlayer);             newPlayer = new Player();             newPlayer.Id = 1;             newPlayer.Name = "Test Dude II";             newPlayer.Position = positions[1];             players.Add(newPlayer);             newPlayer = new Player();             newPlayer.Id = 2;             newPlayer.Name = "Test Dude III";             newPlayer.Position = positions[2];             players.Add(newPlayer);             playerViewSource.Source = players; Now that our views are being loaded with data, we can go about tying things together visually. Drop a text box (to show the selected players name) and a combo box (to show the selected players position). Drag the Positions entity from the data sources panel to the combo box to wire it up to the positions view source. Click the text box that was dragged, and find its Text property in the properties pane. There is a little glyph next to it that displays Advanced Properties when hovered over click this and then select Apply Data Binding. In the dialog that appears, we can select the current players name as the value to bind to: Similarly, we can wire up the combo boxs SelectedItem value to the current players position: When the application is executed and we navigate through the various players, we automatically get their name and position bound to the appropriate fields: All of this was accomplished with no code save for loading the test data, and I might add, it was pretty intuitive to do so via the drag and drop of entities straight from the data sources panel. So maybe all of this was old hat to you, but I was very impressed with this experience and I look forward to stumbling through the caveats of doing more complex data modeling and binding in this fashion. Next up, I suppose, will be figuring out how to get the entities to get real data from a data source instead of stuffing it with test data as well as trying to figure out why Players ended up being under Positions in the data sources panel.Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• .NET Code Evolution

  - by Alois Kraus

  Originally posted on: http://geekswithblogs.net/akraus1/archive/2013/07/24/153504.aspxAt my day job I do look at a lot of code written by other people. Most of the code is quite good and some is even a masterpiece. And there is also code which makes you think WTF… oh it was written by me. Hm not so bad after all. There are many excuses reasons for bad code. Most often it is time pressure followed by not enough ambition (who cares) or insufficient training. Normally I do care about code quality quite a lot which makes me a (perceived) slow worker who does write many tests and refines the code quite a lot because of the design deficiencies. Most of the deficiencies I do find by putting my design under stress while checking for invariants. It does also help a lot to step into the code with a debugger (sometimes also Windbg). I do this much more often when my tests are red. That way I do get a much better understanding what my code really does and not what I think it should be doing. This time I do want to show you how code can evolve over the years with different .NET Framework versions. Once there was  time where .NET 1.1 was new and many C++ programmers did switch over to get rid of not initialized pointers and memory leaks. There were also nice new data structures available such as the Hashtable which is fast lookup table with O(1) time complexity. All was good and much code was written since then. At 2005 a new version of the .NET Framework did arrive which did bring many new things like generics and new data structures. The “old” fashioned way of Hashtable were coming to an end and everyone used the new Dictionary<xx,xx> type instead which was type safe and faster because the object to type conversion (aka boxing) was no longer necessary. I think 95% of all Hashtables and dictionaries use string as key. Often it is convenient to ignore casing to make it easy to look up values which the user did enter. An often followed route is to convert the string to upper case before putting it into the Hashtable. Hashtable Table = new Hashtable(); void Add(string key, string value) { Table.Add(key.ToUpper(), value); } This is valid and working code but it has problems. First we can pass to the Hashtable a custom IEqualityComparer to do the string matching case insensitive. Second we can switch over to the now also old Dictionary type to become a little faster and we can keep the the original keys (not upper cased) in the dictionary. Dictionary<string, string> DictTable = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase); void AddDict(string key, string value) { DictTable.Add(key, value); } Many people do not user the other ctors of Dictionary because they do shy away from the overhead of writing their own comparer. They do not know that .NET has for strings already predefined comparers at hand which you can directly use. Today in the many core area we do use threads all over the place. Sometimes things break in subtle ways but most of the time it is sufficient to place a lock around the offender. Threading has become so mainstream that it may sound weird that in the year 2000 some guy got a huge incentive for the idea to reduce the time to process calibration data from 12 hours to 6 hours by using two threads on a dual core machine. Threading does make it easy to become faster at the expense of correctness. Correct and scalable multithreading can be arbitrarily hard to achieve depending on the problem you are trying to solve. Lets suppose we want to process millions of items with two threads and count the processed items processed by all threads. A typical beginners code might look like this: int Counter; void IJustLearnedToUseThreads() { var t1 = new Thread(ThreadWorkMethod); t1.Start(); var t2 = new Thread(ThreadWorkMethod); t2.Start(); t1.Join(); t2.Join(); if (Counter != 2 * Increments) throw new Exception("Hmm " + Counter + " != " + 2 * Increments); } const int Increments = 10 * 1000 * 1000; void ThreadWorkMethod() { for (int i = 0; i < Increments; i++) { Counter++; } } It does throw an exception with the message e.g. “Hmm 10.222.287 != 20.000.000” and does never finish. The code does fail because the assumption that Counter++ is an atomic operation is wrong. The ++ operator is just a shortcut for Counter = Counter + 1 This does involve reading the counter from a memory location into the CPU, incrementing value on the CPU and writing the new value back to the memory location. When we do look at the generated assembly code we will see only inc dword ptr [ecx+10h] which is only one instruction. Yes it is one instruction but it is not atomic. All modern CPUs have several layers of caches (L1,L2,L3) which try to hide the fact how slow actual main memory accesses are. Since cache is just another word for redundant copy it can happen that one CPU does read a value from main memory into the cache, modifies it and write it back to the main memory. The problem is that at least the L1 cache is not shared between CPUs so it can happen that one CPU does make changes to values which did change in meantime in the main memory. From the exception you can see we did increment the value 20 million times but half of the changes were lost because we did overwrite the already changed value from the other thread. This is a very common case and people do learn to protect their  data with proper locking.   void Intermediate() { var time = Stopwatch.StartNew(); Action acc = ThreadWorkMethod_Intermediate; var ar1 = acc.BeginInvoke(null, null); var ar2 = acc.BeginInvoke(null, null); ar1.AsyncWaitHandle.WaitOne(); ar2.AsyncWaitHandle.WaitOne(); if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Intermediate did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Intermediate() { for (int i = 0; i < Increments; i++) { lock (this) { Counter++; } } } This is better and does use the .NET Threadpool to get rid of manual thread management. It does give the expected result but it can result in deadlocks because you do lock on this. This is in general a bad idea since it can lead to deadlocks when other threads use your class instance as lock object. It is therefore recommended to create a private object as lock object to ensure that nobody else can lock your lock object. When you read more about threading you will read about lock free algorithms. They are nice and can improve performance quite a lot but you need to pay close attention to the CLR memory model. It does make quite weak guarantees in general but it can still work because your CPU architecture does give you more invariants than the CLR memory model. For a simple counter there is an easy lock free alternative present with the Interlocked class in .NET. As a general rule you should not try to write lock free algos since most likely you will fail to get it right on all CPU architectures. void Experienced() { var time = Stopwatch.StartNew(); Task t1 = Task.Factory.StartNew(ThreadWorkMethod_Experienced); Task t2 = Task.Factory.StartNew(ThreadWorkMethod_Experienced); t1.Wait(); t2.Wait(); if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Experienced did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Experienced() { for (int i = 0; i < Increments; i++) { Interlocked.Increment(ref Counter); } } Since time does move forward we do not use threads explicitly anymore but the much nicer Task abstraction which was introduced with .NET 4 at 2010. It is educational to look at the generated assembly code. The Interlocked.Increment method must be called which does wondrous things right? Lets see: lock inc dword ptr [eax] The first thing to note that there is no method call at all. Why? Because the JIT compiler does know very well about CPU intrinsic functions. Atomic operations which do lock the memory bus to prevent other processors to read stale values are such things. Second: This is the same increment call prefixed with a lock instruction. The only reason for the existence of the Interlocked class is that the JIT compiler can compile it to the matching CPU intrinsic functions which can not only increment by one but can also do an add, exchange and a combined compare and exchange operation. But be warned that the correct usage of its methods can be tricky. If you try to be clever and look a the generated IL code and try to reason about its efficiency you will fail. Only the generated machine code counts. Is this the best code we can write? Perhaps. It is nice and clean. But can we make it any faster? Lets see how good we are doing currently. Level Time in s IJustLearnedToUseThreads Flawed Code Intermediate 1,5 (lock) Experienced 0,3 (Interlocked.Increment) Master 0,1 (1,0 for int[2]) That lock free thing is really a nice thing. But if you read more about CPU cache, cache coherency, false sharing you can do even better. int[] Counters = new int[12]; // Cache line size is 64 bytes on my machine with an 8 way associative cache try for yourself e.g. 64 on more modern CPUs void Master() { var time = Stopwatch.StartNew(); Task t1 = Task.Factory.StartNew(ThreadWorkMethod_Master, 0); Task t2 = Task.Factory.StartNew(ThreadWorkMethod_Master, Counters.Length - 1); t1.Wait(); t2.Wait(); Counter = Counters[0] + Counters[Counters.Length - 1]; if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Master did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Master(object number) { int index = (int) number; for (int i = 0; i < Increments; i++) { Counters[index]++; } } The key insight here is to use for each core its own value. But if you simply use simply an integer array of two items, one for each core and add the items at the end you will be much slower than the lock free version (factor 3). Each CPU core has its own cache line size which is something in the range of 16-256 bytes. When you do access a value from one location the CPU does not only fetch one value from main memory but a complete cache line (e.g. 16 bytes). This means that you do not pay for the next 15 bytes when you access them. This can lead to dramatic performance improvements and non obvious code which is faster although it does have many more memory reads than another algorithm. So what have we done here? We have started with correct code but it was lacking knowledge how to use the .NET Base Class Libraries optimally. Then we did try to get fancy and used threads for the first time and failed. Our next try was better but it still had non obvious issues (lock object exposed to the outside). Knowledge has increased further and we have found a lock free version of our counter which is a nice and clean way which is a perfectly valid solution. The last example is only here to show you how you can get most out of threading by paying close attention to your used data structures and CPU cache coherency. Although we are working in a virtual execution environment in a high level language with automatic memory management it does pay off to know the details down to the assembly level. Only if you continue to learn and to dig deeper you can come up with solutions no one else was even considering. I have studied particle physics which does help at the digging deeper part. Have you ever tried to solve Quantum Chromodynamics equations? Compared to that the rest must be easy ;-). Although I am no longer working in the Science field I take pride in discovering non obvious things. This can be a very hard to find bug or a new way to restructure data to make something 10 times faster. Now I need to get some sleep ….

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• Using FiddlerCore to capture HTTP Requests with .NET

  - by Rick Strahl

  Over the last few weeks I’ve been working on my Web load testing utility West Wind WebSurge. One of the key components of a load testing tool is the ability to capture URLs effectively so that you can play them back later under load. One of the options in WebSurge for capturing URLs is to use its built-in capture tool which acts as an HTTP proxy to capture any HTTP and HTTPS traffic from most Windows HTTP clients, including Web Browsers as well as standalone Windows applications and services. To make this happen, I used Eric Lawrence’s awesome FiddlerCore library, which provides most of the functionality of his desktop Fiddler application, all rolled into an easy to use library that you can plug into your own applications. FiddlerCore makes it almost too easy to capture HTTP content! For WebSurge I needed to capture all HTTP traffic in order to capture the full HTTP request – URL, headers and any content posted by the client. The result of what I ended up creating is this semi-generic capture form: In this post I’m going to demonstrate how easy it is to use FiddlerCore to build this HTTP Capture Form.  If you want to jump right in here are the links to get Telerik’s Fiddler Core and the code for the demo provided here. FiddlerCore Download FiddlerCore on NuGet Show me the Code (WebSurge Integration code from GitHub) Download the WinForms Sample Form West Wind Web Surge (example implementation in live app) Note that FiddlerCore is bound by a license for commercial usage – see license.txt in the FiddlerCore distribution for details. Integrating FiddlerCore FiddlerCore is a library that simply plugs into your application. You can download it from the Telerik site and manually add the assemblies to your project, or you can simply install the NuGet package via:       PM> Install-Package FiddlerCore The library consists of the FiddlerCore.dll as well as a couple of support libraries (CertMaker.dll and BCMakeCert.dll) that are used for installing SSL certificates. I’ll have more on SSL captures and certificate installation later in this post. But first let’s see how easy it is to use FiddlerCore to capture HTTP content by looking at how to build the above capture form. Capturing HTTP Content Once the library is installed it’s super easy to hook up Fiddler functionality. Fiddler includes a number of static class methods on the FiddlerApplication object that can be called to hook up callback events as well as actual start monitoring HTTP URLs. In the following code directly lifted from WebSurge, I configure a few filter options on Form level object, from the user inputs shown on the form by assigning it to a capture options object. In the live application these settings are persisted configuration values, but in the demo they are one time values initialized and set on the form. Once these options are set, I hook up the AfterSessionComplete event to capture every URL that passes through the proxy after the request is completed and start up the Proxy service:void Start() { if (tbIgnoreResources.Checked) CaptureConfiguration.IgnoreResources = true; else CaptureConfiguration.IgnoreResources = false; string strProcId = txtProcessId.Text; if (strProcId.Contains('-')) strProcId = strProcId.Substring(strProcId.IndexOf('-') + 1).Trim(); strProcId = strProcId.Trim(); int procId = 0; if (!string.IsNullOrEmpty(strProcId)) { if (!int.TryParse(strProcId, out procId)) procId = 0; } CaptureConfiguration.ProcessId = procId; CaptureConfiguration.CaptureDomain = txtCaptureDomain.Text; FiddlerApplication.AfterSessionComplete += FiddlerApplication_AfterSessionComplete; FiddlerApplication.Startup(8888, true, true, true); } The key lines for FiddlerCore are just the last two lines of code that include the event hookup code as well as the Startup() method call. Here I only hook up to the AfterSessionComplete event but there are a number of other events that hook various stages of the HTTP request cycle you can also hook into. Other events include BeforeRequest, BeforeResponse, RequestHeadersAvailable, ResponseHeadersAvailable and so on. In my case I want to capture the request data and I actually have several options to capture this data. AfterSessionComplete is the last event that fires in the request sequence and it’s the most common choice to capture all request and response data. I could have used several other events, but AfterSessionComplete is one place where you can look both at the request and response data, so this will be the most common place to hook into if you’re capturing content. The implementation of AfterSessionComplete is responsible for capturing all HTTP request headers and it looks something like this:private void FiddlerApplication_AfterSessionComplete(Session sess) { // Ignore HTTPS connect requests if (sess.RequestMethod == "CONNECT") return; if (CaptureConfiguration.ProcessId > 0) { if (sess.LocalProcessID != 0 && sess.LocalProcessID != CaptureConfiguration.ProcessId) return; } if (!string.IsNullOrEmpty(CaptureConfiguration.CaptureDomain)) { if (sess.hostname.ToLower() != CaptureConfiguration.CaptureDomain.Trim().ToLower()) return; } if (CaptureConfiguration.IgnoreResources) { string url = sess.fullUrl.ToLower(); var extensions = CaptureConfiguration.ExtensionFilterExclusions; foreach (var ext in extensions) { if (url.Contains(ext)) return; } var filters = CaptureConfiguration.UrlFilterExclusions; foreach (var urlFilter in filters) { if (url.Contains(urlFilter)) return; } } if (sess == null || sess.oRequest == null || sess.oRequest.headers == null) return; string headers = sess.oRequest.headers.ToString(); var reqBody = sess.GetRequestBodyAsString(); // if you wanted to capture the response //string respHeaders = session.oResponse.headers.ToString(); //var respBody = session.GetResponseBodyAsString(); // replace the HTTP line to inject full URL string firstLine = sess.RequestMethod + " " + sess.fullUrl + " " + sess.oRequest.headers.HTTPVersion; int at = headers.IndexOf("\r\n"); if (at < 0) return; headers = firstLine + "\r\n" + headers.Substring(at + 1); string output = headers + "\r\n" + (!string.IsNullOrEmpty(reqBody) ? reqBody + "\r\n" : string.Empty) + Separator + "\r\n\r\n"; BeginInvoke(new Action<string>((text) => { txtCapture.AppendText(text); UpdateButtonStatus(); }), output); } The code starts by filtering out some requests based on the CaptureOptions I set before the capture is started. These options/filters are applied when requests actually come in. This is very useful to help narrow down the requests that are captured for playback based on options the user picked. I find it useful to limit requests to a certain domain for captures, as well as filtering out some request types like static resources – images, css, scripts etc. This is of course optional, but I think it’s a common scenario and WebSurge makes good use of this feature. AfterSessionComplete like other FiddlerCore events, provides a Session object parameter which contains all the request and response details. There are oRequest and oResponse objects to hold their respective data. In my case I’m interested in the raw request headers and body only, as you can see in the commented code you can also retrieve the response headers and body. Here the code captures the request headers and body and simply appends the output to the textbox on the screen. Note that the Fiddler events are asynchronous, so in order to display the content in the UI they have to be marshaled back the UI thread with BeginInvoke, which here simply takes the generated headers and appends it to the existing textbox test on the form. As each request is processed, the headers are captured and appended to the bottom of the textbox resulting in a Session HTTP capture in the format that Web Surge internally supports, which is basically raw request headers with a customized 1st HTTP Header line that includes the full URL rather than a server relative URL. When the capture is done the user can either copy the raw HTTP session to the clipboard, or directly save it to file. This raw capture format is the same format WebSurge and also Fiddler use to import/export request data. While this code is application specific, it demonstrates the kind of logic that you can easily apply to the request capture process, which is one of the reasonsof why FiddlerCore is so powerful. You get to choose what content you want to look up as part of your own application logic and you can then decide how to capture or use that data as part of your application. The actual captured data in this case is only a string. The user can edit the data by hand or in the the case of WebSurge, save it to disk and automatically open the captured session as a new load test. Stopping the FiddlerCore Proxy Finally to stop capturing requests you simply disconnect the event handler and call the FiddlerApplication.ShutDown() method:void Stop() { FiddlerApplication.AfterSessionComplete -= FiddlerApplication_AfterSessionComplete; if (FiddlerApplication.IsStarted()) FiddlerApplication.Shutdown(); } As you can see, adding HTTP capture functionality to an application is very straight forward. FiddlerCore offers tons of features I’m not even touching on here – I suspect basic captures are the most common scenario, but a lot of different things can be done with FiddlerCore’s simple API interface. Sky’s the limit! The source code for this sample capture form (WinForms) is provided as part of this article. Adding Fiddler Certificates with FiddlerCore One of the sticking points in West Wind WebSurge has been that if you wanted to capture HTTPS/SSL traffic, you needed to have the full version of Fiddler and have HTTPS decryption enabled. Essentially you had to use Fiddler to configure HTTPS decryption and the associated installation of the Fiddler local client certificate that is used for local decryption of incoming SSL traffic. While this works just fine, requiring to have Fiddler installed and then using a separate application to configure the SSL functionality isn’t ideal. Fortunately FiddlerCore actually includes the tools to register the Fiddler Certificate directly using FiddlerCore. Why does Fiddler need a Certificate in the first Place? Fiddler and FiddlerCore are essentially HTTP proxies which means they inject themselves into the HTTP conversation by re-routing HTTP traffic to a special HTTP port (8888 by default for Fiddler) and then forward the HTTP data to the original client. Fiddler injects itself as the system proxy in using the WinInet Windows settings  which are the same settings that Internet Explorer uses and that are configured in the Windows and Internet Explorer Internet Settings dialog. Most HTTP clients running on Windows pick up and apply these system level Proxy settings before establishing new HTTP connections and that’s why most clients automatically work once Fiddler – or FiddlerCore/WebSurge are running. For plain HTTP requests this just works – Fiddler intercepts the HTTP requests on the proxy port and then forwards them to the original port (80 for HTTP and 443 for SSL typically but it could be any port). For SSL however, this is not quite as simple – Fiddler can easily act as an HTTPS/SSL client to capture inbound requests from the server, but when it forwards the request to the client it has to also act as an SSL server and provide a certificate that the client trusts. This won’t be the original certificate from the remote site, but rather a custom local certificate that effectively simulates an SSL connection between the proxy and the client. If there is no custom certificate configured for Fiddler the SSL request fails with a certificate validation error. The key for this to work is that a custom certificate has to be installed that the HTTPS client trusts on the local machine. For a much more detailed description of the process you can check out Eric Lawrence’s blog post on Certificates. If you’re using the desktop version of Fiddler you can install a local certificate into the Windows certificate store. Fiddler proper does this from the Options menu: This operation does several things: It installs the Fiddler Root Certificate It sets trust to this Root Certificate A new client certificate is generated for each HTTPS site monitored Certificate Installation with FiddlerCore You can also provide this same functionality using FiddlerCore which includes a CertMaker class. Using CertMaker is straight forward to use and it provides an easy way to create some simple helpers that can install and uninstall a Fiddler Root certificate:public static bool InstallCertificate() { if (!CertMaker.rootCertExists()) { if (!CertMaker.createRootCert()) return false; if (!CertMaker.trustRootCert()) return false; } return true; } public static bool UninstallCertificate() { if (CertMaker.rootCertExists()) { if (!CertMaker.removeFiddlerGeneratedCerts(true)) return false; } return true; } InstallCertificate() works by first checking whether the root certificate is already installed and if it isn’t goes ahead and creates a new one. The process of creating the certificate is a two step process – first the actual certificate is created and then it’s moved into the certificate store to become trusted. I’m not sure why you’d ever split these operations up since a cert created without trust isn’t going to be of much value, but there are two distinct steps. When you trigger the trustRootCert() method, a message box will pop up on the desktop that lets you know that you’re about to trust a local private certificate. This is a security feature to ensure that you really want to trust the Fiddler root since you are essentially installing a man in the middle certificate. It’s quite safe to use this generated root certificate, because it’s been specifically generated for your machine and thus is not usable from external sources, the only way to use this certificate in a trusted way is from the local machine. IOW, unless somebody has physical access to your machine, there’s no useful way to hijack this certificate and use it for nefarious purposes (see Eric’s post for more details). Once the Root certificate has been installed, FiddlerCore/Fiddler create new certificates for each site that is connected to with HTTPS. You can end up with quite a few temporary certificates in your certificate store. To uninstall you can either use Fiddler and simply uncheck the Decrypt HTTPS traffic option followed by the remove Fiddler certificates button, or you can use FiddlerCore’s CertMaker.removeFiddlerGeneratedCerts() which removes the root cert and any of the intermediary certificates Fiddler created. Keep in mind that when you uninstall you uninstall the certificate for both FiddlerCore and Fiddler, so use UninstallCertificate() with care and realize that you might affect the Fiddler application’s operation by doing so as well. When to check for an installed Certificate Note that the check to see if the root certificate exists is pretty fast, while the actual process of installing the certificate is a relatively slow operation that even on a fast machine takes a few seconds. Further the trust operation pops up a message box so you probably don’t want to install the certificate repeatedly. Since the check for the root certificate is fast, you can easily put a call to InstallCertificate() in any capture startup code – in which case the certificate installation only triggers when a certificate is in fact not installed. Personally I like to make certificate installation explicit – just like Fiddler does, so in WebSurge I use a small drop down option on the menu to install or uninstall the SSL certificate:   This code calls the InstallCertificate and UnInstallCertificate functions respectively – the experience with this is similar to what you get in Fiddler with the extra dialog box popping up to prompt confirmation for installation of the root certificate. Once the cert is installed you can then capture SSL requests. There’s a gotcha however… Gotcha: FiddlerCore Certificates don’t stick by Default When I originally tried to use the Fiddler certificate installation I ran into an odd problem. I was able to install the certificate and immediately after installation was able to capture HTTPS requests. Then I would exit the application and come back in and try the same HTTPS capture again and it would fail due to a missing certificate. CertMaker.rootCertExists() would return false after every restart and if re-installed the certificate a new certificate would get added to the certificate store resulting in a bunch of duplicated root certificates with different keys. What the heck? CertMaker and BcMakeCert create non-sticky CertificatesI turns out that FiddlerCore by default uses different components from what the full version of Fiddler uses. Fiddler uses a Windows utility called MakeCert.exe to create the Fiddler Root certificate. FiddlerCore however installs the CertMaker.dll and BCMakeCert.dll assemblies, which use a different crypto library (Bouncy Castle) for certificate creation than MakeCert.exe which uses the Windows Crypto API. The assemblies provide support for non-windows operation for Fiddler under Mono, as well as support for some non-Windows certificate platforms like iOS and Android for decryption. The bottom line is that the FiddlerCore provided bouncy castle assemblies are not sticky by default as the certificates created with them are not cached as they are in Fiddler proper. To get certificates to ‘stick’ you have to explicitly cache the certificates in Fiddler’s internal preferences. A cache aware version of InstallCertificate looks something like this:public static bool InstallCertificate() { if (!CertMaker.rootCertExists()) { if (!CertMaker.createRootCert()) return false; if (!CertMaker.trustRootCert()) return false; App.Configuration.UrlCapture.Cert = FiddlerApplication.Prefs.GetStringPref("fiddler.certmaker.bc.cert", null); App.Configuration.UrlCapture.Key = FiddlerApplication.Prefs.GetStringPref("fiddler.certmaker.bc.key", null); } return true; } public static bool UninstallCertificate() { if (CertMaker.rootCertExists()) { if (!CertMaker.removeFiddlerGeneratedCerts(true)) return false; } App.Configuration.UrlCapture.Cert = null; App.Configuration.UrlCapture.Key = null; return true; } In this code I store the Fiddler cert and private key in an application configuration settings that’s stored with the application settings (App.Configuration.UrlCapture object). These settings automatically persist when WebSurge is shut down. The values are read out of Fiddler’s internal preferences store which is set after a new certificate has been created. Likewise I clear out the configuration settings when the certificate is uninstalled. In order for these setting to be used you have to also load the configuration settings into the Fiddler preferences *before* a call to rootCertExists() is made. I do this in the capture form’s constructor:public FiddlerCapture(StressTestForm form) { InitializeComponent(); CaptureConfiguration = App.Configuration.UrlCapture; MainForm = form; if (!string.IsNullOrEmpty(App.Configuration.UrlCapture.Cert)) { FiddlerApplication.Prefs.SetStringPref("fiddler.certmaker.bc.key", App.Configuration.UrlCapture.Key); FiddlerApplication.Prefs.SetStringPref("fiddler.certmaker.bc.cert", App.Configuration.UrlCapture.Cert); }} This is kind of a drag to do and not documented anywhere that I could find, so hopefully this will save you some grief if you want to work with the stock certificate logic that installs with FiddlerCore. MakeCert provides sticky Certificates and the same functionality as Fiddler But there’s actually an easier way. If you want to skip the above Fiddler preference configuration code in your application you can choose to distribute MakeCert.exe instead of certmaker.dll and bcmakecert.dll. When you use MakeCert.exe, the certificates settings are stored in Windows so they are available without any custom configuration inside of your application. It’s easier to integrate and as long as you run on Windows and you don’t need to support iOS or Android devices is simply easier to deal with. To integrate into your project, you can remove the reference to CertMaker.dll (and the BcMakeCert.dll assembly) from your project. Instead copy MakeCert.exe into your output folder. To make sure MakeCert.exe gets pushed out, include MakeCert.exe in your project and set the Build Action to None, and Copy to Output Directory to Copy if newer. Note that the CertMaker.dll reference in the project has been removed and on disk the files for Certmaker.dll, as well as the BCMakeCert.dll files on disk. Keep in mind that these DLLs are resources of the FiddlerCore NuGet package, so updating the package may end up pushing those files back into your project. Once MakeCert.exe is distributed FiddlerCore checks for it first before using the assemblies so as long as MakeCert.exe exists it’ll be used for certificate creation (at least on Windows). Summary FiddlerCore is a pretty sweet tool, and it’s absolutely awesome that we get to plug in most of the functionality of Fiddler right into our own applications. A few years back I tried to build this sort of functionality myself for an app and ended up giving up because it’s a big job to get HTTP right – especially if you need to support SSL. FiddlerCore now provides that functionality as a turnkey solution that can be plugged into your own apps easily. The only downside is FiddlerCore’s documentation for more advanced features like certificate installation which is pretty sketchy. While for the most part FiddlerCore’s feature set is easy to work with without any documentation, advanced features are often not intuitive to gleam by just using Intellisense or the FiddlerCore help file reference (which is not terribly useful). While Eric Lawrence is very responsive on his forum and on Twitter, there simply isn’t much useful documentation on Fiddler/FiddlerCore available online. If you run into trouble the forum is probably the first place to look and then ask a question if you can’t find the answer. The best documentation you can find is Eric’s Fiddler Book which covers a ton of functionality of Fiddler and FiddlerCore. The book is a great reference to Fiddler’s feature set as well as providing great insights into the HTTP protocol. The second half of the book that gets into the innards of HTTP is an excellent read for anybody who wants to know more about some of the more arcane aspects and special behaviors of HTTP – it’s well worth the read. While the book has tons of information in a very readable format, it’s unfortunately not a great reference as it’s hard to find things in the book and because it’s not available online you can’t electronically search for the great content in it. But it’s hard to complain about any of this given the obvious effort and love that’s gone into this awesome product for all of these years. A mighty big thanks to Eric Lawrence  for having created this useful tool that so many of us use all the time, and also to Telerik for picking up Fiddler/FiddlerCore and providing Eric the resources to support and improve this wonderful tool full time and keeping it free for all. Kudos! Resources FiddlerCore Download FiddlerCore NuGet Fiddler Capture Sample Form Fiddler Capture Form in West Wind WebSurge (GitHub) Eric Lawrence’s Fiddler Book© Rick Strahl, West Wind Technologies, 2005-2014Posted in .NET  HTTP   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Eclipse juno can not open with error " An error has occurred. See the log file",ubuntu 12.04

  - by ana

  I'm trying to lunch eclipse for first time ,I've download the package and installed it manually.here is the log file : !SESSION 2012-10-10 16:06:11.460 ----------------------------------------------- eclipse.buildId=M20120914-1800 java.fullversion=GNU libgcj 4.6.3 BootLoader constants: OS=linux, ARCH=x86_64, WS=gtk, NL=en_US Command-line arguments: -os linux -ws gtk -arch x86_64 !ENTRY org.eclipse.osgi 4 0 2012-10-10 16:06:19.756 !MESSAGE Could not start bundle: org.eclipse.equinox.console !STACK 0 org.osgi.framework.BundleException: Could not start bundle: org.eclipse.equinox.console at org.eclipse.osgi.framework.internal.core.ConsoleManager.checkForConsoleBundle(ConsoleManager.java:217) at org.eclipse.core.runtime.adaptor.EclipseStarter.startup(EclipseStarter.java:297) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:176) at java.lang.reflect.Method.invoke(libgcj.so.12) at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584) at org.eclipse.equinox.launcher.Main.run(Main.java:1438) at org.eclipse.equinox.launcher.Main.main(Main.java:1414) Caused by: org.osgi.framework.BundleException: Exception in org.eclipse.equinox.console.command.adapter.Activator.start() of bundle org.eclipse.equinox.console. at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:734) at org.eclipse.osgi.framework.internal.core.BundleContextImpl.start(BundleContextImpl.java:683) at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:381) at org.eclipse.osgi.framework.internal.core.AbstractBundle.start(AbstractBundle.java:300) at org.eclipse.osgi.framework.internal.core.ConsoleManager.checkForConsoleBundle(ConsoleManager.java:215) ...7 more Caused by: org.osgi.framework.BundleException: Exception in org.apache.felix.gogo.command.Activator.start() of bundle org.apache.felix.gogo.command. at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:734) at org.eclipse.osgi.framework.internal.core.BundleContextImpl.start(BundleContextImpl.java:683) at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:381) at org.eclipse.osgi.framework.internal.core.AbstractBundle.start(AbstractBundle.java:300) at org.eclipse.equinox.console.command.adapter.Activator.startBundle(Activator.java:248) at org.eclipse.equinox.console.command.adapter.Activator.start(Activator.java:239) at org.eclipse.osgi.framework.internal.core.BundleContextImpl$1.run(BundleContextImpl.java:711) at java.security.AccessController.doPrivileged(libgcj.so.12) at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:702) ...11 more Caused by: java.lang.NoClassDefFoundError: org.apache.felix.gogo.command.OBR at java.lang.Class.initializeClass(libgcj.so.12) at org.apache.felix.gogo.command.Activator.start(Activator.java:54) at org.eclipse.osgi.framework.internal.core.BundleContextImpl$1.run(BundleContextImpl.java:711) at java.security.AccessController.doPrivileged(libgcj.so.12) at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:702) ...19 more Caused by: java.lang.ClassNotFoundException: org.apache.felix.bundlerepository.Repository at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:501) at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421) at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412) at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107) at java.lang.ClassLoader.loadClass(libgcj.so.12) at java.lang.Class.initializeClass(libgcj.so.12) ...23 more Root exception: java.lang.NoClassDefFoundError: org.apache.felix.gogo.command.OBR at java.lang.Class.initializeClass(libgcj.so.12) at !ENTRY org.eclipse.osgi 2 0 2012-10-10 16:06:30.433 !MESSAGE The following is a complete list of bundles which are not resolved, see the prior log entry for the root cause if it exists: !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.433 !MESSAGE Bundle com.sun.el_2.2.0.v201108011116 [4] was not resolved. !SUBENTRY 2 com.sun.el 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.el_2.2.0. !SUBENTRY 2 com.sun.el 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet.http_2.5.0. !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.434 !MESSAGE Bundle javax.el_2.2.0.v201108011116 [6] was not resolved. !SUBENTRY 2 javax.el 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet_2.5.0. !SUBENTRY 2 javax.el 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet.http_2.5.0. !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.434 !MESSAGE Bundle javax.servlet_3.0.0.v201112011016 [8] was not resolved. !SUBENTRY 2 javax.servlet 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(&(osgi.ee=JavaSE)(version=1.6))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.434 !MESSAGE Bundle javax.servlet.jsp_2.2.0.v201112011158 [9] was not resolved. !SUBENTRY 2 javax.servlet.jsp 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.el_2.2.0. !SUBENTRY 2 javax.servlet.jsp 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet_2.6.0. !SUBENTRY 2 javax.servlet.jsp 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet.http_2.6.0. !SUBENTRY 2 javax.servlet.jsp 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(&(osgi.ee=JavaSE)(version=1.6))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.434 !MESSAGE Bundle org.apache.jasper.glassfish_2.2.2.v201205150955 [21] was not resolved. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.el_2.2.0. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet_2.6.0. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet.descriptor_2.6.0. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet.http_2.6.0. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet.jsp_2.2.0. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet.jsp.el_2.2.0. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet.jsp.tagext_2.2.0. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing optionally imported package javax.tools_0.0.0. !SUBENTRY 2 org.apache.jasper.glassfish 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(&(osgi.ee=JavaSE)(version=1.6))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.434 !MESSAGE Bundle org.eclipse.equinox.http.jetty_3.0.0.v20120522-1841 [91] was not resolved. !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.434 !MESSAGE Missing imported package javax.servlet_[2.6.0,4.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package javax.servlet.http_[2.6.0,4.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.equinox.http.servlet_1.0.0. !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.http_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.io.bio_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.io.nio_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.server_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.server.bio_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.server.handler_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.server.nio_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.server.session_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.server.ssl_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.servlet_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.util_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.util.component_[8.0.0,9.0.0). !SUBENTRY 2 org.eclipse.equinox.http.jetty 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package org.eclipse.jetty.util.log_[8.0.0,9.0.0). !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.435 !MESSAGE Bundle org.eclipse.equinox.http.registry_1.1.200.v20120522-2049 [92] was not resolved. !SUBENTRY 2 org.eclipse.equinox.http.registry 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package javax.servlet_2.3.0. !SUBENTRY 2 org.eclipse.equinox.http.registry 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package javax.servlet.http_2.3.0. !SUBENTRY 2 org.eclipse.equinox.http.registry 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(|(&(osgi.ee=CDC/Foundation)(version=1.0))(&(osgi.ee=JavaSE)(version=1.3)))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.435 !MESSAGE Bundle org.eclipse.equinox.http.servlet_1.1.300.v20120522-1841 [93] was not resolved. !SUBENTRY 2 org.eclipse.equinox.http.servlet 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package javax.servlet_[2.3.0,3.1.0). !SUBENTRY 2 org.eclipse.equinox.http.servlet 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing optionally imported package javax.servlet.annotation_2.6.0. !SUBENTRY 2 org.eclipse.equinox.http.servlet 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing optionally imported package javax.servlet.descriptor_2.6.0. !SUBENTRY 2 org.eclipse.equinox.http.servlet 2 0 2012-10-10 16:06:30.435 !MESSAGE Missing imported package javax.servlet.http_[2.3.0,3.1.0). !SUBENTRY 2 org.eclipse.equinox.http.servlet 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(|(&(osgi.ee=CDC/Foundation)(version=1.0))(&(osgi.ee=JavaSE)(version=1.3)))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.436 !MESSAGE Bundle org.eclipse.equinox.jsp.jasper_1.0.400.v20120522-2049 [94] was not resolved. !SUBENTRY 2 org.eclipse.equinox.jsp.jasper 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package javax.servlet_[2.4.0,3.1.0). !SUBENTRY 2 org.eclipse.equinox.jsp.jasper 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing optionally imported package javax.servlet.annotation_2.6.0. !SUBENTRY 2 org.eclipse.equinox.jsp.jasper 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing optionally imported package javax.servlet.descriptor_2.6.0. !SUBENTRY 2 org.eclipse.equinox.jsp.jasper 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package javax.servlet.http_[2.4.0,3.1.0). !SUBENTRY 2 org.eclipse.equinox.jsp.jasper 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package javax.servlet.jsp_[2.0.0,2.3.0). !SUBENTRY 2 org.eclipse.equinox.jsp.jasper 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package org.apache.jasper.servlet_[0.0.0,6.0.0). !SUBENTRY 2 org.eclipse.equinox.jsp.jasper 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(|(&(osgi.ee=CDC/Foundation)(version=1.0))(&(osgi.ee=JavaSE)(version=1.3)))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.436 !MESSAGE Bundle org.eclipse.equinox.jsp.jasper.registry_1.0.300.v20120522-2049 [95] was not resolved. !SUBENTRY 2 org.eclipse.equinox.jsp.jasper.registry 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package org.eclipse.equinox.jsp.jasper_0.0.0. !SUBENTRY 2 org.eclipse.equinox.jsp.jasper.registry 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package javax.servlet_2.4.0. !SUBENTRY 2 org.eclipse.equinox.jsp.jasper.registry 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package javax.servlet.http_2.4.0. !SUBENTRY 2 org.eclipse.equinox.jsp.jasper.registry 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(|(&(osgi.ee=CDC/Foundation)(version=1.0))(&(osgi.ee=JavaSE)(version=1.3)))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.436 !MESSAGE Bundle org.eclipse.help.webapp_3.6.101.v20120717-130216 [135] was not resolved. !SUBENTRY 2 org.eclipse.help.webapp 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing required bundle org.eclipse.equinox.jsp.jasper.registry_1.0.100. !SUBENTRY 2 org.eclipse.help.webapp 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing required bundle org.eclipse.equinox.http.registry_1.0.200. !SUBENTRY 2 org.eclipse.help.webapp 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package javax.servlet_2.4.0. !SUBENTRY 2 org.eclipse.help.webapp 2 0 2012-10-10 16:06:30.436 !MESSAGE Missing imported package javax.servlet.http_2.4.0. !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.437 !MESSAGE Bundle org.eclipse.jdt.apt.pluggable.core_1.0.400.v20120522-1651 [139] was not resolved. !SUBENTRY 2 org.eclipse.jdt.apt.pluggable.core 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing imported package org.eclipse.jdt.internal.compiler.tool_0.0.0. !SUBENTRY 2 org.eclipse.jdt.apt.pluggable.core 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing imported package org.eclipse.jdt.internal.compiler.apt.dispatch_0.0.0. !SUBENTRY 2 org.eclipse.jdt.apt.pluggable.core 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing imported package org.eclipse.jdt.internal.compiler.apt.model_0.0.0. !SUBENTRY 2 org.eclipse.jdt.apt.pluggable.core 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing imported package org.eclipse.jdt.internal.compiler.apt.util_0.0.0. !SUBENTRY 2 org.eclipse.jdt.apt.pluggable.core 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(&(osgi.ee=JavaSE)(version=1.6))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.437 !MESSAGE Bundle org.eclipse.jdt.compiler.apt_1.0.500.v20120522-1651 [141] was not resolved. !SUBENTRY 2 org.eclipse.jdt.compiler.apt 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing optionally imported package org.eclipse.jdt.internal.compiler.tool_0.0.0. !SUBENTRY 2 org.eclipse.jdt.compiler.apt 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(&(osgi.ee=JavaSE)(version=1.6))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.437 !MESSAGE Bundle org.eclipse.jdt.compiler.tool_1.0.101.v20120522-1651 [142] was not resolved. !SUBENTRY 2 org.eclipse.jdt.compiler.tool 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(&(osgi.ee=JavaSE)(version=1.6))". !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.437 !MESSAGE Bundle org.eclipse.jetty.continuation_8.1.3.v20120522 [155] was not resolved. !SUBENTRY 2 org.eclipse.jetty.continuation 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing imported package javax.servlet_2.6.0. !SUBENTRY 2 org.eclipse.jetty.continuation 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing optionally imported package org.mortbay.log_[6.1.0,7.0.0). !SUBENTRY 2 org.eclipse.jetty.continuation 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing optionally imported package org.mortbay.util.ajax_[6.1.0,7.0.0). !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.437 !MESSAGE Bundle org.eclipse.jetty.http_8.1.3.v20120522 [156] was not resolved. !SUBENTRY 2 org.eclipse.jetty.http 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing imported package javax.servlet_2.6.0. !SUBENTRY 2 org.eclipse.jetty.http 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing imported package javax.servlet.http_2.6.0. !SUBENTRY 2 org.eclipse.jetty.http 2 0 2012-10-10 16:06:30.437 !MESSAGE Missing imported package org.eclipse.jetty.io_[8.1.0,9.0.0). org.eclipse.jetty.util.resource_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.http 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package org.eclipse.jetty.util.ssl_[8.1.0,9.0.0). !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.438 !MESSAGE Bundle org.eclipse.jetty.io_8.1.3.v20120522 [157] was not resolved. !SUBENTRY 2 org.eclipse.jetty.io 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package org.eclipse.jetty.util_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.io 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package org.eclipse.jetty.util.component_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.io 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package org.eclipse.jetty.util.log_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.io 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package org.eclipse.jetty.util.thread_[8.1.0,9.0.0). !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.438 !MESSAGE Bundle org.eclipse.jetty.security_8.1.3.v20120522 [158] was not resolved. !SUBENTRY 2 org.eclipse.jetty.security 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package javax.servlet_2.6.0. !SUBENTRY 2 org.eclipse.jetty.security 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package javax.servlet.http_2.6.0. !SUBENTRY 2 org.eclipse.jetty.security 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package org.eclipse.jetty.http_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.security 2 0 2012-10-10 16:06:30.438 !MESSAGE Missing imported package org.eclipse.jetty.server_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.security 2 0 2012-10-10 16:06:30.438 org.eclipse.jetty.jmx_8.0.0. !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.439 !MESSAGE Missing imported package org.eclipse.jetty.security_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing imported package org.eclipse.jetty.server_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing imported package org.eclipse.jetty.server.handler_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing imported package org.eclipse.jetty.server.nio_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing imported package org.eclipse.jetty.server.session_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing imported package org.eclipse.jetty.server.ssl_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing optionally imported package org.eclipse.jetty.util_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing optionally imported package org.eclipse.jetty.util.component_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing optionally imported package org.eclipse.jetty.util.log_[8.1.0,9.0.0). !SUBENTRY 2 org.eclipse.jetty.servlet 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing optionally imported package org.eclipse.jetty.util.resource_[8.1.0,9.0.0). !SUBENTRY 1 org.eclipse.osgi 2 0 2012-10-10 16:06:30.440 !MESSAGE Bundle org.eclipse.jetty.util_8.1.3.v20120522 [161] was not resolved. !SUBENTRY 2 org.eclipse.jetty.util 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing imported package javax.servlet_2.6.0. !SUBENTRY 2 org.eclipse.jetty.util 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing imported package javax.servlet.http_2.6.0. !SUBENTRY 2 org.eclipse.jetty.util 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing optionally imported package org.slf4j_[1.5.0,2.0.0). !SUBENTRY 2 org.eclipse.jetty.util 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing optionally imported package org.slf4j.helpers_[1.6.0,2.0.0). !SUBENTRY 2 org.eclipse.jetty.util 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing optionally imported package org.slf4j.impl_[1.5.0,2.0.0). !SUBENTRY 2 org.eclipse.jetty.util 2 0 2012-10-10 16:06:30.440 !MESSAGE Missing optionally imported package org.slf4j.spi_[1.6.0,2.0.0). !ENTRY org.eclipse.osgi 4 0 2012-10-10 16:06:30.441 !MESSAGE Application error !STACK 1 java.lang.ArrayIndexOutOfBoundsException: 0 at org.eclipse.e4.core.internal.di.ConstructorRequestor.calcDependentObjects(ConstructorRequestor.java:79) at org.eclipse.e4.core.internal.di.Requestor.getDependentObjects(Requestor.java:143) at org.eclipse.e4.core.internal.di.InjectorImpl.resolveArgs(InjectorImpl.java:408) at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:312) at org.eclipse.e4.core.internal.di.InjectorImpl.make(InjectorImpl.java:240) at org.eclipse.e4.core.contexts.ContextInjectionFactory.make(ContextInjectionFactory.java:161) at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createDefaultHeadlessContext(E4Application.java:420) at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createDefaultContext(E4Application.java:434) at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createE4Workbench(E4Application.java:182) at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:557) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:543) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149) at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:124) at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180) at java.lang.reflect.Method.invoke(libgcj.so.12) at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584) at org.eclipse.equinox.launcher.Main.run(Main.java:1438) at org.eclipse.equinox.launcher.Main.main(Main.java:1414) would you please help me with this?

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• Creating Custom Ajax Control Toolkit Controls

  - by Stephen Walther

  The goal of this blog entry is to explain how you can extend the Ajax Control Toolkit with custom Ajax Control Toolkit controls. I describe how you can create the two halves of an Ajax Control Toolkit control: the server-side control extender and the client-side control behavior. Finally, I explain how you can use the new Ajax Control Toolkit control in a Web Forms page. At the end of this blog entry, there is a link to download a Visual Studio 2010 solution which contains the code for two Ajax Control Toolkit controls: SampleExtender and PopupHelpExtender. The SampleExtender contains the minimum skeleton for creating a new Ajax Control Toolkit control. You can use the SampleExtender as a starting point for your custom Ajax Control Toolkit controls. The PopupHelpExtender control is a super simple custom Ajax Control Toolkit control. This control extender displays a help message when you start typing into a TextBox control. The animated GIF below demonstrates what happens when you click into a TextBox which has been extended with the PopupHelp extender. Here’s a sample of a Web Forms page which uses the control: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ShowPopupHelp.aspx.cs" Inherits="MyACTControls.Web.Default" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html > <head runat="server"> <title>Show Popup Help</title> </head> <body> <form id="form1" runat="server"> <div> <act:ToolkitScriptManager ID="tsm" runat="server" /> <%-- Social Security Number --%> <asp:Label ID="lblSSN" Text="SSN:" AssociatedControlID="txtSSN" runat="server" /> <asp:TextBox ID="txtSSN" runat="server" /> <act:PopupHelpExtender id="ph1" TargetControlID="txtSSN" HelpText="Please enter your social security number." runat="server" /> <%-- Social Security Number --%> <asp:Label ID="lblPhone" Text="Phone Number:" AssociatedControlID="txtPhone" runat="server" /> <asp:TextBox ID="txtPhone" runat="server" /> <act:PopupHelpExtender id="ph2" TargetControlID="txtPhone" HelpText="Please enter your phone number." runat="server" /> </div> </form> </body> </html> In the page above, the PopupHelp extender is used to extend the functionality of the two TextBox controls. When focus is given to a TextBox control, the popup help message is displayed. An Ajax Control Toolkit control extender consists of two parts: a server-side control extender and a client-side behavior. For example, the PopupHelp extender consists of a server-side PopupHelpExtender control (PopupHelpExtender.cs) and a client-side PopupHelp behavior JavaScript script (PopupHelpBehavior.js). Over the course of this blog entry, I describe how you can create both the server-side extender and the client-side behavior. Writing the Server-Side Code Creating a Control Extender You create a control extender by creating a class that inherits from the abstract ExtenderControlBase class. For example, the PopupHelpExtender control is declared like this: public class PopupHelpExtender: ExtenderControlBase { } The ExtenderControlBase class is part of the Ajax Control Toolkit. This base class contains all of the common server properties and methods of every Ajax Control Toolkit extender control. The ExtenderControlBase class inherits from the ExtenderControl class. The ExtenderControl class is a standard class in the ASP.NET framework located in the System.Web.UI namespace. This class is responsible for generating a client-side behavior. The class generates a call to the Microsoft Ajax Library $create() method which looks like this: <script type="text/javascript"> $create(MyACTControls.PopupHelpBehavior, {"HelpText":"Please enter your social security number.","id":"ph1"}, null, null, $get("txtSSN")); }); </script> The JavaScript $create() method is part of the Microsoft Ajax Library. The reference for this method can be found here: http://msdn.microsoft.com/en-us/library/bb397487.aspx This method accepts the following parameters: type – The type of client behavior to create. The $create() method above creates a client PopupHelpBehavior. Properties – Enables you to pass initial values for the properties of the client behavior. For example, the initial value of the HelpText property. This is how server property values are passed to the client. Events – Enables you to pass client-side event handlers to the client behavior. References – Enables you to pass references to other client components. Element – The DOM element associated with the client behavior. This will be the DOM element associated with the control being extended such as the txtSSN TextBox. The $create() method is generated for you automatically. You just need to focus on writing the server-side control extender class. Specifying the Target Control All Ajax Control Toolkit extenders inherit a TargetControlID property from the ExtenderControlBase class. This property, the TargetControlID property, points at the control that the extender control extends. For example, the Ajax Control Toolkit TextBoxWatermark control extends a TextBox, the ConfirmButton control extends a Button, and the Calendar control extends a TextBox. You must indicate the type of control which your extender is extending. You indicate the type of control by adding a [TargetControlType] attribute to your control. For example, the PopupHelp extender is declared like this: [TargetControlType(typeof(TextBox))] public class PopupHelpExtender: ExtenderControlBase { } The PopupHelp extender can be used to extend a TextBox control. If you try to use the PopupHelp extender with another type of control then an exception is thrown. If you want to create an extender control which can be used with any type of ASP.NET control (Button, DataView, TextBox or whatever) then use the following attribute: [TargetControlType(typeof(Control))] Decorating Properties with Attributes If you decorate a server-side property with the [ExtenderControlProperty] attribute then the value of the property gets passed to the control’s client-side behavior. The value of the property gets passed to the client through the $create() method discussed above. The PopupHelp control contains the following HelpText property: [ExtenderControlProperty] [RequiredProperty] public string HelpText { get { return GetPropertyValue("HelpText", "Help Text"); } set { SetPropertyValue("HelpText", value); } } The HelpText property determines the help text which pops up when you start typing into a TextBox control. Because the HelpText property is decorated with the [ExtenderControlProperty] attribute, any value assigned to this property on the server is passed to the client automatically. For example, if you declare the PopupHelp extender in a Web Form page like this: <asp:TextBox ID="txtSSN" runat="server" /> <act:PopupHelpExtender id="ph1" TargetControlID="txtSSN" HelpText="Please enter your social security number." runat="server" />   Then the PopupHelpExtender renders the call to the the following Microsoft Ajax Library $create() method: $create(MyACTControls.PopupHelpBehavior, {"HelpText":"Please enter your social security number.","id":"ph1"}, null, null, $get("txtSSN")); You can see this call to the JavaScript $create() method by selecting View Source in your browser. This call to the $create() method calls a method named set_HelpText() automatically and passes the value “Please enter your social security number”. There are several attributes which you can use to decorate server-side properties including: ExtenderControlProperty – When a property is marked with this attribute, the value of the property is passed to the client automatically. ExtenderControlEvent – When a property is marked with this attribute, the property represents a client event handler. Required – When a value is not assigned to this property on the server, an error is displayed. DefaultValue – The default value of the property passed to the client. ClientPropertyName – The name of the corresponding property in the JavaScript behavior. For example, the server-side property is named ID (uppercase) and the client-side property is named id (lower-case). IDReferenceProperty – Applied to properties which refer to the IDs of other controls. URLProperty – Calls ResolveClientURL() to convert from a server-side URL to a URL which can be used on the client. ElementReference – Returns a reference to a DOM element by performing a client $get(). The WebResource, ClientResource, and the RequiredScript Attributes The PopupHelp extender uses three embedded resources named PopupHelpBehavior.js, PopupHelpBehavior.debug.js, and PopupHelpBehavior.css. The first two files are JavaScript files and the final file is a Cascading Style sheet file. These files are compiled as embedded resources. You don’t need to mark them as embedded resources in your Visual Studio solution because they get added to the assembly when the assembly is compiled by a build task. You can see that these files get embedded into the MyACTControls assembly by using Red Gate’s .NET Reflector tool: In order to use these files with the PopupHelp extender, you need to work with both the WebResource and the ClientScriptResource attributes. The PopupHelp extender includes the following three WebResource attributes. [assembly: WebResource("PopupHelp.PopupHelpBehavior.js", "text/javascript")] [assembly: WebResource("PopupHelp.PopupHelpBehavior.debug.js", "text/javascript")] [assembly: WebResource("PopupHelp.PopupHelpBehavior.css", "text/css", PerformSubstitution = true)] These WebResource attributes expose the embedded resource from the assembly so that they can be accessed by using the ScriptResource.axd or WebResource.axd handlers. The first parameter passed to the WebResource attribute is the name of the embedded resource and the second parameter is the content type of the embedded resource. The PopupHelp extender also includes the following ClientScriptResource and ClientCssResource attributes: [ClientScriptResource("MyACTControls.PopupHelpBehavior", "PopupHelp.PopupHelpBehavior.js")] [ClientCssResource("PopupHelp.PopupHelpBehavior.css")] Including these attributes causes the PopupHelp extender to request these resources when you add the PopupHelp extender to a page. If you open View Source in a browser which uses the PopupHelp extender then you will see the following link for the Cascading Style Sheet file: <link href="/WebResource.axd?d=0uONMsWXUuEDG-pbJHAC1kuKiIMteQFkYLmZdkgv7X54TObqYoqVzU4mxvaa4zpn5H9ch0RDwRYKwtO8zM5mKgO6C4WbrbkWWidKR07LD1d4n4i_uNB1mHEvXdZu2Ae5mDdVNDV53znnBojzCzwvSw2&amp;t=634417392021676003" type="text/css" rel="stylesheet" /> You also will see the following script include for the JavaScript file: <script src="/ScriptResource.axd?d=pIS7xcGaqvNLFBvExMBQSp_0xR3mpDfS0QVmmyu1aqDUjF06TrW1jVDyXNDMtBHxpRggLYDvgFTWOsrszflZEDqAcQCg-hDXjun7ON0Ol7EXPQIdOe1GLMceIDv3OeX658-tTq2LGdwXhC1-dE7_6g2&amp;t=ffffffff88a33b59" type="text/javascript"></script> The JavaScrpt file returned by this request to ScriptResource.axd contains the combined scripts for any and all Ajax Control Toolkit controls in a page. By default, the Ajax Control Toolkit combines all of the JavaScript files required by a page into a single JavaScript file. Combining files in this way really speeds up how quickly all of the JavaScript files get delivered from the web server to the browser. So, by default, there will be only one ScriptResource.axd include for all of the JavaScript files required by a page. If you want to disable Script Combining, and create separate links, then disable Script Combining like this: <act:ToolkitScriptManager ID="tsm" runat="server" CombineScripts="false" /> There is one more important attribute used by Ajax Control Toolkit extenders. The PopupHelp behavior uses the following two RequirdScript attributes to load the JavaScript files which are required by the PopupHelp behavior: [RequiredScript(typeof(CommonToolkitScripts), 0)] [RequiredScript(typeof(PopupExtender), 1)] The first parameter of the RequiredScript attribute represents either the string name of a JavaScript file or the type of an Ajax Control Toolkit control. The second parameter represents the order in which the JavaScript files are loaded (This second parameter is needed because .NET attributes are intrinsically unordered). In this case, the RequiredScript attribute will load the JavaScript files associated with the CommonToolkitScripts type and the JavaScript files associated with the PopupExtender in that order. The PopupHelp behavior depends on these JavaScript files. Writing the Client-Side Code The PopupHelp extender uses a client-side behavior written with the Microsoft Ajax Library. Here is the complete code for the client-side behavior: (function () { // The unique name of the script registered with the // client script loader var scriptName = "PopupHelpBehavior"; function execute() { Type.registerNamespace('MyACTControls'); MyACTControls.PopupHelpBehavior = function (element) { /// <summary> /// A behavior which displays popup help for a textbox /// </summmary> /// <param name="element" type="Sys.UI.DomElement">The element to attach to</param> MyACTControls.PopupHelpBehavior.initializeBase(this, [element]); this._textbox = Sys.Extended.UI.TextBoxWrapper.get_Wrapper(element); this._cssClass = "ajax__popupHelp"; this._popupBehavior = null; this._popupPosition = Sys.Extended.UI.PositioningMode.BottomLeft; this._popupDiv = null; this._helpText = "Help Text"; this._element$delegates = { focus: Function.createDelegate(this, this._element_onfocus), blur: Function.createDelegate(this, this._element_onblur) }; } MyACTControls.PopupHelpBehavior.prototype = { initialize: function () { MyACTControls.PopupHelpBehavior.callBaseMethod(this, 'initialize'); // Add event handlers for focus and blur var element = this.get_element(); $addHandlers(element, this._element$delegates); }, _ensurePopup: function () { if (!this._popupDiv) { var element = this.get_element(); var id = this.get_id(); this._popupDiv = $common.createElementFromTemplate({ nodeName: "div", properties: { id: id + "_popupDiv" }, cssClasses: ["ajax__popupHelp"] }, element.parentNode); this._popupBehavior = new $create(Sys.Extended.UI.PopupBehavior, { parentElement: element }, {}, {}, this._popupDiv); this._popupBehavior.set_positioningMode(this._popupPosition); } }, get_HelpText: function () { return this._helpText; }, set_HelpText: function (value) { if (this._HelpText != value) { this._helpText = value; this._ensurePopup(); this._popupDiv.innerHTML = value; this.raisePropertyChanged("Text") } }, _element_onfocus: function (e) { this.show(); }, _element_onblur: function (e) { this.hide(); }, show: function () { this._popupBehavior.show(); }, hide: function () { if (this._popupBehavior) { this._popupBehavior.hide(); } }, dispose: function() { var element = this.get_element(); $clearHandlers(element); if (this._popupBehavior) { this._popupBehavior.dispose(); this._popupBehavior = null; } } }; MyACTControls.PopupHelpBehavior.registerClass('MyACTControls.PopupHelpBehavior', Sys.Extended.UI.BehaviorBase); Sys.registerComponent(MyACTControls.PopupHelpBehavior, { name: "popupHelp" }); } // execute if (window.Sys && Sys.loader) { Sys.loader.registerScript(scriptName, ["ExtendedBase", "ExtendedCommon"], execute); } else { execute(); } })();   In the following sections, we’ll discuss how this client-side behavior works. Wrapping the Behavior for the Script Loader The behavior is wrapped with the following script: (function () { // The unique name of the script registered with the // client script loader var scriptName = "PopupHelpBehavior"; function execute() { // Behavior Content } // execute if (window.Sys && Sys.loader) { Sys.loader.registerScript(scriptName, ["ExtendedBase", "ExtendedCommon"], execute); } else { execute(); } })(); This code is required by the Microsoft Ajax Library Script Loader. You need this code if you plan to use a behavior directly from client-side code and you want to use the Script Loader. If you plan to only use your code in the context of the Ajax Control Toolkit then you can leave out this code. Registering a JavaScript Namespace The PopupHelp behavior is declared within a namespace named MyACTControls. In the code above, this namespace is created with the following registerNamespace() method: Type.registerNamespace('MyACTControls'); JavaScript does not have any built-in way of creating namespaces to prevent naming conflicts. The Microsoft Ajax Library extends JavaScript with support for namespaces. You can learn more about the registerNamespace() method here: http://msdn.microsoft.com/en-us/library/bb397723.aspx Creating the Behavior The actual Popup behavior is created with the following code. MyACTControls.PopupHelpBehavior = function (element) { /// <summary> /// A behavior which displays popup help for a textbox /// </summmary> /// <param name="element" type="Sys.UI.DomElement">The element to attach to</param> MyACTControls.PopupHelpBehavior.initializeBase(this, [element]); this._textbox = Sys.Extended.UI.TextBoxWrapper.get_Wrapper(element); this._cssClass = "ajax__popupHelp"; this._popupBehavior = null; this._popupPosition = Sys.Extended.UI.PositioningMode.BottomLeft; this._popupDiv = null; this._helpText = "Help Text"; this._element$delegates = { focus: Function.createDelegate(this, this._element_onfocus), blur: Function.createDelegate(this, this._element_onblur) }; } MyACTControls.PopupHelpBehavior.prototype = { initialize: function () { MyACTControls.PopupHelpBehavior.callBaseMethod(this, 'initialize'); // Add event handlers for focus and blur var element = this.get_element(); $addHandlers(element, this._element$delegates); }, _ensurePopup: function () { if (!this._popupDiv) { var element = this.get_element(); var id = this.get_id(); this._popupDiv = $common.createElementFromTemplate({ nodeName: "div", properties: { id: id + "_popupDiv" }, cssClasses: ["ajax__popupHelp"] }, element.parentNode); this._popupBehavior = new $create(Sys.Extended.UI.PopupBehavior, { parentElement: element }, {}, {}, this._popupDiv); this._popupBehavior.set_positioningMode(this._popupPosition); } }, get_HelpText: function () { return this._helpText; }, set_HelpText: function (value) { if (this._HelpText != value) { this._helpText = value; this._ensurePopup(); this._popupDiv.innerHTML = value; this.raisePropertyChanged("Text") } }, _element_onfocus: function (e) { this.show(); }, _element_onblur: function (e) { this.hide(); }, show: function () { this._popupBehavior.show(); }, hide: function () { if (this._popupBehavior) { this._popupBehavior.hide(); } }, dispose: function() { var element = this.get_element(); $clearHandlers(element); if (this._popupBehavior) { this._popupBehavior.dispose(); this._popupBehavior = null; } } }; The code above has two parts. The first part of the code is used to define the constructor function for the PopupHelp behavior. This is a factory method which returns an instance of a PopupHelp behavior: MyACTControls.PopupHelpBehavior = function (element) { } The second part of the code modified the prototype for the PopupHelp behavior: MyACTControls.PopupHelpBehavior.prototype = { } Any code which is particular to a single instance of the PopupHelp behavior should be placed in the constructor function. For example, the default value of the _helpText field is assigned in the constructor function: this._helpText = "Help Text"; Any code which is shared among all instances of the PopupHelp behavior should be added to the PopupHelp behavior’s prototype. For example, the public HelpText property is added to the prototype: get_HelpText: function () { return this._helpText; }, set_HelpText: function (value) { if (this._HelpText != value) { this._helpText = value; this._ensurePopup(); this._popupDiv.innerHTML = value; this.raisePropertyChanged("Text") } }, Registering a JavaScript Class After you create the PopupHelp behavior, you must register the behavior as a class by using the Microsoft Ajax registerClass() method like this: MyACTControls.PopupHelpBehavior.registerClass('MyACTControls.PopupHelpBehavior', Sys.Extended.UI.BehaviorBase); This call to registerClass() registers PopupHelp behavior as a class which derives from the base Sys.Extended.UI.BehaviorBase class. Like the ExtenderControlBase class on the server side, the BehaviorBase class on the client side contains method used by every behavior. The documentation for the BehaviorBase class can be found here: http://msdn.microsoft.com/en-us/library/bb311020.aspx The most important methods and properties of the BehaviorBase class are the following: dispose() – Use this method to clean up all resources used by your behavior. In the case of the PopupHelp behavior, the dispose() method is used to remote the event handlers created by the behavior and disposed the Popup behavior. get_element() -- Use this property to get the DOM element associated with the behavior. In other words, the DOM element which the behavior extends. get_id() – Use this property to the ID of the current behavior. initialize() – Use this method to initialize the behavior. This method is called after all of the properties are set by the $create() method. Creating Debug and Release Scripts You might have noticed that the PopupHelp behavior uses two scripts named PopupHelpBehavior.js and PopupHelpBehavior.debug.js. However, you never create these two scripts. Instead, you only create a single script named PopupHelpBehavior.pre.js. The pre in PopupHelpBehavior.pre.js stands for preprocessor. When you build the Ajax Control Toolkit (or the sample Visual Studio Solution at the end of this blog entry), a build task named JSBuild generates the PopupHelpBehavior.js release script and PopupHelpBehavior.debug.js debug script automatically. The JSBuild preprocessor supports the following directives: #IF #ELSE #ENDIF #INCLUDE #LOCALIZE #DEFINE #UNDEFINE The preprocessor directives are used to mark code which should only appear in the debug version of the script. The directives are used extensively in the Microsoft Ajax Library. For example, the Microsoft Ajax Library Array.contains() method is created like this: $type.contains = function Array$contains(array, item) { //#if DEBUG var e = Function._validateParams(arguments, [ {name: "array", type: Array, elementMayBeNull: true}, {name: "item", mayBeNull: true} ]); if (e) throw e; //#endif return (indexOf(array, item) >= 0); } Notice that you add each of the preprocessor directives inside a JavaScript comment. The comment prevents Visual Studio from getting confused with its Intellisense. The release version, but not the debug version, of the PopupHelpBehavior script is also minified automatically by the Microsoft Ajax Minifier. The minifier is invoked by a build step in the project file. Conclusion The goal of this blog entry was to explain how you can create custom AJAX Control Toolkit controls. In the first part of this blog entry, you learned how to create the server-side portion of an Ajax Control Toolkit control. You learned how to derive a new control from the ExtenderControlBase class and decorate its properties with the necessary attributes. Next, in the second part of this blog entry, you learned how to create the client-side portion of an Ajax Control Toolkit control by creating a client-side behavior with JavaScript. You learned how to use the methods of the Microsoft Ajax Library to extend your client behavior from the BehaviorBase class. Download the Custom ACT Starter Solution

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• Oracle Coherence, Split-Brain and Recovery Protocols In Detail

  - by Ricardo Ferreira

  This article provides a high level conceptual overview of Split-Brain scenarios in distributed systems. It will focus on a specific example of cluster communication failure and recovery in Oracle Coherence. This includes a discussion on the witness protocol (used to remove failed cluster members) and the panic protocol (used to resolve Split-Brain scenarios). Note that the removal of cluster members does not necessarily indicate a Split-Brain condition. Oracle Coherence does not (and cannot) detect a Split-Brain as it occurs, the condition is only detected when cluster members that previously lost contact with each other regain contact. Cluster Topology and Configuration In order to create an good didactic for the article, let's assume a cluster topology and configuration. In this example we have a six member cluster, consisting of one JVM on each physical machine. The member IDs are as follows: Member ID  IP Address  1  10.149.155.76  2  10.149.155.77  3  10.149.155.236  4  10.149.155.75  5  10.149.155.79  6  10.149.155.78 Members 1, 2, and 3 are connected to a switch, and members 4, 5, and 6 are connected to a second switch. There is a link between the two switches, which provides network connectivity between all of the machines. Member 1 is the first member to join this cluster, thus making it the senior member. Member 6 is the last member to join this cluster. Here is a log snippet from Member 6 showing the complete member set: 2010-02-26 15:27:57.390/3.062 Oracle Coherence GE 3.5.3/465p2 <Info> (thread=main, member=6): Started DefaultCacheServer... SafeCluster: Name=cluster:0xDDEB Group{Address=224.3.5.3, Port=35465, TTL=4} MasterMemberSet ( ThisMember=Member(Id=6, Timestamp=2010-02-26 15:27:58.635, Address=10.149.155.78:8088, MachineId=1102, Location=process:228, Role=CoherenceServer) OldestMember=Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) ActualMemberSet=MemberSet(Size=6, BitSetCount=2 Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) Member(Id=2, Timestamp=2010-02-26 15:27:17.847, Address=10.149.155.77:8088, MachineId=1101, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:296, Role=CoherenceServer) Member(Id=3, Timestamp=2010-02-26 15:27:24.892, Address=10.149.155.236:8088, MachineId=1260, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:32459, Role=CoherenceServer) Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) Member(Id=5, Timestamp=2010-02-26 15:27:49.095, Address=10.149.155.79:8088, MachineId=1103, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:3229, Role=CoherenceServer) Member(Id=6, Timestamp=2010-02-26 15:27:58.635, Address=10.149.155.78:8088, MachineId=1102, Location=process:228, Role=CoherenceServer) ) RecycleMillis=120000 RecycleSet=MemberSet(Size=0, BitSetCount=0 ) ) At approximately 15:30, the connection between the two switches is severed: Thirty seconds later (the default packet timeout in development mode) the logs indicate communication failures across the cluster. In this example, the communication failure was caused by a network failure. In a production setting, this type of communication failure can have many root causes, including (but not limited to) network failures, excessive GC, high CPU utilization, swapping/virtual memory, and exceeding maximum network bandwidth. In addition, this type of failure is not necessarily indicative of a split brain. Any communication failure will be logged in this fashion. Member 2 logs a communication failure with Member 5: 2010-02-26 15:30:32.638/196.928 Oracle Coherence GE 3.5.3/465p2 <Warning> (thread=PacketPublisher, member=2): Timeout while delivering a packet; requesting the departure confirmation for Member(Id=5, Timestamp=2010-02-26 15:27:49.095, Address=10.149.155.79:8088, MachineId=1103, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:3229, Role=CoherenceServer) by MemberSet(Size=2, BitSetCount=2 Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) ) The Coherence clustering protocol (TCMP) is a reliable transport mechanism built on UDP. In order for the protocol to be reliable, it requires an acknowledgement (ACK) for each packet delivered. If a packet fails to be acknowledged within the configured timeout period, the Coherence cluster member will log a packet timeout (as seen in the log message above). When this occurs, the cluster member will consult with other members to determine who is at fault for the communication failure. If the witness members agree that the suspect member is at fault, the suspect is removed from the cluster. If the witnesses unanimously disagree, the accuser is removed. This process is known as the witness protocol. Since Member 2 cannot communicate with Member 5, it selects two witnesses (Members 1 and 4) to determine if the communication issue is with Member 5 or with itself (Member 2). However, Member 4 is on the switch that is no longer accessible by Members 1, 2 and 3; thus a packet timeout for member 4 is recorded as well: 2010-02-26 15:30:35.648/199.938 Oracle Coherence GE 3.5.3/465p2 <Warning> (thread=PacketPublisher, member=2): Timeout while delivering a packet; requesting the departure confirmation for Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) by MemberSet(Size=2, BitSetCount=2 Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) Member(Id=6, Timestamp=2010-02-26 15:27:58.635, Address=10.149.155.78:8088, MachineId=1102, Location=process:228, Role=CoherenceServer) ) Member 1 has the ability to confirm the departure of member 4, however Member 6 cannot as it is also inaccessible. At the same time, Member 3 sends a request to remove Member 6, which is followed by a report from Member 3 indicating that Member 6 has departed the cluster: 2010-02-26 15:30:35.706/199.996 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=2): MemberLeft request for Member 6 received from Member(Id=3, Timestamp=2010-02-26 15:27:24.892, Address=10.149.155.236:8088, MachineId=1260, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:32459, Role=CoherenceServer) 2010-02-26 15:30:35.709/199.999 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=2): MemberLeft notification for Member 6 received from Member(Id=3, Timestamp=2010-02-26 15:27:24.892, Address=10.149.155.236:8088, MachineId=1260, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:32459, Role=CoherenceServer) The log for Member 3 determines how Member 6 departed the cluster: 2010-02-26 15:30:35.161/191.694 Oracle Coherence GE 3.5.3/465p2 <Warning> (thread=PacketPublisher, member=3): Timeout while delivering a packet; requesting the departure confirmation for Member(Id=6, Timestamp=2010-02-26 15:27:58.635, Address=10.149.155.78:8088, MachineId=1102, Location=process:228, Role=CoherenceServer) by MemberSet(Size=2, BitSetCount=2 Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) Member(Id=2, Timestamp=2010-02-26 15:27:17.847, Address=10.149.155.77:8088, MachineId=1101, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:296, Role=CoherenceServer) ) 2010-02-26 15:30:35.165/191.698 Oracle Coherence GE 3.5.3/465p2 <Info> (thread=Cluster, member=3): Member departure confirmed by MemberSet(Size=2, BitSetCount=2 Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) Member(Id=2, Timestamp=2010-02-26 15:27:17.847, Address=10.149.155.77:8088, MachineId=1101, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:296, Role=CoherenceServer) ); removing Member(Id=6, Timestamp=2010-02-26 15:27:58.635, Address=10.149.155.78:8088, MachineId=1102, Location=process:228, Role=CoherenceServer) In this case, Member 3 happened to select two witnesses that it still had connectivity with (Members 1 and 2) thus resulting in a simple decision to remove Member 6. Given the departure of Member 6, Member 2 is left with a single witness to confirm the departure of Member 4: 2010-02-26 15:30:35.713/200.003 Oracle Coherence GE 3.5.3/465p2 <Info> (thread=Cluster, member=2): Member departure confirmed by MemberSet(Size=1, BitSetCount=2 Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) ); removing Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) In the meantime, Member 4 logs a missing heartbeat from the senior member. This message is also logged on Members 5 and 6. 2010-02-26 15:30:07.906/150.453 Oracle Coherence GE 3.5.3/465p2 <Info> (thread=PacketListenerN, member=4): Scheduled senior member heartbeat is overdue; rejoining multicast group. Next, Member 4 logs a TcpRing failure with Member 2, thus resulting in the termination of Member 2: 2010-02-26 15:30:21.421/163.968 Oracle Coherence GE 3.5.3/465p2 <D4> (thread=Cluster, member=4): TcpRing: Number of socket exceptions exceeded maximum; last was "java.net.SocketTimeoutException: connect timed out"; removing the member: 2 For quick process termination detection, Oracle Coherence utilizes a feature called TcpRing which is a sparse collection of TCP/IP-based connections between different members in the cluster. Each member in the cluster is connected to at least one other member, which (if at all possible) is running on a different physical box. This connection is not used for any data transfer, only heartbeat communications are sent once a second per each link. If a certain number of exceptions are thrown while trying to re-establish a connection, the member throwing the exceptions is removed from the cluster. Member 5 logs a packet timeout with Member 3 and cites witnesses Members 4 and 6: 2010-02-26 15:30:29.791/165.037 Oracle Coherence GE 3.5.3/465p2 <Warning> (thread=PacketPublisher, member=5): Timeout while delivering a packet; requesting the departure confirmation for Member(Id=3, Timestamp=2010-02-26 15:27:24.892, Address=10.149.155.236:8088, MachineId=1260, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:32459, Role=CoherenceServer) by MemberSet(Size=2, BitSetCount=2 Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) Member(Id=6, Timestamp=2010-02-26 15:27:58.635, Address=10.149.155.78:8088, MachineId=1102, Location=process:228, Role=CoherenceServer) ) 2010-02-26 15:30:29.798/165.044 Oracle Coherence GE 3.5.3/465p2 <Info> (thread=Cluster, member=5): Member departure confirmed by MemberSet(Size=2, BitSetCount=2 Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) Member(Id=6, Timestamp=2010-02-26 15:27:58.635, Address=10.149.155.78:8088, MachineId=1102, Location=process:228, Role=CoherenceServer) ); removing Member(Id=3, Timestamp=2010-02-26 15:27:24.892, Address=10.149.155.236:8088, MachineId=1260, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:32459, Role=CoherenceServer) Eventually we are left with two distinct clusters consisting of Members 1, 2, 3 and Members 4, 5, 6, respectively. In the latter cluster, Member 4 is promoted to senior member. The connection between the two switches is restored at 15:33. Upon the restoration of the connection, the cluster members immediately receive cluster heartbeats from the two senior members. In the case of Members 1, 2, and 3, the following is logged: 2010-02-26 15:33:14.970/369.066 Oracle Coherence GE 3.5.3/465p2 <Warning> (thread=Cluster, member=1): The member formerly known as Member(Id=4, Timestamp=2010-02-26 15:30:35.341, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) has been forcefully evicted from the cluster, but continues to emit a cluster heartbeat; henceforth, the member will be shunned and its messages will be ignored. Likewise for Members 4, 5, and 6: 2010-02-26 15:33:14.343/336.890 Oracle Coherence GE 3.5.3/465p2 <Warning> (thread=Cluster, member=4): The member formerly known as Member(Id=1, Timestamp=2010-02-26 15:30:31.64, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) has been forcefully evicted from the cluster, but continues to emit a cluster heartbeat; henceforth, the member will be shunned and its messages will be ignored. This message indicates that a senior heartbeat is being received from members that were previously removed from the cluster, in other words, something that should not be possible. For this reason, the recipients of these messages will initially ignore them. After several iterations of these messages, the existence of multiple clusters is acknowledged, thus triggering the panic protocol to reconcile this situation. When the presence of more than one cluster (i.e. Split-Brain) is detected by a Coherence member, the panic protocol is invoked in order to resolve the conflicting clusters and consolidate into a single cluster. The protocol consists of the removal of smaller clusters until there is one cluster remaining. In the case of equal size clusters, the one with the older Senior Member will survive. Member 1, being the oldest member, initiates the protocol: 2010-02-26 15:33:45.970/400.066 Oracle Coherence GE 3.5.3/465p2 <Warning> (thread=Cluster, member=1): An existence of a cluster island with senior Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) containing 3 nodes have been detected. Since this Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) is the senior of an older cluster island, the panic protocol is being activated to stop the other island's senior and all junior nodes that belong to it. Member 3 receives the panic: 2010-02-26 15:33:45.803/382.336 Oracle Coherence GE 3.5.3/465p2 <Error> (thread=Cluster, member=3): Received panic from senior Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer) caused by Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer) Member 4, the senior member of the younger cluster, receives the kill message from Member 3: 2010-02-26 15:33:44.921/367.468 Oracle Coherence GE 3.5.3/465p2 <Error> (thread=Cluster, member=4): Received a Kill message from a valid Member(Id=3, Timestamp=2010-02-26 15:27:24.892, Address=10.149.155.236:8088, MachineId=1260, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:32459, Role=CoherenceServer); stopping cluster service. In turn, Member 4 requests the departure of its junior members 5 and 6: 2010-02-26 15:33:44.921/367.468 Oracle Coherence GE 3.5.3/465p2 <Error> (thread=Cluster, member=4): Received a Kill message from a valid Member(Id=3, Timestamp=2010-02-26 15:27:24.892, Address=10.149.155.236:8088, MachineId=1260, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:32459, Role=CoherenceServer); stopping cluster service. 2010-02-26 15:33:43.343/349.015 Oracle Coherence GE 3.5.3/465p2 <Error> (thread=Cluster, member=6): Received a Kill message from a valid Member(Id=4, Timestamp=2010-02-26 15:27:39.574, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer); stopping cluster service. Once Members 4, 5, and 6 restart, they rejoin the original cluster with senior member 1. The log below is from Member 4. Note that it receives a different member id when it rejoins the cluster. 2010-02-26 15:33:44.921/367.468 Oracle Coherence GE 3.5.3/465p2 <Error> (thread=Cluster, member=4): Received a Kill message from a valid Member(Id=3, Timestamp=2010-02-26 15:27:24.892, Address=10.149.155.236:8088, MachineId=1260, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:32459, Role=CoherenceServer); stopping cluster service. 2010-02-26 15:33:46.921/369.468 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=4): Service Cluster left the cluster 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Invocation:InvocationService, member=4): Service InvocationService left the cluster 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=OptimisticCache, member=4): Service OptimisticCache left the cluster 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=ReplicatedCache, member=4): Service ReplicatedCache left the cluster 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=DistributedCache, member=4): Service DistributedCache left the cluster 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Invocation:Management, member=4): Service Management left the cluster 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=4): Member 6 left service Management with senior member 5 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=4): Member 6 left service DistributedCache with senior member 5 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=4): Member 6 left service ReplicatedCache with senior member 5 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=4): Member 6 left service OptimisticCache with senior member 5 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=4): Member 6 left service InvocationService with senior member 5 2010-02-26 15:33:47.046/369.593 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=4): Member(Id=6, Timestamp=2010-02-26 15:33:47.046, Address=10.149.155.78:8088, MachineId=1102, Location=process:228, Role=CoherenceServer) left Cluster with senior member 4 2010-02-26 15:33:49.218/371.765 Oracle Coherence GE 3.5.3/465p2 <Info> (thread=main, member=n/a): Restarting cluster 2010-02-26 15:33:49.421/371.968 Oracle Coherence GE 3.5.3/465p2 <D5> (thread=Cluster, member=n/a): Service Cluster joined the cluster with senior service member n/a 2010-02-26 15:33:49.625/372.172 Oracle Coherence GE 3.5.3/465p2 <Info> (thread=Cluster, member=n/a): This Member(Id=5, Timestamp=2010-02-26 15:33:50.499, Address=10.149.155.75:8088, MachineId=1099, Location=process:800, Role=CoherenceServer, Edition=Grid Edition, Mode=Development, CpuCount=2, SocketCount=1) joined cluster "cluster:0xDDEB" with senior Member(Id=1, Timestamp=2010-02-26 15:27:06.931, Address=10.149.155.76:8088, MachineId=1100, Location=site:usdhcp.oraclecorp.com,machine:dhcp-burlington6-4fl-east-10-149,process:511, Role=CoherenceServer, Edition=Grid Edition, Mode=Development, CpuCount=2, SocketCount=2) Cool isn't it?

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• Creating a dynamic proxy generator with c# – Part 3 – Creating the constructors

  - by SeanMcAlinden

  Creating a dynamic proxy generator with c# – Part 1 – Creating the Assembly builder, Module builder and caching mechanism Creating a dynamic proxy generator with c# – Part 2 – Interceptor Design For the latest code go to http://rapidioc.codeplex.com/ When building our proxy type, the first thing we need to do is build the constructors. There needs to be a corresponding constructor for each constructor on the passed in base type. We also want to create a field to store the interceptors and construct this list within each constructor. So assuming the passed in base type is a User<int, IRepository> class, were looking to generate constructor code like the following:   Default Constructor public User`2_RapidDynamicBaseProxy() {     this.interceptors = new List<IInterceptor<User<int, IRepository>>>();     DefaultInterceptor<User<int, IRepository>> item = new DefaultInterceptor<User<int, IRepository>>();     this.interceptors.Add(item); }     Parameterised Constructor public User`2_RapidDynamicBaseProxy(IRepository repository1) : base(repository1) {     this.interceptors = new List<IInterceptor<User<int, IRepository>>>();     DefaultInterceptor<User<int, IRepository>> item = new DefaultInterceptor<User<int, IRepository>>();     this.interceptors.Add(item); }   As you can see, we first populate a field on the class with a new list of the passed in base type. Construct our DefaultInterceptor class. Add the DefaultInterceptor instance to our interceptor collection. Although this seems like a relatively small task, there is a fair amount of work require to get this going. Instead of going through every line of code – please download the latest from http://rapidioc.codeplex.com/ and debug through. In this post I’m going to concentrate on explaining how it works. TypeBuilder The TypeBuilder class is the main class used to create the type. You instantiate a new TypeBuilder using the assembly module we created in part 1. /// <summary> /// Creates a type builder. /// </summary> /// <typeparam name="TBase">The type of the base class to be proxied.</typeparam> public static TypeBuilder CreateTypeBuilder<TBase>() where TBase : class {     TypeBuilder typeBuilder = DynamicModuleCache.Get.DefineType         (             CreateTypeName<TBase>(),             TypeAttributes.Class | TypeAttributes.Public,             typeof(TBase),             new Type[] { typeof(IProxy) }         );       if (typeof(TBase).IsGenericType)     {         GenericsHelper.MakeGenericType(typeof(TBase), typeBuilder);     }       return typeBuilder; }   private static string CreateTypeName<TBase>() where TBase : class {     return string.Format("{0}_RapidDynamicBaseProxy", typeof(TBase).Name); } As you can see, I’ve create a new public class derived from TBase which also implements my IProxy interface, this is used later for adding interceptors. If the base type is generic, the following GenericsHelper.MakeGenericType method is called. GenericsHelper using System; using System.Reflection.Emit; namespace Rapid.DynamicProxy.Types.Helpers {     /// <summary>     /// Helper class for generic types and methods.     /// </summary>     internal static class GenericsHelper     {         /// <summary>         /// Makes the typeBuilder a generic.         /// </summary>         /// <param name="concrete">The concrete.</param>         /// <param name="typeBuilder">The type builder.</param>         public static void MakeGenericType(Type baseType, TypeBuilder typeBuilder)         {             Type[] genericArguments = baseType.GetGenericArguments();               string[] genericArgumentNames = GetArgumentNames(genericArguments);               GenericTypeParameterBuilder[] genericTypeParameterBuilder                 = typeBuilder.DefineGenericParameters(genericArgumentNames);               typeBuilder.MakeGenericType(genericTypeParameterBuilder);         }           /// <summary>         /// Gets the argument names from an array of generic argument types.         /// </summary>         /// <param name="genericArguments">The generic arguments.</param>         public static string[] GetArgumentNames(Type[] genericArguments)         {             string[] genericArgumentNames = new string[genericArguments.Length];               for (int i = 0; i < genericArguments.Length; i++)             {                 genericArgumentNames[i] = genericArguments[i].Name;             }               return genericArgumentNames;         }     } }       As you can see, I’m getting all of the generic argument types and names, creating a GenericTypeParameterBuilder and then using the typeBuilder to make the new type generic. InterceptorsField The interceptors field will store a List<IInterceptor<TBase>>. Fields are simple made using the FieldBuilder class. The following code demonstrates how to create the interceptor field. FieldBuilder interceptorsField = typeBuilder.DefineField(     "interceptors",     typeof(System.Collections.Generic.List<>).MakeGenericType(typeof(IInterceptor<TBase>)),       FieldAttributes.Private     ); The field will now exist with the new Type although it currently has no data – we’ll deal with this in the constructor. Add method for interceptorsField To enable us to add to the interceptorsField list, we are going to utilise the Add method that already exists within the System.Collections.Generic.List class. We still however have to create the methodInfo necessary to call the add method. This can be done similar to the following: Add Interceptor Field MethodInfo addInterceptor = typeof(List<>)     .MakeGenericType(new Type[] { typeof(IInterceptor<>).MakeGenericType(typeof(TBase)) })     .GetMethod     (        "Add",        BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic,        null,        new Type[] { typeof(IInterceptor<>).MakeGenericType(typeof(TBase)) },        null     ); So we’ve create a List<IInterceptor<TBase>> type, then using the type created a method info called Add which accepts an IInterceptor<TBase>. Now in our constructor we can use this to call this.interceptors.Add(// interceptor); Building the Constructors This will be the first hard-core part of the proxy building process so I’m going to show the class and then try to explain what everything is doing. For a clear view, download the source from http://rapidioc.codeplex.com/, go to the test project and debug through the constructor building section. Anyway, here it is: DynamicConstructorBuilder using System; using System.Collections.Generic; using System.Reflection; using System.Reflection.Emit; using Rapid.DynamicProxy.Interception; using Rapid.DynamicProxy.Types.Helpers; namespace Rapid.DynamicProxy.Types.Constructors {     /// <summary>     /// Class for creating the proxy constructors.     /// </summary>     internal static class DynamicConstructorBuilder     {         /// <summary>         /// Builds the constructors.         /// </summary>         /// <typeparam name="TBase">The base type.</typeparam>         /// <param name="typeBuilder">The type builder.</param>         /// <param name="interceptorsField">The interceptors field.</param>         public static void BuildConstructors<TBase>             (                 TypeBuilder typeBuilder,                 FieldBuilder interceptorsField,                 MethodInfo addInterceptor             )             where TBase : class         {             ConstructorInfo interceptorsFieldConstructor = CreateInterceptorsFieldConstructor<TBase>();               ConstructorInfo defaultInterceptorConstructor = CreateDefaultInterceptorConstructor<TBase>();               ConstructorInfo[] constructors = typeof(TBase).GetConstructors();               foreach (ConstructorInfo constructorInfo in constructors)             {                 CreateConstructor<TBase>                     (                         typeBuilder,                         interceptorsField,                         interceptorsFieldConstructor,                         defaultInterceptorConstructor,                         addInterceptor,                         constructorInfo                     );             }         }           #region Private Methods           private static void CreateConstructor<TBase>             (                 TypeBuilder typeBuilder,                 FieldBuilder interceptorsField,                 ConstructorInfo interceptorsFieldConstructor,                 ConstructorInfo defaultInterceptorConstructor,                 MethodInfo AddDefaultInterceptor,                 ConstructorInfo constructorInfo             ) where TBase : class         {             Type[] parameterTypes = GetParameterTypes(constructorInfo);               ConstructorBuilder constructorBuilder = CreateConstructorBuilder(typeBuilder, parameterTypes);               ILGenerator cIL = constructorBuilder.GetILGenerator();               LocalBuilder defaultInterceptorMethodVariable =                 cIL.DeclareLocal(typeof(DefaultInterceptor<>).MakeGenericType(typeof(TBase)));               ConstructInterceptorsField(interceptorsField, interceptorsFieldConstructor, cIL);               ConstructDefaultInterceptor(defaultInterceptorConstructor, cIL, defaultInterceptorMethodVariable);               AddDefaultInterceptorToInterceptorsList                 (                     interceptorsField,                     AddDefaultInterceptor,                     cIL,                     defaultInterceptorMethodVariable                 );               CreateConstructor(constructorInfo, parameterTypes, cIL);         }           private static void CreateConstructor(ConstructorInfo constructorInfo, Type[] parameterTypes, ILGenerator cIL)         {             cIL.Emit(OpCodes.Ldarg_0);               if (parameterTypes.Length > 0)             {                 LoadParameterTypes(parameterTypes, cIL);             }               cIL.Emit(OpCodes.Call, constructorInfo);             cIL.Emit(OpCodes.Ret);         }           private static void LoadParameterTypes(Type[] parameterTypes, ILGenerator cIL)         {             for (int i = 1; i <= parameterTypes.Length; i++)             {                 cIL.Emit(OpCodes.Ldarg_S, i);             }         }           private static void AddDefaultInterceptorToInterceptorsList             (                 FieldBuilder interceptorsField,                 MethodInfo AddDefaultInterceptor,                 ILGenerator cIL,                 LocalBuilder defaultInterceptorMethodVariable             )         {             cIL.Emit(OpCodes.Ldarg_0);             cIL.Emit(OpCodes.Ldfld, interceptorsField);             cIL.Emit(OpCodes.Ldloc, defaultInterceptorMethodVariable);             cIL.Emit(OpCodes.Callvirt, AddDefaultInterceptor);         }           private static void ConstructDefaultInterceptor             (                 ConstructorInfo defaultInterceptorConstructor,                 ILGenerator cIL,                 LocalBuilder defaultInterceptorMethodVariable             )         {             cIL.Emit(OpCodes.Newobj, defaultInterceptorConstructor);             cIL.Emit(OpCodes.Stloc, defaultInterceptorMethodVariable);         }           private static void ConstructInterceptorsField             (                 FieldBuilder interceptorsField,                 ConstructorInfo interceptorsFieldConstructor,                 ILGenerator cIL             )         {             cIL.Emit(OpCodes.Ldarg_0);             cIL.Emit(OpCodes.Newobj, interceptorsFieldConstructor);             cIL.Emit(OpCodes.Stfld, interceptorsField);         }           private static ConstructorBuilder CreateConstructorBuilder(TypeBuilder typeBuilder, Type[] parameterTypes)         {             return typeBuilder.DefineConstructor                 (                     MethodAttributes.Public | MethodAttributes.SpecialName | MethodAttributes.RTSpecialName                     | MethodAttributes.HideBySig, CallingConventions.Standard, parameterTypes                 );         }           private static Type[] GetParameterTypes(ConstructorInfo constructorInfo)         {             ParameterInfo[] parameterInfoArray = constructorInfo.GetParameters();               Type[] parameterTypes = new Type[parameterInfoArray.Length];               for (int p = 0; p < parameterInfoArray.Length; p++)             {                 parameterTypes[p] = parameterInfoArray[p].ParameterType;             }               return parameterTypes;         }           private static ConstructorInfo CreateInterceptorsFieldConstructor<TBase>() where TBase : class         {             return ConstructorHelper.CreateGenericConstructorInfo                 (                     typeof(List<>),                     new Type[] { typeof(IInterceptor<TBase>) },                     BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic                 );         }           private static ConstructorInfo CreateDefaultInterceptorConstructor<TBase>() where TBase : class         {             return ConstructorHelper.CreateGenericConstructorInfo                 (                     typeof(DefaultInterceptor<>),                     new Type[] { typeof(TBase) },                     BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic                 );         }           #endregion     } } So, the first two tasks within the class should be fairly clear, we are creating a ConstructorInfo for the interceptorField list and a ConstructorInfo for the DefaultConstructor, this is for instantiating them in each contructor. We then using Reflection get an array of all of the constructors in the base class, we then loop through the array and create a corresponding proxy contructor. Hopefully, the code is fairly easy to follow other than some new types and the dreaded Opcodes. ConstructorBuilder This class defines a new constructor on the type. ILGenerator The ILGenerator allows the use of Reflection.Emit to create the method body. LocalBuilder The local builder allows the storage of data in local variables within a method, in this case it’s the constructed DefaultInterceptor. Constructing the interceptors field The first bit of IL you’ll come across as you follow through the code is the following private method used for constructing the field list of interceptors. private static void ConstructInterceptorsField             (                 FieldBuilder interceptorsField,                 ConstructorInfo interceptorsFieldConstructor,                 ILGenerator cIL             )         {             cIL.Emit(OpCodes.Ldarg_0);             cIL.Emit(OpCodes.Newobj, interceptorsFieldConstructor);             cIL.Emit(OpCodes.Stfld, interceptorsField);         } The first thing to know about generating code using IL is that you are using a stack, if you want to use something, you need to push it up the stack etc. etc. OpCodes.ldArg_0 This opcode is a really interesting one, basically each method has a hidden first argument of the containing class instance (apart from static classes), constructors are no different. This is the reason you can use syntax like this.myField. So back to the method, as we want to instantiate the List in the interceptorsField, first we need to load the class instance onto the stack, we then load the new object (new List<TBase>) and finally we store it in the interceptorsField. Hopefully, that should follow easily enough in the method. In each constructor you would now have this.interceptors = new List<User<int, IRepository>>(); Constructing and storing the DefaultInterceptor The next bit of code we need to create is the constructed DefaultInterceptor. Firstly, we create a local builder to store the constructed type. Create a local builder LocalBuilder defaultInterceptorMethodVariable =     cIL.DeclareLocal(typeof(DefaultInterceptor<>).MakeGenericType(typeof(TBase))); Once our local builder is ready, we then need to construct the DefaultInterceptor<TBase> and store it in the variable. Connstruct DefaultInterceptor private static void ConstructDefaultInterceptor     (         ConstructorInfo defaultInterceptorConstructor,         ILGenerator cIL,         LocalBuilder defaultInterceptorMethodVariable     ) {     cIL.Emit(OpCodes.Newobj, defaultInterceptorConstructor);     cIL.Emit(OpCodes.Stloc, defaultInterceptorMethodVariable); } As you can see, using the ConstructorInfo named defaultInterceptorConstructor, we load the new object onto the stack. Then using the store local opcode (OpCodes.Stloc), we store the new object in the local builder named defaultInterceptorMethodVariable. Add the constructed DefaultInterceptor to the interceptors field collection Using the add method created earlier in this post, we are going to add the new DefaultInterceptor object to the interceptors field collection. Add Default Interceptor private static void AddDefaultInterceptorToInterceptorsList     (         FieldBuilder interceptorsField,         MethodInfo AddDefaultInterceptor,         ILGenerator cIL,         LocalBuilder defaultInterceptorMethodVariable     ) {     cIL.Emit(OpCodes.Ldarg_0);     cIL.Emit(OpCodes.Ldfld, interceptorsField);     cIL.Emit(OpCodes.Ldloc, defaultInterceptorMethodVariable);     cIL.Emit(OpCodes.Callvirt, AddDefaultInterceptor); } So, here’s whats going on. The class instance is first loaded onto the stack using the load argument at index 0 opcode (OpCodes.Ldarg_0) (remember the first arg is the hidden class instance). The interceptorsField is then loaded onto the stack using the load field opcode (OpCodes.Ldfld). We then load the DefaultInterceptor object we stored locally using the load local opcode (OpCodes.Ldloc). Then finally we call the AddDefaultInterceptor method using the call virtual opcode (Opcodes.Callvirt). Completing the constructor The last thing we need to do is complete the constructor. Complete the constructor private static void CreateConstructor(ConstructorInfo constructorInfo, Type[] parameterTypes, ILGenerator cIL)         {             cIL.Emit(OpCodes.Ldarg_0);               if (parameterTypes.Length > 0)             {                 LoadParameterTypes(parameterTypes, cIL);             }               cIL.Emit(OpCodes.Call, constructorInfo);             cIL.Emit(OpCodes.Ret);         }           private static void LoadParameterTypes(Type[] parameterTypes, ILGenerator cIL)         {             for (int i = 1; i <= parameterTypes.Length; i++)             {                 cIL.Emit(OpCodes.Ldarg_S, i);             }         } So, the first thing we do again is load the class instance using the load argument at index 0 opcode (OpCodes.Ldarg_0). We then load each parameter using OpCode.Ldarg_S, this opcode allows us to specify an index position for each argument. We then setup calling the base constructor using OpCodes.Call and the base constructors ConstructorInfo. Finally, all methods are required to return, even when they have a void return. As there are no values on the stack after the OpCodes.Call line, we can safely call the OpCode.Ret to give the constructor a void return. If there was a value, we would have to pop the value of the stack before calling return otherwise, the method would try and return a value. Conclusion This was a slightly hardcore post but hopefully it hasn’t been too hard to follow. The main thing is that a number of the really useful opcodes have been used and now the dynamic proxy is capable of being constructed. If you download the code and debug through the tests at http://rapidioc.codeplex.com/, you’ll be able to create proxies at this point, they cannon do anything in terms of interception but you can happily run the tests, call base methods and properties and also take a look at the created assembly in Reflector. Hope this is useful. The next post should be up soon, it will be covering creating the private methods for calling the base class methods and properties. Kind Regards, Sean.

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• Entity Framework Code-First, OData & Windows Phone Client

  - by Jon Galloway

  Entity Framework Code-First is the coolest thing since sliced bread, Windows  Phone is the hottest thing since Tickle-Me-Elmo and OData is just too great to ignore. As part of the Full Stack project, we wanted to put them together, which turns out to be pretty easy… once you know how.   EF Code-First CTP5 is available now and there should be very few breaking changes in the release edition, which is due early in 2011.  Note: EF Code-First evolved rapidly and many of the existing documents and blog posts which were written with earlier versions, may now be obsolete or at least misleading.   Code-First? With traditional Entity Framework you start with a database and from that you generate “entities” – classes that bridge between the relational database and your object oriented program. With Code-First (Magic-Unicorn) (see Hanselman’s write up and this later write up by Scott Guthrie) the Entity Framework looks at classes you created and says “if I had created these classes, the database would have to have looked like this…” and creates the database for you! By deriving your entity collections from DbSet and exposing them via a class that derives from DbContext, you "turn on" database backing for your POCO with a minimum of code and no hidden designer or configuration files. POCO == Plain Old CLR Objects Your entity objects can be used throughout your applications - in web applications, console applications, Silverlight and Windows Phone applications, etc. In our case, we'll want to read and update data from a Windows Phone client application, so we'll expose the entities through a DataService and hook the Windows Phone client application to that data via proxies.  Piece of Pie.  Easy as cake. The Demo Architecture To see this at work, we’ll create an ASP.NET/MVC application which will act as the host for our Data Service.  We’ll create an incredibly simple data layer using EF Code-First on top of SQLCE4 and we’ll expose the data in a WCF Data Service using the oData protocol.  Our Windows Phone 7 client will instantiate  the data context via a URI and load the data asynchronously. Setting up the Server project with MVC 3, EF Code First, and SQL CE 4 Create a new application of type ASP.NET MVC 3 and name it DeadSimpleServer.  We need to add the latest SQLCE4 and Entity Framework Code First CTP's to our project. Fortunately, NuGet makes that really easy. Open the Package Manager Console (View / Other Windows / Package Manager Console) and type in "Install-Package EFCodeFirst.SqlServerCompact" at the PM> command prompt. Since NuGet handles dependencies for you, you'll see that it installs everything you need to use Entity Framework Code First in your project. PM> install-package EFCodeFirst.SqlServerCompact 'SQLCE (= 4.0.8435.1)' not installed. Attempting to retrieve dependency from source... Done 'EFCodeFirst (= 0.8)' not installed. Attempting to retrieve dependency from source... Done 'WebActivator (= 1.0.0.0)' not installed. Attempting to retrieve dependency from source... Done You are downloading SQLCE from Microsoft, the license agreement to which is available at http://173.203.67.148/licenses/SQLCE/EULA_ENU.rtf. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'SQLCE 4.0.8435.1' You are downloading EFCodeFirst from Microsoft, the license agreement to which is available at http://go.microsoft.com/fwlink/?LinkID=206497. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'EFCodeFirst 0.8' Successfully installed 'WebActivator 1.0.0.0' You are downloading EFCodeFirst.SqlServerCompact from Microsoft, the license agreement to which is available at http://173.203.67.148/licenses/SQLCE/EULA_ENU.rtf. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'EFCodeFirst.SqlServerCompact 0.8' Successfully added 'SQLCE 4.0.8435.1' to EfCodeFirst-CTP5 Successfully added 'EFCodeFirst 0.8' to EfCodeFirst-CTP5 Successfully added 'WebActivator 1.0.0.0' to EfCodeFirst-CTP5 Successfully added 'EFCodeFirst.SqlServerCompact 0.8' to EfCodeFirst-CTP5 Note: We're using SQLCE 4 with Entity Framework here because they work really well together from a development scenario, but you can of course use Entity Framework Code First with other databases supported by Entity framework. Creating The Model using EF Code First Now we can create our model class. Right-click the Models folder and select Add/Class. Name the Class Person.cs and add the following code: using System.Data.Entity; namespace DeadSimpleServer.Models { public class Person { public int ID { get; set; } public string Name { get; set; } } public class PersonContext : DbContext { public DbSet<Person> People { get; set; } } } Notice that the entity class Person has no special interfaces or base class. There's nothing special needed to make it work - it's just a POCO. The context we'll use to access the entities in the application is called PersonContext, but you could name it anything you wanted. The important thing is that it inherits DbContext and contains one or more DbSet which holds our entity collections. Adding Seed Data We need some testing data to expose from our service. The simplest way to get that into our database is to modify the CreateCeDatabaseIfNotExists class in AppStart_SQLCEEntityFramework.cs by adding some seed data to the Seed method: protected virtual void Seed( TContext context ) { var personContext = context as PersonContext; personContext.People.Add( new Person { ID = 1, Name = "George Washington" } ); personContext.People.Add( new Person { ID = 2, Name = "John Adams" } ); personContext.People.Add( new Person { ID = 3, Name = "Thomas Jefferson" } ); personContext.SaveChanges(); } The CreateCeDatabaseIfNotExists class name is pretty self-explanatory - when our DbContext is accessed and the database isn't found, a new one will be created and populated with the data in the Seed method. There's one more step to make that work - we need to uncomment a line in the Start method at the top of of the AppStart_SQLCEEntityFramework class and set the context name, as shown here, public static class AppStart_SQLCEEntityFramework { public static void Start() { DbDatabase.DefaultConnectionFactory = new SqlCeConnectionFactory("System.Data.SqlServerCe.4.0"); // Sets the default database initialization code for working with Sql Server Compact databases // Uncomment this line and replace CONTEXT_NAME with the name of your DbContext if you are // using your DbContext to create and manage your database DbDatabase.SetInitializer(new CreateCeDatabaseIfNotExists<PersonContext>()); } } Now our database and entity framework are set up, so we can expose data via WCF Data Services. Note: This is a bare-bones implementation with no administration screens. If you'd like to see how those are added, check out The Full Stack screencast series. Creating the oData Service using WCF Data Services Add a new WCF Data Service to the project (right-click the project / Add New Item / Web / WCF Data Service). We’ll be exposing all the data as read/write.  Remember to reconfigure to control and minimize access as appropriate for your own application. Open the code behind for your service. In our case, the service was called PersonTestDataService.svc so the code behind class file is PersonTestDataService.svc.cs. using System.Data.Services; using System.Data.Services.Common; using System.ServiceModel; using DeadSimpleServer.Models; namespace DeadSimpleServer { [ServiceBehavior( IncludeExceptionDetailInFaults = true )] public class PersonTestDataService : DataService<PersonContext> { // This method is called only once to initialize service-wide policies. public static void InitializeService( DataServiceConfiguration config ) { config.SetEntitySetAccessRule( "*", EntitySetRights.All ); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; config.UseVerboseErrors = true; } } } We're enabling a few additional settings to make it easier to debug if you run into trouble. The ServiceBehavior attribute is set to include exception details in faults, and we're using verbose errors. You can remove both of these when your service is working, as your public production service shouldn't be revealing exception information. You can view the output of the service by running the application and browsing to http://localhost:[portnumber]/PersonTestDataService.svc/: <service xml:base="http://localhost:49786/PersonTestDataService.svc/" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:app="http://www.w3.org/2007/app" xmlns="http://www.w3.org/2007/app"> <workspace> <atom:title>Default</atom:title> <collection href="People"> <atom:title>People</atom:title> </collection> </workspace> </service> This indicates that the service exposes one collection, which is accessible by browsing to http://localhost:[portnumber]/PersonTestDataService.svc/People <?xml version="1.0" encoding="iso-8859-1" standalone="yes"?> <feed xml:base=http://localhost:49786/PersonTestDataService.svc/ xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns="http://www.w3.org/2005/Atom"> <title type="text">People</title> <id>http://localhost:49786/PersonTestDataService.svc/People</id> <updated>2010-12-29T01:01:50Z</updated> <link rel="self" title="People" href="People" /> <entry> <id>http://localhost:49786/PersonTestDataService.svc/People(1)</id> <title type="text"></title> <updated>2010-12-29T01:01:50Z</updated> <author> <name /> </author> <link rel="edit" title="Person" href="People(1)" /> <category term="DeadSimpleServer.Models.Person" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" /> <content type="application/xml"> <m:properties> <d:ID m:type="Edm.Int32">1</d:ID> <d:Name>George Washington</d:Name> </m:properties> </content> </entry> <entry> ... </entry> </feed> Let's recap what we've done so far. But enough with services and XML - let's get this into our Windows Phone client application. Creating the DataServiceContext for the Client Use the latest DataSvcUtil.exe from http://odata.codeplex.com. As of today, that's in this download: http://odata.codeplex.com/releases/view/54698 You need to run it with a few options: /uri - This will point to the service URI. In this case, it's http://localhost:59342/PersonTestDataService.svc  Pick up the port number from your running server (e.g., the server formerly known as Cassini). /out - This is the DataServiceContext class that will be generated. You can name it whatever you'd like. /Version - should be set to 2.0 /DataServiceCollection - Include this flag to generate collections derived from the DataServiceCollection base, which brings in all the ObservableCollection goodness that handles your INotifyPropertyChanged events for you. Here's the console session from when we ran it: <ListBox x:Name="MainListBox" Margin="0,0,-12,0" ItemsSource="{Binding}" SelectionChanged="MainListBox_SelectionChanged"> Next, to keep things simple, change the Binding on the two TextBlocks within the DataTemplate to Name and ID, <ListBox x:Name="MainListBox" Margin="0,0,-12,0" ItemsSource="{Binding}" SelectionChanged="MainListBox_SelectionChanged"> <ListBox.ItemTemplate> <DataTemplate> <StackPanel Margin="0,0,0,17" Width="432"> <TextBlock Text="{Binding Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextExtraLargeStyle}" /> <TextBlock Text="{Binding ID}" TextWrapping="Wrap" Margin="12,-6,12,0" Style="{StaticResource PhoneTextSubtleStyle}" /> </StackPanel> </DataTemplate> </ListBox.ItemTemplate> </ListBox> Getting The Context In the code-behind you’ll first declare a member variable to hold the context from the Entity Framework. This is named using convention over configuration. The db type is Person and the context is of type PersonContext, You initialize it by providing the URI, in this case using the URL obtained from the Cassini web server, PersonContext context = new PersonContext( new Uri( "http://localhost:49786/PersonTestDataService.svc/" ) ); Create a second member variable of type DataServiceCollection<Person> but do not initialize it, DataServiceCollection<Person> people; In the constructor you’ll initialize the DataServiceCollection using the PersonContext, public MainPage() { InitializeComponent(); people = new DataServiceCollection<Person>( context ); Finally, you’ll load the people collection using the LoadAsync method, passing in the fully specified URI for the People collection in the web service, people.LoadAsync( new Uri( "http://localhost:49786/PersonTestDataService.svc/People" ) ); Note that this method runs asynchronously and when it is finished the people  collection is already populated. Thus, since we didn’t need or want to override any of the behavior we don’t implement the LoadCompleted. You can use the LoadCompleted event if you need to do any other UI updates, but you don't need to. The final code is as shown below: using System; using System.Data.Services.Client; using System.Windows; using System.Windows.Controls; using DeadSimpleServer.Models; using Microsoft.Phone.Controls; namespace WindowsPhoneODataTest { public partial class MainPage : PhoneApplicationPage { PersonContext context = new PersonContext( new Uri( "http://localhost:49786/PersonTestDataService.svc/" ) ); DataServiceCollection<Person> people; // Constructor public MainPage() { InitializeComponent(); // Set the data context of the listbox control to the sample data // DataContext = App.ViewModel; people = new DataServiceCollection<Person>( context ); people.LoadAsync( new Uri( "http://localhost:49786/PersonTestDataService.svc/People" ) ); DataContext = people; this.Loaded += new RoutedEventHandler( MainPage_Loaded ); } // Handle selection changed on ListBox private void MainListBox_SelectionChanged( object sender, SelectionChangedEventArgs e ) { // If selected index is -1 (no selection) do nothing if ( MainListBox.SelectedIndex == -1 ) return; // Navigate to the new page NavigationService.Navigate( new Uri( "/DetailsPage.xaml?selectedItem=" + MainListBox.SelectedIndex, UriKind.Relative ) ); // Reset selected index to -1 (no selection) MainListBox.SelectedIndex = -1; } // Load data for the ViewModel Items private void MainPage_Loaded( object sender, RoutedEventArgs e ) { if ( !App.ViewModel.IsDataLoaded ) { App.ViewModel.LoadData(); } } } } With people populated we can set it as the DataContext and run the application; you’ll find that the Name and ID are displayed in the list on the Mainpage. Here's how the pieces in the client fit together: Complete source code available here

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• JMS Step 4 - How to Create an 11g BPEL Process Which Writes a Message Based on an XML Schema to a JMS Queue

  - by John-Brown.Evans

  JMS Step 4 - How to Create an 11g BPEL Process Which Writes a Message Based on an XML Schema to a JMS Queue ol{margin:0;padding:0} .c11_4{vertical-align:top;width:129.8pt;border-style:solid;background-color:#f3f3f3;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c9_4{vertical-align:top;width:207pt;border-style:solid;background-color:#f3f3f3;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt}.c14{vertical-align:top;width:207pt;border-style:solid;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c17_4{vertical-align:top;width:129.8pt;border-style:solid;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c7_4{vertical-align:top;width:130pt;border-style:solid;border-color:#000000;border-width:1pt;padding:0pt 5pt 0pt 5pt} .c19_4{vertical-align:top;width:468pt;border-style:solid;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c22_4{background-color:#ffffff} .c20_4{list-style-type:disc;margin:0;padding:0} .c6_4{font-size:8pt;font-family:"Courier New"} .c24_4{color:inherit;text-decoration:inherit} .c23_4{color:#1155cc;text-decoration:underline} .c0_4{height:11pt;direction:ltr} .c10_4{font-size:10pt;font-family:"Courier New"} .c3_4{padding-left:0pt;margin-left:36pt} .c18_4{font-size:8pt} .c8_4{text-align:center} .c12_4{background-color:#ffff00} .c2_4{font-weight:bold} .c21_4{background-color:#00ff00} .c4_4{line-height:1.0} .c1_4{direction:ltr} .c15_4{background-color:#f3f3f3} .c13_4{font-family:"Courier New"} .c5_4{font-style:italic} .c16_4{border-collapse:collapse} .title{padding-top:24pt;line-height:1.15;text-align:left;color:#000000;font-size:36pt;font-family:"Arial";font-weight:bold;padding-bottom:6pt} .subtitle{padding-top:18pt;line-height:1.15;text-align:left;color:#666666;font-style:italic;font-size:24pt;font-family:"Georgia";padding-bottom:4pt} li{color:#000000;font-size:10pt;font-family:"Arial"} p{color:#000000;font-size:10pt;margin:0;font-family:"Arial"} h1{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:18pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h2{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:18pt;font-family:"Arial";font-weight:bold;padding-bottom:0pt} h3{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:14pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h4{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-style:italic;font-size:11pt;font-family:"Arial";padding-bottom:0pt} h5{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:10pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h6{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-style:italic;font-size:10pt;font-family:"Arial";padding-bottom:0pt} This post continues the series of JMS articles which demonstrate how to use JMS queues in a SOA context. The previous posts were: JMS Step 1 - How to Create a Simple JMS Queue in Weblogic Server 11g JMS Step 2 - Using the QueueSend.java Sample Program to Send a Message to a JMS Queue JMS Step 3 - Using the QueueReceive.java Sample Program to Read a Message from a JMS Queue In this example we will create a BPEL process which will write (enqueue) a message to a JMS queue using a JMS adapter. The JMS adapter will enqueue the full XML payload to the queue. This sample will use the following WebLogic Server objects. The first two, the Connection Factory and JMS Queue, were created as part of the first blog post in this series, JMS Step 1 - How to Create a Simple JMS Queue in Weblogic Server 11g. If you haven't created those objects yet, please see that post for details on how to do so. The Connection Pool will be created as part of this example. Object Name Type JNDI Name TestConnectionFactory Connection Factory jms/TestConnectionFactory TestJMSQueue JMS Queue jms/TestJMSQueue eis/wls/TestQueue Connection Pool eis/wls/TestQueue 1. Verify Connection Factory and JMS Queue As mentioned above, this example uses a WLS Connection Factory called TestConnectionFactory and a JMS queue TestJMSQueue. As these are prerequisites for this example, let us verify they exist. Log in to the WebLogic Server Administration Console. Select Services > JMS Modules > TestJMSModule You should see the following objects: If not, or if the TestJMSModule is missing, please see the abovementioned article and create these objects before continuing. 2. Create a JMS Adapter Connection Pool in WebLogic Server The BPEL process we are about to create uses a JMS adapter to write to the JMS queue. The JMS adapter is deployed to the WebLogic server and needs to be configured to include a connection pool which references the connection factory associated with the JMS queue. In the WebLogic Server Console Go to Deployments > Next and select (click on) the JmsAdapter Select Configuration > Outbound Connection Pools and expand oracle.tip.adapter.jms.IJmsConnectionFactory. This will display the list of connections configured for this adapter. For example, eis/aqjms/Queue, eis/aqjms/Topic etc. These JNDI names are actually quite confusing. We are expecting to configure a connection pool here, but the names refer to queues and topics. One would expect these to be called *ConnectionPool or *_CF or similar, but to conform to this nomenclature, we will call our entry eis/wls/TestQueue . This JNDI name is also the name we will use later, when creating a BPEL process to access this JMS queue! Select New, check the oracle.tip.adapter.jms.IJmsConnectionFactory check box and Next. Enter JNDI Name: eis/wls/TestQueue for the connection instance, then press Finish. Expand oracle.tip.adapter.jms.IJmsConnectionFactory again and select (click on) eis/wls/TestQueue The ConnectionFactoryLocation must point to the JNDI name of the connection factory associated with the JMS queue you will be writing to. In our example, this is the connection factory called TestConnectionFactory, with the JNDI name jms/TestConnectionFactory.( As a reminder, this connection factory is contained in the JMS Module called TestJMSModule, under Services > Messaging > JMS Modules > TestJMSModule which we verified at the beginning of this document. )Enter jms/TestConnectionFactory  into the Property Value field for Connection Factory Location. After entering it, you must press Return/Enter then Save for the value to be accepted. If your WebLogic server is running in Development mode, you should see the message that the changes have been activated and the deployment plan successfully updated. If not, then you will manually need to activate the changes in the WebLogic server console. Although the changes have been activated, the JmsAdapter needs to be redeployed in order for the changes to become effective. This should be confirmed by the message Remember to update your deployment to reflect the new plan when you are finished with your changes as can be seen in the following screen shot: The next step is to redeploy the JmsAdapter.Navigate back to the Deployments screen, either by selecting it in the left-hand navigation tree or by selecting the “Summary of Deployments” link in the breadcrumbs list at the top of the screen. Then select the checkbox next to JmsAdapter and press the Update button On the Update Application Assistant page, select “Redeploy this application using the following deployment files” and press Finish. After a few seconds you should get the message that the selected deployments were updated. The JMS adapter configuration is complete and it can now be used to access the JMS queue. To summarize: we have created a JMS adapter connection pool connector with the JNDI name jms/TestConnectionFactory. This is the JNDI name to be accessed by a process such as a BPEL process, when using the JMS adapter to access the previously created JMS queue with the JNDI name jms/TestJMSQueue. In the following step, we will set up a BPEL process to use this JMS adapter to write to the JMS queue. 3. Create a BPEL Composite with a JMS Adapter Partner Link This step requires that you have a valid Application Server Connection defined in JDeveloper, pointing to the application server on which you created the JMS Queue and Connection Factory. You can create this connection in JDeveloper under the Application Server Navigator. Give it any name and be sure to test the connection before completing it. This sample will use the connection name jbevans-lx-PS5, as that is the name of the connection pointing to my SOA PS5 installation. When using a JMS adapter from within a BPEL process, there are various configuration options, such as the operation type (consume message, produce message etc.), delivery mode and message type. One of these options is the choice of the format of the JMS message payload. This can be structured around an existing XSD, in which case the full XML element and tags are passed, or it can be opaque, meaning that the payload is sent as-is to the JMS adapter. In the case of an XSD-based message, the payload can simply be copied to the input variable of the JMS adapter. In the case of an opaque message, the JMS adapter’s input variable is of type base64binary. So the payload needs to be converted to base64 binary first. I will go into this in more detail in a later blog entry. This sample will pass a simple message to the adapter, based on the following simple XSD file, which consists of a single string element: stringPayload.xsd <?xml version="1.0" encoding="windows-1252" ?> <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://www.example.org" targetNamespace="http://www.example.org" elementFormDefault="qualified" <xsd:element name="exampleElement" type="xsd:string"> </xsd:element> </xsd:schema> The following steps are all executed in JDeveloper. The SOA project will be created inside a JDeveloper Application. If you do not already have an application to contain the project, you can create a new one via File > New > General > Generic Application. Give the application any name, for example JMSTests and, when prompted for a project name and type, call the project JmsAdapterWriteWithXsd and select SOA as the project technology type. If you already have an application, continue below. Create a SOA Project Create a new project and choose SOA Tier > SOA Project as its type. Name it JmsAdapterWriteSchema. When prompted for the composite type, choose Composite With BPEL Process. When prompted for the BPEL Process, name it JmsAdapterWriteSchema too and choose Synchronous BPEL Process as the template. This will create a composite with a BPEL process and an exposed SOAP service. Double-click the BPEL process to open and begin editing it. You should see a simple BPEL process with a Receive and Reply activity. As we created a default process without an XML schema, the input and output variables are simple strings. Create an XSD File An XSD file is required later to define the message format to be passed to the JMS adapter. In this step, we create a simple XSD file, containing a string variable and add it to the project. First select the xsd item in the left-hand navigation tree to ensure that the XSD file is created under that item. Select File > New > General > XML and choose XML Schema. Call it stringPayload.xsd and when the editor opens, select the Source view. then replace the contents with the contents of the stringPayload.xsd example above and save the file. You should see it under the xsd item in the navigation tree. Create a JMS Adapter Partner Link We will create the JMS adapter as a service at the composite level. If it is not already open, double-click the composite.xml file in the navigator to open it. From the Component Palette, drag a JMS adapter over onto the right-hand swim lane, under External References. This will start the JMS Adapter Configuration Wizard. Use the following entries: Service Name: JmsAdapterWrite Oracle Enterprise Messaging Service (OEMS): Oracle Weblogic JMS AppServer Connection: Use an existing application server connection pointing to the WebLogic server on which the above JMS queue and connection factory were created. You can use the “+” button to create a connection directly from the wizard, if you do not already have one. This example uses a connection called jbevans-lx-PS5. Adapter Interface > Interface: Define from operation and schema (specified later) Operation Type: Produce Message Operation Name: Produce_message Destination Name: Press the Browse button, select Destination Type: Queues, then press Search. Wait for the list to populate, then select the entry for TestJMSQueue , which is the queue created earlier. JNDI Name: The JNDI name to use for the JMS connection. This is probably the most important step in this exercise and the most common source of error. This is the JNDI name of the JMS adapter’s connection pool created in the WebLogic Server and which points to the connection factory. JDeveloper does not verify the value entered here. If you enter a wrong value, the JMS adapter won’t find the queue and you will get an error message at runtime, which is very difficult to trace. In our example, this is the value eis/wls/TestQueue . (See the earlier step on how to create a JMS Adapter Connection Pool in WebLogic Server for details.) MessagesURL: We will use the XSD file we created earlier, stringPayload.xsd to define the message format for the JMS adapter. Press the magnifying glass icon to search for schema files. Expand Project Schema Files > stringPayload.xsd and select exampleElement: string. Press Next and Finish, which will complete the JMS Adapter configuration. Wire the BPEL Component to the JMS Adapter In this step, we link the BPEL process/component to the JMS adapter. From the composite.xml editor, drag the right-arrow icon from the BPEL process to the JMS adapter’s in-arrow. This completes the steps at the composite level. 4. Complete the BPEL Process Design Invoke the JMS Adapter Open the BPEL component by double-clicking it in the design view of the composite.xml, or open it from the project navigator by selecting the JmsAdapterWriteSchema.bpel file. This will display the BPEL process in the design view. You should see the JmsAdapterWrite partner link under one of the two swim lanes. We want it in the right-hand swim lane. If JDeveloper displays it in the left-hand lane, right-click it and choose Display > Move To Opposite Swim Lane. An Invoke activity is required in order to invoke the JMS adapter. Drag an Invoke activity between the Receive and Reply activities. Drag the right-hand arrow from the Invoke activity to the JMS adapter partner link. This will open the Invoke editor. The correct default values are entered automatically and are fine for our purposes. We only need to define the input variable to use for the JMS adapter. By pressing the green “+” symbol, a variable of the correct type can be auto-generated, for example with the name Invoke1_Produce_Message_InputVariable. Press OK after creating the variable. ( For some reason, while I was testing this, the JMS Adapter moved back to the left-hand swim lane again after this step. There is no harm in leaving it there, but I find it easier to follow if it is in the right-hand lane, because I kind-of think of the message coming in on the left and being routed through the right. But you can follow your personal preference here.) Assign Variables Drag an Assign activity between the Receive and Invoke activities. We will simply copy the input variable to the JMS adapter and, for completion, so the process has an output to print, again to the process’s output variable. Double-click the Assign activity and create two Copy rules: for the first, drag Variables > inputVariable > payload > client:process > client:input_string to Invoke1_Produce_Message_InputVariable > body > ns2:exampleElement for the second, drag the same input variable to outputVariable > payload > client:processResponse > client:result This will create two copy rules, similar to the following: Press OK. This completes the BPEL and Composite design. 5. Compile and Deploy the Composite We won’t go into too much detail on how to compile and deploy. In JDeveloper, compile the process by pressing the Make or Rebuild icons or by right-clicking the project name in the navigator and selecting Make... or Rebuild... If the compilation is successful, deploy it to the SOA server connection defined earlier. (Right-click the project name in the navigator, select Deploy to Application Server, choose the application server connection, choose the partition on the server (usually default) and press Finish. You should see the message ---- Deployment finished. ---- in the Deployment frame, if the deployment was successful. 6. Test the Composite This is the exciting part. Open two tabs in your browser and log in to the WebLogic Administration Console in one tab and the Enterprise Manager 11g Fusion Middleware Control (EM) for your SOA installation in the other. We will use the Console to monitor the messages being written to the queue and the EM to execute the composite. In the Console, go to Services > Messaging > JMS Modules > TestJMSModule > TestJMSQueue > Monitoring. Note the number of messages under Messages Current. In the EM, go to SOA > soa-infra (soa_server1) > default (or wherever you deployed your composite to) and click on JmsAdapterWriteSchema [1.0], then press the Test button. Under Input Arguments, enter any string into the text input field for the payload, for example Test Message then press Test Web Service. If the instance is successful you should see the same text in the Response message, “Test Message”. In the Console, refresh the Monitoring screen to confirm a new message has been written to the queue. Check the checkbox and press Show Messages. Click on the newest message and view its contents. They should include the full XML of the entered payload. 7. Troubleshooting If you get an exception similar to the following at runtime ... BINDING.JCA-12510 JCA Resource Adapter location error. Unable to locate the JCA Resource Adapter via .jca binding file element The JCA Binding Component is unable to startup the Resource Adapter specified in the element: location='eis/wls/QueueTest'. The reason for this is most likely that either 1) the Resource Adapters RAR file has not been deployed successfully to the WebLogic Application server or 2) the '' element in weblogic-ra.xml has not been set to eis/wls/QueueTest. In the last case you will have to add a new WebLogic JCA connection factory (deploy a RAR). Please correct this and then restart the Application Server at oracle.integration.platform.blocks.adapter.fw.AdapterBindingException. createJndiLookupException(AdapterBindingException.java:130) at oracle.integration.platform.blocks.adapter.fw.jca.cci. JCAConnectionManager$JCAConnectionPool.createJCAConnectionFactory (JCAConnectionManager.java:1387) at oracle.integration.platform.blocks.adapter.fw.jca.cci. JCAConnectionManager$JCAConnectionPool.newPoolObject (JCAConnectionManager.java:1285) ... then this is very likely due to an incorrect JNDI name entered for the JMS Connection in the JMS Adapter Wizard. Recheck those steps. The error message prints the name of the JNDI name used. In this example, it was incorrectly entered as eis/wls/QueueTest instead of eis/wls/TestQueue. This concludes this example. Best regards John-Brown Evans Oracle Technology Proactive Support Delivery

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• What Every Developer Should Know About MSI Components

  - by Alois Kraus

  Hopefully nothing. But if you have to do more than simple XCopy deployment and you need to support updates, upgrades and perhaps side by side scenarios there is no way around MSI. You can create Msi files with a Visual Studio Setup project which is severely limited or you can use the Windows Installer Toolset. I cannot talk about WIX with my German colleagues because WIX has a very special meaning. It is funny to always use the long name when I talk about deployment possibilities. Alternatively you can buy commercial tools which help you to author Msi files but I am not sure how good they are. Given enough pain with existing solutions you can also learn the MSI Apis and create your own packaging solution. If I were you I would use either a commercial visual tool when you do easy deployments or use the free Windows Installer Toolset. Once you know the WIX schema you can create well formed wix xml files easily with any editor. Then you can “compile” from the wxs files your Msi package. Recently I had the “pleasure” to get my hands dirty with C++ (again) and the MSI technology. Installation is a complex topic but after several month of digging into arcane MSI issues I can safely say that there should exist an easier way to install and update files as today. I am not alone with this statement as John Robbins (creator of the cool tool Paraffin) states: “.. It's a brittle and scary API in Windows …”. To help other people struggling with installation issues I present you the advice I (and others) found useful and what will happen if you ignore this advice. What is a MSI file? A MSI file is basically a database with tables which reference each other to control how your un/installation should work. The basic idea is that you declare via these tables what you want to install and MSI controls the how to get your stuff onto or off your machine. Your “stuff” consists usually of files, registry keys, shortcuts and environment variables. Therefore the most important tables are File, Registry, Environment and Shortcut table which define what will be un/installed. The key to master MSI is that every resource (file, registry key ,…) is associated with a MSI component. The actual payload consists of compressed files in the CAB format which can either be embedded into the MSI file or reside beside the MSI file or in a subdirectory below it. To examine MSI files you need Orca a free MSI editor provided by MS. There is also another free editor called Super Orca which does support diffs between MSI and it does not lock the MSI files. But since Orca comes with a shell extension I tend to use only Orca because it is so easy to right click on a MSI file and open it with this tool. How Do I Install It? Double click it. This does work for fresh installations as well as major upgrades. Updates need to be installed via the command line via msiexec /i <msi> REINSTALL=ALL REINSTALLMODE=vomus   This tells the installer to reinstall all already installed features (new features will NOT be installed). The reinstallmode letters do force an overwrite of the old cached package in the %WINDIR%\Installer folder. All files, shortcuts and registry keys are redeployed if they are missing or need to be replaced with a newer version. When things did go really wrong and you want to overwrite everything unconditionally use REINSTALLMODE=vamus. How To Enable MSI Logs? You can download a MSI from Microsoft which installs some registry keys to enable full MSI logging. The log files can be found in your %TEMP% folder and are called MSIxxxx.log. Alternatively you can add to your msiexec command line the option msiexec …. /l*vx <LogFileName> Personally I find it rather strange that * does not mean full logging. To really get all logs I need to add v and x which is documented in the msiexec help but I still find this behavior unintuitive. What are MSI components? The whole MSI logic is bound to the concept of MSI components. Nearly every msi table has a Component column which binds an installable resource to a component. Below are the screenshots of the FeatureComponents and Component table of an example MSI. The Feature table defines basically the feature hierarchy.  To find out what belongs to a feature you need to look at the FeatureComponents table where for each feature the components are listed which will be installed when a feature is installed. The MSI components are defined in the  Component table. This table has as first column the component name and as second column the component id which is a GUID. All resources you want to install belong to a MSI component. Therefore nearly all MSI tables have a Component_ column which contains the component name. If you look e.g. a the File table you see that every file belongs to a component which is true for all other tables which install resources. The component table is the glue between all other tables which contain the resources you want to install. So far so easy. Why is MSI then so complex? Most MSI problems arise from the fact that you did violate a MSI component rule in one or the other way. When you install a feature the reference count for all components belonging to this feature will increase by one. If your component is installed by more than one feature it will get a higher refcount. When you uninstall a feature its refcount will drop by one. Interesting things happen if the component reference count reaches zero: Then all associated resources will be deleted. That looks like a reasonable thing and it is. What it makes complex are the strange component rules you have to follow. Below are some important component rules from the Tao of the Windows Installer … Rule 16: Follow Component Rules Components are a very important part of the Installer technology. They are the means whereby the Installer manages the resources that make up your application. The SDK provides the following guidelines for creating components in your package: Never create two components that install a resource under the same name and target location. If a resource must be duplicated in multiple components, change its name or target location in each component. This rule should be applied across applications, products, product versions, and companies. Two components must not have the same key path file. This is a consequence of the previous rule. The key path value points to a particular file or folder belonging to the component that the installer uses to detect the component. If two components had the same key path file, the installer would be unable to distinguish which component is installed. Two components however may share a key path folder. Do not create a version of a component that is incompatible with all previous versions of the component. This rule should be applied across applications, products, product versions, and companies. Do not create components containing resources that will need to be installed into more than one directory on the user’s system. The installer installs all of the resources in a component into the same directory. It is not possible to install some resources into subdirectories. Do not include more than one COM server per component. If a component contains a COM server, this must be the key path for the component. Do not specify more than one file per component as a target for the Start menu or a Desktop shortcut. … And these rules do not even talk about component ids, update packages and upgrades which you need to understand as well. Lets suppose you install two MSIs (MSI1 and MSI2) which have the same ComponentId but different component names. Both do install the same file. What will happen when you uninstall MSI2?   Hm the file should stay there. But the component names are different. Yes and yes. But MSI uses not use the component name as key for the refcount. Instead the ComponentId column of the Component table which contains a GUID is used as identifier under which the refcount is stored. The components Comp1 and Comp2 are identical from the MSI perspective. After the installation of both MSIs the Component with the Id {100000….} has a refcount of two. After uninstallation of one MSI there is still a refcount of one which drops to zero just as expected when we uninstall the last msi. Then the file which was the same for both MSIs is deleted. You should remember that MSI keeps a refcount across MSIs for components with the same component id. MSI does manage components not the resources you did install. The resources associated with a component are then and only then deleted when the refcount of the component reaches zero.   The dependencies between features, components and resources can be described as relations. m,k are numbers >= 1, n can be 0. Inside a MSI the following relations are valid Feature    1  –> n Components Component    1 –> m Features Component      1  –>  k Resources These relations express that one feature can install several components and features can share components between them. Every (meaningful) component will install at least one resource which means that its name (primary key to stay in database speak) does occur in some other table in the Component column as value which installs some resource. Lets make it clear with an example. We want to install with the feature MainFeature some files a registry key and a shortcut. We can then create components Comp1..3 which are referenced by the resources defined in the corresponding tables.   Feature Component Registry File Shortcuts MainFeature Comp1 RegistryKey1     MainFeature Comp2   File.txt   MainFeature Comp3   File2.txt Shortcut to File2.txt   It is illegal that the same resource is part of more than one component since this would break the refcount mechanism. Lets illustrate this:            Feature ComponentId Resource Reference Count Feature1 {1000-…} File1.txt 1 Feature2 {2000-….} File1.txt 1 The installation part works well but what happens when you uninstall Feature2? Component {20000…} gets a refcount of zero where MSI deletes all resources belonging to this component. In this case File1.txt will be deleted. But Feature1 still has another component {10000…} with a refcount of one which means that the file was deleted too early. You just have ruined your installation. To fix it you then need to click on the Repair button under Add/Remove Programs to let MSI reinstall any missing registry keys, files or shortcuts. The vigilant reader might has noticed that there is more in the Component table. Beside its name and GUID it has also an installation directory, attributes and a KeyPath. The KeyPath is a reference to a file or registry key which is used to detect if the component is already installed. This becomes important when you repair or uninstall a component. To find out if the component is already installed MSI checks if the registry key or file referenced by the KeyPath property does exist. When it does not exist it assumes that it was either already uninstalled (can lead to problems during uninstall) or that it is already installed and all is fine. Why is this detail so important? Lets put all files into one component. The KeyPath should be then one of the files of your component to check if it was installed or not. When your installation becomes corrupt because a file was deleted you cannot repair it with the Repair button under Add/Remove Programs because MSI checks the component integrity via the Resource referenced by its KeyPath. As long as you did not delete the KeyPath file MSI thinks all resources with your component are installed and never executes any repair action. You get even more trouble when you try to remove files during an upgrade (you cannot remove files during an update) from your super component which contains all files. The only way out and therefore best practice is to assign for every resource you want to install an extra component. This ensures painless updatability and repairs and you have much less effort to remove specific files during an upgrade. In effect you get this best practice relation Feature 1  –> n Components Component   1  –>  1 Resources MSI Component Rules Rule 1 – One component per resource Every resource you want to install (file, registry key, value, environment value, shortcut, directory, …) must get its own component which does never change between versions as long as the install location is the same. Penalty If you add more than one resources to a component you will break the repair capability of MSI because the KeyPath is used to check if the component needs repair. MSI ComponentId Files MSI 1.0 {1000} File1-5 MSI 2.0 {2000} File2-5 You want to remove File1 in version 2.0 of your MSI. Since you want to keep the other files you create a new component and add them there. MSI will delete all files if the component refcount of {1000} drops to zero. The files you want to keep are added to the new component {2000}. Ok that does work if your upgrade does uninstall the old MSI first. This will cause the refcount of all previously installed components to reach zero which means that all files present in version 1.0 are deleted. But there is a faster way to perform your upgrade by first installing your new MSI and then remove the old one.  If you choose this upgrade path then you will loose File1-5 after your upgrade and not only File1 as intended by your new component design.   Rule 2 – Only add, never remove resources from a component If you did follow rule 1 you will not need Rule 2. You can add in a patch more resources to one component. That is ok. But you can never remove anything from it. There are tricky ways around that but I do not want to encourage bad component design. Penalty Lets assume you have 2 MSI files which install under the same component one file   MSI1 MSI2 {1000} - ComponentId {1000} – ComponentId File1.txt File2.txt   When you install and uninstall both MSIs you will end up with an installation where either File1 or File2 will be left. Why? It seems that MSI does not store the resources associated with each component in its internal database. Instead Windows will simply query the MSI that is currently uninstalled for all resources belonging to this component. Since it will find only one file and not two it will only uninstall one file. That is the main reason why you never can remove resources from a component!   Rule 3 Never Remove A Component From an Update MSI. This is the same as if you change the GUID of a component by accident for your new update package. The resulting update package will not contain all components from the previously installed package. Penalty When you remove a component from a feature MSI will set the feature state during update to Advertised and log a warning message into its log file when you did enable MSI logging. SELMGR: ComponentId '{2DCEA1BA-3E27-E222-484C-D0D66AEA4F62}' is registered to feature 'xxxxxxx, but is not present in the Component table.  Removal of components from a feature is not supported! MSI (c) (24:44) [07:53:13:436]: SELMGR: Removal of a component from a feature is not supported Advertised means that MSI treats all components of this feature as not installed. As a consequence during uninstall nothing will be removed since it is not installed! This is not only bad because uninstall does no longer work but this feature will also not get the required patches. All other features which have followed component versioning rules for update packages will be updated but the one faulty feature will not. This results in very hard to find bugs why an update was only partially successful. Things got better with Windows Installer 4.5 but you cannot rely on that nobody will use an older installer. It is a good idea to add to your update msiexec call MSIENFORCEUPGRADECOMPONENTRULES=1 which will abort the installation if you did violate this rule.

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• Ancillary Objects: Separate Debug ELF Files For Solaris

  - by Ali Bahrami

  We introduced a new object ELF object type in Solaris 11 Update 1 called the Ancillary Object. This posting describes them, using material originally written during their development, the PSARC arc case, and the Solaris Linker and Libraries Manual. ELF objects contain allocable sections, which are mapped into memory at runtime, and non-allocable sections, which are present in the file for use by debuggers and observability tools, but which are not mapped or used at runtime. Typically, all of these sections exist within a single object file. Ancillary objects allow them to instead go into a separate file. There are different reasons given for wanting such a feature. One can debate whether the added complexity is worth the benefit, and in most cases it is not. However, one important case stands out — customers with very large 32-bit objects who are not ready or able to make the transition to 64-bits. We have customers who build extremely large 32-bit objects. Historically, the debug sections in these objects have used the stabs format, which is limited, but relatively compact. In recent years, the industry has transitioned to the powerful but verbose DWARF standard. In some cases, the size of these debug sections is large enough to push the total object file size past the fundamental 4GB limit for 32-bit ELF object files. The best, and ultimately only, solution to overly large objects is to transition to 64-bits. However, consider environments where: Hundreds of users may be executing the code on large shared systems. (32-bits use less memory and bus bandwidth, and on sparc runs just as fast as 64-bit code otherwise). Complex finely tuned code, where the original authors may no longer be available. Critical production code, that was expensive to qualify and bring online, and which is otherwise serving its intended purpose without issue. Users in these risk adverse and/or high scale categories have good reasons to push 32-bits objects to the limit before moving on. Ancillary objects offer these users a longer runway. Design The design of ancillary objects is intended to be simple, both to help human understanding when examining elfdump output, and to lower the bar for debuggers such as dbx to support them. The primary and ancillary objects have the same set of section headers, with the same names, in the same order (i.e. each section has the same index in both files). A single added section of type SHT_SUNW_ANCILLARY is added to both objects, containing information that allows a debugger to identify and validate both files relative to each other. Given one of these files, the ancillary section allows you to identify the other. Allocable sections go in the primary object, and non-allocable ones go into the ancillary object. A small set of non-allocable objects, notably the symbol table, are copied into both objects. As noted above, most sections are only written to one of the two objects, but both objects have the same section header array. The section header in the file that does not contain the section data is tagged with the SHF_SUNW_ABSENT section header flag to indicate its placeholder status. Compiler writers and others who produce objects can set the SUNW_SHF_PRIMARY section header flag to mark non-allocable sections that should go to the primary object rather than the ancillary. If you don't request an ancillary object, the Solaris ELF format is unchanged. Users who don't use ancillary objects do not pay for the feature. This is important, because they exist to serve a small subset of our users, and must not complicate the common case. If you do request an ancillary object, the runtime behavior of the primary object will be the same as that of a normal object. There is no added runtime cost. The primary and ancillary object together represent a logical single object. This is facilitated by the use of a single set of section headers. One can easily imagine a tool that can merge a primary and ancillary object into a single file, or the reverse. (Note that although this is an interesting intellectual exercise, we don't actually supply such a tool because there's little practical benefit above and beyond using ld to create the files). Among the benefits of this approach are: There is no need for per-file symbol tables to reflect the contents of each file. The same symbol table that would be produced for a standard object can be used. The section contents are identical in either case — there is no need to alter data to accommodate multiple files. It is very easy for a debugger to adapt to these new files, and the processing involved can be encapsulated in input/output routines. Most of the existing debugger implementation applies without modification. The limit of a 4GB 32-bit output object is now raised to 4GB of code, and 4GB of debug data. There is also the future possibility (not currently supported) to support multiple ancillary objects, each of which could contain up to 4GB of additional debug data. It must be noted however that the 32-bit DWARF debug format is itself inherently 32-bit limited, as it uses 32-bit offsets between debug sections, so the ability to employ multiple ancillary object files may not turn out to be useful. Using Ancillary Objects (From the Solaris Linker and Libraries Guide) By default, objects contain both allocable and non-allocable sections. Allocable sections are the sections that contain executable code and the data needed by that code at runtime. Non-allocable sections contain supplemental information that is not required to execute an object at runtime. These sections support the operation of debuggers and other observability tools. The non-allocable sections in an object are not loaded into memory at runtime by the operating system, and so, they have no impact on memory use or other aspects of runtime performance no matter their size. For convenience, both allocable and non-allocable sections are normally maintained in the same file. However, there are situations in which it can be useful to separate these sections. To reduce the size of objects in order to improve the speed at which they can be copied across wide area networks. To support fine grained debugging of highly optimized code requires considerable debug data. In modern systems, the debugging data can easily be larger than the code it describes. The size of a 32-bit object is limited to 4 Gbytes. In very large 32-bit objects, the debug data can cause this limit to be exceeded and prevent the creation of the object. To limit the exposure of internal implementation details. Traditionally, objects have been stripped of non-allocable sections in order to address these issues. Stripping is effective, but destroys data that might be needed later. The Solaris link-editor can instead write non-allocable sections to an ancillary object. This feature is enabled with the -z ancillary command line option. $ ld ... -z ancillary[=outfile] ...By default, the ancillary file is given the same name as the primary output object, with a .anc file extension. However, a different name can be provided by providing an outfile value to the -z ancillary option. When -z ancillary is specified, the link-editor performs the following actions. All allocable sections are written to the primary object. In addition, all non-allocable sections containing one or more input sections that have the SHF_SUNW_PRIMARY section header flag set are written to the primary object. All remaining non-allocable sections are written to the ancillary object. The following non-allocable sections are written to both the primary object and ancillary object. .shstrtab The section name string table. .symtab The full non-dynamic symbol table. .symtab_shndx The symbol table extended index section associated with .symtab. .strtab The non-dynamic string table associated with .symtab. .SUNW_ancillary Contains the information required to identify the primary and ancillary objects, and to identify the object being examined. The primary object and all ancillary objects contain the same array of sections headers. Each section has the same section index in every file. Although the primary and ancillary objects all define the same section headers, the data for most sections will be written to a single file as described above. If the data for a section is not present in a given file, the SHF_SUNW_ABSENT section header flag is set, and the sh_size field is 0. This organization makes it possible to acquire a full list of section headers, a complete symbol table, and a complete list of the primary and ancillary objects from either of the primary or ancillary objects. The following example illustrates the underlying implementation of ancillary objects. An ancillary object is created by adding the -z ancillary command line option to an otherwise normal compilation. The file utility shows that the result is an executable named a.out, and an associated ancillary object named a.out.anc. $ cat hello.c #include <stdio.h> int main(int argc, char **argv) { (void) printf("hello, world\n"); return (0); } $ cc -g -zancillary hello.c $ file a.out a.out.anc a.out: ELF 32-bit LSB executable 80386 Version 1 [FPU], dynamically linked, not stripped, ancillary object a.out.anc a.out.anc: ELF 32-bit LSB ancillary 80386 Version 1, primary object a.out $ ./a.out hello worldThe resulting primary object is an ordinary executable that can be executed in the usual manner. It is no different at runtime than an executable built without the use of ancillary objects, and then stripped of non-allocable content using the strip or mcs commands. As previously described, the primary object and ancillary objects contain the same section headers. To see how this works, it is helpful to use the elfdump utility to display these section headers and compare them. The following table shows the section header information for a selection of headers from the previous link-edit example. Index Section Name Type Primary Flags Ancillary Flags Primary Size Ancillary Size 13 .text PROGBITS ALLOC EXECINSTR ALLOC EXECINSTR SUNW_ABSENT 0x131 0 20 .data PROGBITS WRITE ALLOC WRITE ALLOC SUNW_ABSENT 0x4c 0 21 .symtab SYMTAB 0 0 0x450 0x450 22 .strtab STRTAB STRINGS STRINGS 0x1ad 0x1ad 24 .debug_info PROGBITS SUNW_ABSENT 0 0 0x1a7 28 .shstrtab STRTAB STRINGS STRINGS 0x118 0x118 29 .SUNW_ancillary SUNW_ancillary 0 0 0x30 0x30 The data for most sections is only present in one of the two files, and absent from the other file. The SHF_SUNW_ABSENT section header flag is set when the data is absent. The data for allocable sections needed at runtime are found in the primary object. The data for non-allocable sections used for debugging but not needed at runtime are placed in the ancillary file. A small set of non-allocable sections are fully present in both files. These are the .SUNW_ancillary section used to relate the primary and ancillary objects together, the section name string table .shstrtab, as well as the symbol table.symtab, and its associated string table .strtab. It is possible to strip the symbol table from the primary object. A debugger that encounters an object without a symbol table can use the .SUNW_ancillary section to locate the ancillary object, and access the symbol contained within. The primary object, and all associated ancillary objects, contain a .SUNW_ancillary section that allows all the objects to be identified and related together. $ elfdump -T SUNW_ancillary a.out a.out.anc a.out: Ancillary Section: .SUNW_ancillary index tag value [0] ANC_SUNW_CHECKSUM 0x8724 [1] ANC_SUNW_MEMBER 0x1 a.out [2] ANC_SUNW_CHECKSUM 0x8724 [3] ANC_SUNW_MEMBER 0x1a3 a.out.anc [4] ANC_SUNW_CHECKSUM 0xfbe2 [5] ANC_SUNW_NULL 0 a.out.anc: Ancillary Section: .SUNW_ancillary index tag value [0] ANC_SUNW_CHECKSUM 0xfbe2 [1] ANC_SUNW_MEMBER 0x1 a.out [2] ANC_SUNW_CHECKSUM 0x8724 [3] ANC_SUNW_MEMBER 0x1a3 a.out.anc [4] ANC_SUNW_CHECKSUM 0xfbe2 [5] ANC_SUNW_NULL 0 The ancillary sections for both objects contain the same number of elements, and are identical except for the first element. Each object, starting with the primary object, is introduced with a MEMBER element that gives the file name, followed by a CHECKSUM that identifies the object. In this example, the primary object is a.out, and has a checksum of 0x8724. The ancillary object is a.out.anc, and has a checksum of 0xfbe2. The first element in a .SUNW_ancillary section, preceding the MEMBER element for the primary object, is always a CHECKSUM element, containing the checksum for the file being examined. The presence of a .SUNW_ancillary section in an object indicates that the object has associated ancillary objects. The names of the primary and all associated ancillary objects can be obtained from the ancillary section from any one of the files. It is possible to determine which file is being examined from the larger set of files by comparing the first checksum value to the checksum of each member that follows. Debugger Access and Use of Ancillary Objects Debuggers and other observability tools must merge the information found in the primary and ancillary object files in order to build a complete view of the object. This is equivalent to processing the information from a single file. This merging is simplified by the primary object and ancillary objects containing the same section headers, and a single symbol table. The following steps can be used by a debugger to assemble the information contained in these files. Starting with the primary object, or any of the ancillary objects, locate the .SUNW_ancillary section. The presence of this section identifies the object as part of an ancillary group, contains information that can be used to obtain a complete list of the files and determine which of those files is the one currently being examined. Create a section header array in memory, using the section header array from the object being examined as an initial template. Open and read each file identified by the .SUNW_ancillary section in turn. For each file, fill in the in-memory section header array with the information for each section that does not have the SHF_SUNW_ABSENT flag set. The result will be a complete in-memory copy of the section headers with pointers to the data for all sections. Once this information has been acquired, the debugger can proceed as it would in the single file case, to access and control the running program. Note - The ELF definition of ancillary objects provides for a single primary object, and an arbitrary number of ancillary objects. At this time, the Oracle Solaris link-editor only produces a single ancillary object containing all non-allocable sections. This may change in the future. Debuggers and other observability tools should be written to handle the general case of multiple ancillary objects. ELF Implementation Details (From the Solaris Linker and Libraries Guide) To implement ancillary objects, it was necessary to extend the ELF format to add a new object type (ET_SUNW_ANCILLARY), a new section type (SHT_SUNW_ANCILLARY), and 2 new section header flags (SHF_SUNW_ABSENT, SHF_SUNW_PRIMARY). In this section, I will detail these changes, in the form of diffs to the Solaris Linker and Libraries manual. Part IV ELF Application Binary Interface Chapter 13: Object File Format Object File Format Edit Note: This existing section at the beginning of the chapter describes the ELF header. There's a table of object file types, which now includes the new ET_SUNW_ANCILLARY type. e_type Identifies the object file type, as listed in the following table. NameValueMeaning ET_NONE0No file type ET_REL1Relocatable file ET_EXEC2Executable file ET_DYN3Shared object file ET_CORE4Core file ET_LOSUNW0xfefeStart operating system specific range ET_SUNW_ANCILLARY0xfefeAncillary object file ET_HISUNW0xfefdEnd operating system specific range ET_LOPROC0xff00Start processor-specific range ET_HIPROC0xffffEnd processor-specific range Sections Edit Note: This overview section defines the section header structure, and provides a high level description of known sections. It was updated to define the new SHF_SUNW_ABSENT and SHF_SUNW_PRIMARY flags and the new SHT_SUNW_ANCILLARY section. ... sh_type Categorizes the section's contents and semantics. Section types and their descriptions are listed in Table 13-5. sh_flags Sections support 1-bit flags that describe miscellaneous attributes. Flag definitions are listed in Table 13-8. ... Table 13-5 ELF Section Types, sh_type NameValue . . . SHT_LOSUNW0x6fffffee SHT_SUNW_ancillary0x6fffffee . . . ... SHT_LOSUNW - SHT_HISUNW Values in this inclusive range are reserved for Oracle Solaris OS semantics. SHT_SUNW_ANCILLARY Present when a given object is part of a group of ancillary objects. Contains information required to identify all the files that make up the group. See Ancillary Section. ... Table 13-8 ELF Section Attribute Flags NameValue . . . SHF_MASKOS0x0ff00000 SHF_SUNW_NODISCARD0x00100000 SHF_SUNW_ABSENT0x00200000 SHF_SUNW_PRIMARY0x00400000 SHF_MASKPROC0xf0000000 . . . ... SHF_SUNW_ABSENT Indicates that the data for this section is not present in this file. When ancillary objects are created, the primary object and any ancillary objects, will all have the same section header array, to facilitate merging them to form a complete view of the object, and to allow them to use the same symbol tables. Each file contains a subset of the section data. The data for allocable sections is written to the primary object while the data for non-allocable sections is written to an ancillary file. The SHF_SUNW_ABSENT flag is used to indicate that the data for the section is not present in the object being examined. When the SHF_SUNW_ABSENT flag is set, the sh_size field of the section header must be 0. An application encountering an SHF_SUNW_ABSENT section can choose to ignore the section, or to search for the section data within one of the related ancillary files. SHF_SUNW_PRIMARY The default behavior when ancillary objects are created is to write all allocable sections to the primary object and all non-allocable sections to the ancillary objects. The SHF_SUNW_PRIMARY flag overrides this behavior. Any output section containing one more input section with the SHF_SUNW_PRIMARY flag set is written to the primary object without regard for its allocable status. ... Two members in the section header, sh_link, and sh_info, hold special information, depending on section type. Table 13-9 ELF sh_link and sh_info Interpretation sh_typesh_linksh_info . . . SHT_SUNW_ANCILLARY The section header index of the associated string table. 0 . . . Special Sections Edit Note: This section describes the sections used in Solaris ELF objects, using the types defined in the previous description of section types. It was updated to define the new .SUNW_ancillary (SHT_SUNW_ANCILLARY) section. Various sections hold program and control information. Sections in the following table are used by the system and have the indicated types and attributes. Table 13-10 ELF Special Sections NameTypeAttribute . . . .SUNW_ancillarySHT_SUNW_ancillaryNone . . . ... .SUNW_ancillary Present when a given object is part of a group of ancillary objects. Contains information required to identify all the files that make up the group. See Ancillary Section for details. ... Ancillary Section Edit Note: This new section provides the format reference describing the layout of a .SUNW_ancillary section and the meaning of the various tags. Note that these sections use the same tag/value concept used for dynamic and capabilities sections, and will be familiar to anyone used to working with ELF. In addition to the primary output object, the Solaris link-editor can produce one or more ancillary objects. Ancillary objects contain non-allocable sections that would normally be written to the primary object. When ancillary objects are produced, the primary object and all of the associated ancillary objects contain a SHT_SUNW_ancillary section, containing information that identifies these related objects. Given any one object from such a group, the ancillary section provides the information needed to identify and interpret the others. This section contains an array of the following structures. See sys/elf.h. typedef struct { Elf32_Word a_tag; union { Elf32_Word a_val; Elf32_Addr a_ptr; } a_un; } Elf32_Ancillary; typedef struct { Elf64_Xword a_tag; union { Elf64_Xword a_val; Elf64_Addr a_ptr; } a_un; } Elf64_Ancillary; For each object with this type, a_tag controls the interpretation of a_un. a_val These objects represent integer values with various interpretations. a_ptr These objects represent file offsets or addresses. The following ancillary tags exist. Table 13-NEW1 ELF Ancillary Array Tags NameValuea_un ANC_SUNW_NULL0Ignored ANC_SUNW_CHECKSUM1a_val ANC_SUNW_MEMBER2a_ptr ANC_SUNW_NULL Marks the end of the ancillary section. ANC_SUNW_CHECKSUM Provides the checksum for a file in the c_val element. When ANC_SUNW_CHECKSUM precedes the first instance of ANC_SUNW_MEMBER, it provides the checksum for the object from which the ancillary section is being read. When it follows an ANC_SUNW_MEMBER tag, it provides the checksum for that member. ANC_SUNW_MEMBER Specifies an object name. The a_ptr element contains the string table offset of a null-terminated string, that provides the file name. An ancillary section must always contain an ANC_SUNW_CHECKSUM before the first instance of ANC_SUNW_MEMBER, identifying the current object. Following that, there should be an ANC_SUNW_MEMBER for each object that makes up the complete set of objects. Each ANC_SUNW_MEMBER should be followed by an ANC_SUNW_CHECKSUM for that object. A typical ancillary section will therefore be structured as: TagMeaning ANC_SUNW_CHECKSUMChecksum of this object ANC_SUNW_MEMBERName of object #1 ANC_SUNW_CHECKSUMChecksum for object #1 . . . ANC_SUNW_MEMBERName of object N ANC_SUNW_CHECKSUMChecksum for object N ANC_SUNW_NULL An object can therefore identify itself by comparing the initial ANC_SUNW_CHECKSUM to each of the ones that follow, until it finds a match. Related Other Work The GNU developers have also encountered the need/desire to support separate debug information files, and use the solution detailed at http://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html. At the current time, the separate debug file is constructed by building the standard object first, and then copying the debug data out of it in a separate post processing step, Hence, it is limited to a total of 4GB of code and debug data, just as a single object file would be. They are aware of this, and I have seen online comments indicating that they may add direct support for generating these separate files to their link-editor. It is worth noting that the GNU objcopy utility is available on Solaris, and that the Studio dbx debugger is able to use these GNU style separate debug files even on Solaris. Although this is interesting in terms giving Linux users a familiar environment on Solaris, the 4GB limit means it is not an answer to the problem of very large 32-bit objects. We have also encountered issues with objcopy not understanding Solaris-specific ELF sections, when using this approach. The GNU community also has a current effort to adapt their DWARF debug sections in order to move them to separate files before passing the relocatable objects to the linker. The details of Project Fission can be found at http://gcc.gnu.org/wiki/DebugFission. The goal of this project appears to be to reduce the amount of data seen by the link-editor. The primary effort revolves around moving DWARF data to separate .dwo files so that the link-editor never encounters them. The details of modifying the DWARF data to be usable in this form are involved — please see the above URL for details.

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• WLS MBeans

  - by Jani Rautiainen

  WLS provides a set of Managed Beans (MBeans) to configure, monitor and manage WLS resources. We can use the WLS MBeans to automate some of the tasks related to the configuration and maintenance of the WLS instance. The MBeans can be accessed a number of ways; using various UIs and programmatically using Java or WLST Python scripts.For customization development we can use the features to e.g. manage the deployed customization in MDS, control logging levels, automate deployment of dependent libraries etc. This article is an introduction on how to access and use the WLS MBeans. The goal is to illustrate the various access methods in a single article; the details of the features are left to the linked documentation.This article covers Windows based environment, steps for Linux would be similar however there would be some differences e.g. on how the file paths are defined. MBeansThe WLS MBeans can be categorized to runtime and configuration MBeans.The Runtime MBeans can be used to access the runtime information about the server and its resources. The data from runtime beans is only available while the server is running. The runtime beans can be used to e.g. check the state of the server or deployment.The Configuration MBeans contain information about the configuration of servers and resources. The configuration of the domain is stored in the config.xml file and the configuration MBeans can be used to access and modify the configuration data. For more information on the WLS MBeans refer to: Understanding WebLogic Server MBeans WLS MBean reference Java Management Extensions (JMX)We can use JMX APIs to access the WLS MBeans. This allows us to create Java programs to configure, monitor, and manage WLS resources. In order to use the WLS MBeans we need to add the following library into the class-path: WL_HOME\lib\wljmxclient.jar Connecting to a WLS MBean server The WLS MBeans are contained in a Mbean server, depending on the requirement we can connect to (MBean Server / JNDI Name): Domain Runtime MBean Server weblogic.management.mbeanservers.domainruntime Runtime MBean Server weblogic.management.mbeanservers.runtime Edit MBean Server weblogic.management.mbeanservers.edit To connect to the WLS MBean server first we need to create a map containing the credentials; Hashtable<String, String> param = new Hashtable<String, String>(); param.put(Context.SECURITY_PRINCIPAL, "weblogic");        param.put(Context.SECURITY_CREDENTIALS, "weblogic1");        param.put(JMXConnectorFactory.PROTOCOL_PROVIDER_PACKAGES, "weblogic.management.remote"); These define the user, password and package containing the protocol. Next we create the connection: JMXServiceURL serviceURL =     new JMXServiceURL("t3","127.0.0.1",7101,     "/jndi/weblogic.management.mbeanservers.domainruntime"); JMXConnector connector = JMXConnectorFactory.connect(serviceURL, param); MBeanServerConnection connection = connector.getMBeanServerConnection(); With the connection we can now access the MBeans for the WLS instance. For a complete example see Appendix A of this post. For more details refer to Accessing WebLogic Server MBeans with JMX Accessing WLS MBeans The WLS MBeans are structured hierarchically; in order to access content we need to know the path to the MBean we are interested in. The MBean is accessed using “MBeanServerConnection. getAttribute” API.  WLS provides entry points to the hierarchy allowing us to navigate all the WLS MBeans in the hierarchy (MBean Server / JMX object name): Domain Runtime MBean Server com.bea:Name=DomainRuntimeService,Type=weblogic.management.mbeanservers.domainruntime.DomainRuntimeServiceMBean Runtime MBean Servers com.bea:Name=RuntimeService,Type=weblogic.management.mbeanservers.runtime.RuntimeServiceMBean Edit MBean Server com.bea:Name=EditService,Type=weblogic.management.mbeanservers.edit.EditServiceMBean For example we can access the Domain Runtime MBean using: ObjectName service = new ObjectName( "com.bea:Name=DomainRuntimeService," + "Type=weblogic.management.mbeanservers.domainruntime.DomainRuntimeServiceMBean"); Same syntax works for any “child” WLS MBeans e.g. to find out all application deployments we can: ObjectName domainConfig = (ObjectName)connection.getAttribute(service,"DomainConfiguration"); ObjectName[] appDeployments = (ObjectName[])connection.getAttribute(domainConfig,"AppDeployments"); Alternatively we could access the same MBean using the full syntax: ObjectName domainConfig = new ObjectName("com.bea:Location=DefaultDomain,Name=DefaultDomain,Type=Domain"); ObjectName[] appDeployments = (ObjectName[])connection.getAttribute(domainConfig,"AppDeployments"); For more details refer to Accessing WebLogic Server MBeans with JMX Invoking operations on WLS MBeans The WLS MBean operations can be invoked with MBeanServerConnection. invoke API; in the following example we query the state of “AppsLoggerService” application: ObjectName appRuntimeStateRuntime = new ObjectName("com.bea:Name=AppRuntimeStateRuntime,Type=AppRuntimeStateRuntime"); Object[] parameters = { "AppsLoggerService", "DefaultServer" }; String[] signature = { "java.lang.String", "java.lang.String" }; String result = (String)connection.invoke(appRuntimeStateRuntime,"getCurrentState",parameters, signature); The result returned should be "STATE_ACTIVE" assuming the "AppsLoggerService" application is up and running. WebLogic Scripting Tool (WLST) The WebLogic Scripting Tool (WLST) is a command-line scripting environment that we can access the same WLS MBeans. The tool is located under: $MW_HOME\oracle_common\common\bin\wlst.bat Do note that there are several instances of the wlst script under the $MW_HOME, each of them works, however the commands available vary, so we want to use the one under “oracle_common”. The tool is started in offline mode. In offline mode we can access and manipulate the domain configuration. In online mode we can access the runtime information. We connect to the Administration Server : connect("weblogic","weblogic1", "t3://127.0.0.1:7101") In both online and offline modes we can navigate the WLS MBean using commands like "ls" to print content and "cd" to navigate between objects, for example: All the commands available can be obtained with: help('all') For details of the tool refer to WebLogic Scripting Tool and for the commands available WLST Command and Variable Reference. Also do note that the WLST tool can be invoked from Java code in Embedded Mode. Running Scripts The WLST tool allows us to automate tasks using Python scripts in Script Mode. The script can be manually created or recorded by the WLST tool. Example commands of recording a script: startRecording("c:/temp/recording.py") <commands that we want to record> stopRecording() We can run the script from WLST: execfile("c:/temp/recording.py") We can also run the script from the command line: C:\apps\Oracle\Middleware\oracle_common\common\bin\wlst.cmd c:/temp/recording.py There are various sample scripts are provided with the WLS instance. UI to Access the WLS MBeans There are various UIs through which we can access the WLS MBeans. Oracle Enterprise Manager Fusion Middleware Control Oracle WebLogic Server Administration Console Fusion Middleware Control MBean Browser In the integrated JDeveloper environment only the Oracle WebLogic Server Administration Console is available to us. For more information refer to the documentation, one noteworthy feature in the console is the ability to record WLST scripts based on the navigation. In addition to the UIs above the JConsole included in the JDK can be used to access the WLS MBeans. The JConsole needs to be started with specific parameter to force WLS objects to be used and jar files in the classpath: "C:\apps\Oracle\Middleware\jdk160_24\bin\jconsole" -J-Djava.class.path=C:\apps\Oracle\Middleware\jdk160_24\lib\jconsole.jar;C:\apps\Oracle\Middleware\jdk160_24\lib\tools.jar;C:\apps\Oracle\Middleware\wlserver_10.3\server\lib\wljmxclient.jar -J-Djmx.remote.protocol.provider.pkgs=weblogic.management.remote For more details refer to the Accessing Custom MBeans from JConsole. Summary In this article we have covered various ways we can access and use the WLS MBeans in context of integrated WLS in JDeveloper to be used for Fusion Application customization development. References Developing Custom Management Utilities With JMX for Oracle WebLogic Server Accessing WebLogic Server MBeans with JMX WebLogic Server MBean Reference WebLogic Scripting Tool WLST Command and Variable Reference Appendix A package oracle.apps.test; import java.io.IOException;import java.net.MalformedURLException;import java.util.Hashtable;import javax.management.MBeanServerConnection;import javax.management.MalformedObjectNameException;import javax.management.ObjectName;import javax.management.remote.JMXConnector;import javax.management.remote.JMXConnectorFactory;import javax.management.remote.JMXServiceURL;import javax.naming.Context;/** * This class contains simple examples on how to access WLS MBeans using JMX. */public class BlogExample {    /**     * Connection to the WLS MBeans     */    private MBeanServerConnection connection;    /**     * Constructor that takes in the connection information for the      * domain and obtains the resources from WLS MBeans using JMX.     * @param hostName host name to connect to for the WLS server     * @param port port to connect to for the WLS server     * @param userName user name to connect to for the WLS server     * @param password password to connect to for the WLS server     */    public BlogExample(String hostName, String port, String userName,                       String password) {        super();        try {            initConnection(hostName, port, userName, password);        } catch (Exception e) {            throw new RuntimeException("Unable to connect to the domain " +                                       hostName + ":" + port);        }    }    /**     * Default constructor.     * Tries to create connection with default values. Runtime exception will be     * thrown if the default values are not used in the local instance.     */    public BlogExample() {        this("127.0.0.1", "7101", "weblogic", "weblogic1");    }    /**     * Initializes the JMX connection to the WLS Beans     * @param hostName host name to connect to for the WLS server     * @param port port to connect to for the WLS server     * @param userName user name to connect to for the WLS server     * @param password password to connect to for the WLS server     * @throws IOException error connecting to the WLS MBeans     * @throws MalformedURLException error connecting to the WLS MBeans     * @throws MalformedObjectNameException error connecting to the WLS MBeans     */    private void initConnection(String hostName, String port, String userName,                                String password)                                 throws IOException, MalformedURLException,                                        MalformedObjectNameException {        String protocol = "t3";        String jndiroot = "/jndi/";        String mserver = "weblogic.management.mbeanservers.domainruntime";        JMXServiceURL serviceURL =            new JMXServiceURL(protocol, hostName, Integer.valueOf(port),                              jndiroot + mserver);        Hashtable<String, String> h = new Hashtable<String, String>();        h.put(Context.SECURITY_PRINCIPAL, userName);        h.put(Context.SECURITY_CREDENTIALS, password);        h.put(JMXConnectorFactory.PROTOCOL_PROVIDER_PACKAGES,              "weblogic.management.remote");        JMXConnector connector = JMXConnectorFactory.connect(serviceURL, h);        connection = connector.getMBeanServerConnection();    }    /**     * Main method used to invoke the logic for testing     * @param args arguments passed to the program     */    public static void main(String[] args) {        BlogExample blogExample = new BlogExample();        blogExample.testEntryPoint();        blogExample.testDirectAccess();        blogExample.testInvokeOperation();    }    /**     * Example of using an entry point to navigate the WLS MBean hierarchy.     */    public void testEntryPoint() {        try {            System.out.println("testEntryPoint");            ObjectName service =             new ObjectName("com.bea:Name=DomainRuntimeService,Type=" +"weblogic.management.mbeanservers.domainruntime.DomainRuntimeServiceMBean");            ObjectName domainConfig =                (ObjectName)connection.getAttribute(service,                                                    "DomainConfiguration");            ObjectName[] appDeployments =                (ObjectName[])connection.getAttribute(domainConfig,                                                      "AppDeployments");            for (ObjectName appDeployment : appDeployments) {                String resourceIdentifier =                    (String)connection.getAttribute(appDeployment,                                                    "SourcePath");                System.out.println(resourceIdentifier);            }        } catch (Exception e) {            throw new RuntimeException(e);        }    }    /**     * Example of accessing WLS MBean directly with a full reference.     * This does the same thing as testEntryPoint in slightly difference way.     */    public void testDirectAccess() {        try {            System.out.println("testDirectAccess");            ObjectName appDeployment =                new ObjectName("com.bea:Location=DefaultDomain,"+                               "Name=AppsLoggerService,Type=AppDeployment");            String resourceIdentifier =                (String)connection.getAttribute(appDeployment, "SourcePath");            System.out.println(resourceIdentifier);        } catch (Exception e) {            throw new RuntimeException(e);        }    }    /**     * Example of invoking operation on a WLS MBean.     */    public void testInvokeOperation() {        try {            System.out.println("testInvokeOperation");            ObjectName appRuntimeStateRuntime =                new ObjectName("com.bea:Name=AppRuntimeStateRuntime,"+                               "Type=AppRuntimeStateRuntime");            String identifier = "AppsLoggerService";            String serverName = "DefaultServer";            Object[] parameters = { identifier, serverName };            String[] signature = { "java.lang.String", "java.lang.String" };            String result =                (String)connection.invoke(appRuntimeStateRuntime, "getCurrentState",                                          parameters, signature);            System.out.println("State of " + identifier + " = " + result);        } catch (Exception e) {            throw new RuntimeException(e);        }    }}

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• ASP.NET Frameworks and Raw Throughput Performance

  - by Rick Strahl

  A few days ago I had a curious thought: With all these different technologies that the ASP.NET stack has to offer, what's the most efficient technology overall to return data for a server request? When I started this it was mere curiosity rather than a real practical need or result. Different tools are used for different problems and so performance differences are to be expected. But still I was curious to see how the various technologies performed relative to each just for raw throughput of the request getting to the endpoint and back out to the client with as little processing in the actual endpoint logic as possible (aka Hello World!). I want to clarify that this is merely an informal test for my own curiosity and I'm sharing the results and process here because I thought it was interesting. It's been a long while since I've done any sort of perf testing on ASP.NET, mainly because I've not had extremely heavy load requirements and because overall ASP.NET performs very well even for fairly high loads so that often it's not that critical to test load performance. This post is not meant to make a point  or even come to a conclusion which tech is better, but just to act as a reference to help understand some of the differences in perf and give a starting point to play around with this yourself. I've included the code for this simple project, so you can play with it and maybe add a few additional tests for different things if you like. Source Code on GitHub I looked at this data for these technologies: ASP.NET Web API ASP.NET MVC WebForms ASP.NET WebPages ASMX AJAX Services  (couldn't get AJAX/JSON to run on IIS8 ) WCF Rest Raw ASP.NET HttpHandlers It's quite a mixed bag, of course and the technologies target different types of development. What started out as mere curiosity turned into a bit of a head scratcher as the results were sometimes surprising. What I describe here is more to satisfy my curiosity more than anything and I thought it interesting enough to discuss on the blog :-) First test: Raw Throughput The first thing I did is test raw throughput for the various technologies. This is the least practical test of course since you're unlikely to ever create the equivalent of a 'Hello World' request in a real life application. The idea here is to measure how much time a 'NOP' request takes to return data to the client. So for this request I create the simplest Hello World request that I could come up for each tech. Http Handler The first is the lowest level approach which is an HTTP handler. public class Handler : IHttpHandler { public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/plain"; context.Response.Write("Hello World. Time is: " + DateTime.Now.ToString()); } public bool IsReusable { get { return true; } } } WebForms Next I added a couple of ASPX pages - one using CodeBehind and one using only a markup page. The CodeBehind page simple does this in CodeBehind without any markup in the ASPX page: public partial class HelloWorld_CodeBehind : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { Response.Write("Hello World. Time is: " + DateTime.Now.ToString() ); Response.End(); } } while the Markup page only contains some static output via an expression:<%@ Page Language="C#" AutoEventWireup="false" CodeBehind="HelloWorld_Markup.aspx.cs" Inherits="AspNetFrameworksPerformance.HelloWorld_Markup" %> Hello World. Time is <%= DateTime.Now %> ASP.NET WebPages WebPages is the freestanding Razor implementation of ASP.NET. Here's the simple HelloWorld.cshtml page:Hello World @DateTime.Now WCF REST WCF REST was the token REST implementation for ASP.NET before WebAPI and the inbetween step from ASP.NET AJAX. I'd like to forget that this technology was ever considered for production use, but I'll include it here. Here's an OperationContract class: [ServiceContract(Namespace = "")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class WcfService { [OperationContract] [WebGet] public Stream HelloWorld() { var data = Encoding.Unicode.GetBytes("Hello World" + DateTime.Now.ToString()); var ms = new MemoryStream(data); // Add your operation implementation here return ms; } } WCF REST can return arbitrary results by returning a Stream object and a content type. The code above turns the string result into a stream and returns that back to the client. ASP.NET AJAX (ASMX Services) I also wanted to test ASP.NET AJAX services because prior to WebAPI this is probably still the most widely used AJAX technology for the ASP.NET stack today. Unfortunately I was completely unable to get this running on my Windows 8 machine. Visual Studio 2012  removed adding of ASP.NET AJAX services, and when I tried to manually add the service and configure the script handler references it simply did not work - I always got a SOAP response for GET and POST operations. No matter what I tried I always ended up getting XML results even when explicitly adding the ScriptHandler. So, I didn't test this (but the code is there - you might be able to test this on a Windows 7 box). ASP.NET MVC Next up is probably the most popular ASP.NET technology at the moment: MVC. Here's the small controller: public class MvcPerformanceController : Controller { public ActionResult Index() { return View(); } public ActionResult HelloWorldCode() { return new ContentResult() { Content = "Hello World. Time is: " + DateTime.Now.ToString() }; } } ASP.NET WebAPI Next up is WebAPI which looks kind of similar to MVC. Except here I have to use a StringContent result to return the response: public class WebApiPerformanceController : ApiController { [HttpGet] public HttpResponseMessage HelloWorldCode() { return new HttpResponseMessage() { Content = new StringContent("Hello World. Time is: " + DateTime.Now.ToString(), Encoding.UTF8, "text/plain") }; } } Testing Take a minute to think about each of the technologies… and take a guess which you think is most efficient in raw throughput. The fastest should be pretty obvious, but the others - maybe not so much. The testing I did is pretty informal since it was mainly to satisfy my curiosity - here's how I did this: I used Apache Bench (ab.exe) from a full Apache HTTP installation to run and log the test results of hitting the server. ab.exe is a small executable that lets you hit a URL repeatedly and provides counter information about the number of requests, requests per second etc. ab.exe and the batch file are located in the \LoadTests folder of the project. An ab.exe command line  looks like this: ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorld which hits the specified URL 100,000 times with a load factor of 20 concurrent requests. This results in output like this:   It's a great way to get a quick and dirty performance summary. Run it a few times to make sure there's not a large amount of varience. You might also want to do an IISRESET to clear the Web Server. Just make sure you do a short test run to warm up the server first - otherwise your first run is likely to be skewed downwards. ab.exe also allows you to specify headers and provide POST data and many other things if you want to get a little more fancy. Here all tests are GET requests to keep it simple. I ran each test: 100,000 iterations Load factor of 20 concurrent connections IISReset before starting A short warm up run for API and MVC to make sure startup cost is mitigated Here is the batch file I used for the test: IISRESET REM make sure you add REM C:\Program Files (x86)\Apache Software Foundation\Apache2.2\bin REM to your path so ab.exe can be found REM Warm up ab.exe -n100 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldJsonab.exe -n100 -c20 http://localhost/aspnetperf/api/HelloWorldJson ab.exe -n100 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorld ab.exe -n100000 -c20 http://localhost/aspnetperf/handler.ashx > handler.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/HelloWorld_CodeBehind.aspx > AspxCodeBehind.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/HelloWorld_Markup.aspx > AspxMarkup.txt ab.exe -n100000 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorld > Wcf.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldCode > Mvc.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorld > WebApi.txt I ran each of these tests 3 times and took the average score for Requests/second, with the machine otherwise idle. I did see a bit of variance when running many tests but the values used here are the medians. Part of this has to do with the fact I ran the tests on my local machine - result would probably more consistent running the load test on a separate machine hitting across the network. I ran these tests locally on my laptop which is a Dell XPS with quad core Sandibridge I7-2720QM @ 2.20ghz and a fast SSD drive on Windows 8. CPU load during tests ran to about 70% max across all 4 cores (IOW, it wasn't overloading the machine). Ideally you can try running these tests on a separate machine hitting the local machine. If I remember correctly IIS 7 and 8 on client OSs don't throttle so the performance here should be Results Ok, let's cut straight to the chase. Below are the results from the tests… It's not surprising that the handler was fastest. But it was a bit surprising to me that the next fastest was WebForms and especially Web Forms with markup over a CodeBehind page. WebPages also fared fairly well. MVC and WebAPI are a little slower and the slowest by far is WCF REST (which again I find surprising). As mentioned at the start the raw throughput tests are not overly practical as they don't test scripting performance for the HTML generation engines or serialization performances of the data engines. All it really does is give you an idea of the raw throughput for the technology from time of request to reaching the endpoint and returning minimal text data back to the client which indicates full round trip performance. But it's still interesting to see that Web Forms performs better in throughput than either MVC, WebAPI or WebPages. It'd be interesting to try this with a few pages that actually have some parsing logic on it, but that's beyond the scope of this throughput test. But what's also amazing about this test is the sheer amount of traffic that a laptop computer is handling. Even the slowest tech managed 5700 requests a second, which is one hell of a lot of requests if you extrapolate that out over a 24 hour period. Remember these are not static pages, but dynamic requests that are being served. Another test - JSON Data Service Results The second test I used a JSON result from several of the technologies. I didn't bother running WebForms and WebPages through this test since that doesn't make a ton of sense to return data from the them (OTOH, returning text from the APIs didn't make a ton of sense either :-) In these tests I have a small Person class that gets serialized and then returned to the client. The Person class looks like this: public class Person { public Person() { Id = 10; Name = "Rick"; Entered = DateTime.Now; } public int Id { get; set; } public string Name { get; set; } public DateTime Entered { get; set; } } Here are the updated handler classes that use Person: Handler public class Handler : IHttpHandler { public void ProcessRequest(HttpContext context) { var action = context.Request.QueryString["action"]; if (action == "json") JsonRequest(context); else TextRequest(context); } public void TextRequest(HttpContext context) { context.Response.ContentType = "text/plain"; context.Response.Write("Hello World. Time is: " + DateTime.Now.ToString()); } public void JsonRequest(HttpContext context) { var json = JsonConvert.SerializeObject(new Person(), Formatting.None); context.Response.ContentType = "application/json"; context.Response.Write(json); } public bool IsReusable { get { return true; } } } This code adds a little logic to check for a action query string and route the request to an optional JSON result method. To generate JSON, I'm using the same JSON.NET serializer (JsonConvert.SerializeObject) used in Web API to create the JSON response. WCF REST   [ServiceContract(Namespace = "")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class WcfService { [OperationContract] [WebGet] public Stream HelloWorld() { var data = Encoding.Unicode.GetBytes("Hello World " + DateTime.Now.ToString()); var ms = new MemoryStream(data); // Add your operation implementation here return ms; } [OperationContract] [WebGet(ResponseFormat=WebMessageFormat.Json,BodyStyle=WebMessageBodyStyle.WrappedRequest)] public Person HelloWorldJson() { // Add your operation implementation here return new Person(); } } For WCF REST all I have to do is add a method with the Person result type.   ASP.NET MVC public class MvcPerformanceController : Controller { // // GET: /MvcPerformance/ public ActionResult Index() { return View(); } public ActionResult HelloWorldCode() { return new ContentResult() { Content = "Hello World. Time is: " + DateTime.Now.ToString() }; } public JsonResult HelloWorldJson() { return Json(new Person(), JsonRequestBehavior.AllowGet); } } For MVC all I have to do for a JSON response is return a JSON result. ASP.NET internally uses JavaScriptSerializer. ASP.NET WebAPI public class WebApiPerformanceController : ApiController { [HttpGet] public HttpResponseMessage HelloWorldCode() { return new HttpResponseMessage() { Content = new StringContent("Hello World. Time is: " + DateTime.Now.ToString(), Encoding.UTF8, "text/plain") }; } [HttpGet] public Person HelloWorldJson() { return new Person(); } [HttpGet] public HttpResponseMessage HelloWorldJson2() { var response = new HttpResponseMessage(HttpStatusCode.OK); response.Content = new ObjectContent<Person>(new Person(), GlobalConfiguration.Configuration.Formatters.JsonFormatter); return response; } } Testing and Results To run these data requests I used the following ab.exe commands:REM JSON RESPONSES ab.exe -n100000 -c20 http://localhost/aspnetperf/Handler.ashx?action=json > HandlerJson.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/MvcPerformance/HelloWorldJson > MvcJson.txt ab.exe -n100000 -c20 http://localhost/aspnetperf/api/HelloWorldJson > WebApiJson.txt ab.exe -n100000 -c20 http://localhost/AspNetPerf/WcfService.svc/HelloWorldJson > WcfJson.txt The results from this test run are a bit interesting in that the WebAPI test improved performance significantly over returning plain string content. Here are the results:   The performance for each technology drops a little bit except for WebAPI which is up quite a bit! From this test it appears that WebAPI is actually significantly better performing returning a JSON response, rather than a plain string response. Snag with Apache Benchmark and 'Length Failures' I ran into a little snag with Apache Benchmark, which was reporting failures for my Web API requests when serializing. As the graph shows performance improved significantly from with JSON results from 5580 to 6530 or so which is a 15% improvement (while all others slowed down by 3-8%). However, I was skeptical at first because the WebAPI test reports showed a bunch of errors on about 10% of the requests. Check out this report: Notice the Failed Request count. What the hey? Is WebAPI failing on roughly 10% of requests when sending JSON? Turns out: No it's not! But it took some sleuthing to figure out why it reports these failures. At first I thought that Web API was failing, and so to make sure I re-ran the test with Fiddler attached and runiisning the ab.exe test by using the -X switch: ab.exe -n100 -c10 -X localhost:8888 http://localhost/aspnetperf/api/HelloWorldJson which showed that indeed all requests where returning proper HTTP 200 results with full content. However ab.exe was reporting the errors. After some closer inspection it turned out that the dates varying in size altered the response length in dynamic output. For example: these two results: {"Id":10,"Name":"Rick","Entered":"2012-09-04T10:57:24.841926-10:00"} {"Id":10,"Name":"Rick","Entered":"2012-09-04T10:57:24.8519262-10:00"} are different in length for the number which results in 68 and 69 bytes respectively. The same URL produces different result lengths which is what ab.exe reports. I didn't notice at first bit the same is happening when running the ASHX handler with JSON.NET result since it uses the same serializer that varies the milliseconds. Moral: You can typically ignore Length failures in Apache Benchmark and when in doubt check the actual output with Fiddler. Note that the other failure values are accurate though. Another interesting Side Note: Perf drops over Time As I was running these tests repeatedly I was finding that performance steadily dropped from a startup peak to a 10-15% lower stable level. IOW, with Web API I'd start out with around 6500 req/sec and in subsequent runs it keeps dropping until it would stabalize somewhere around 5900 req/sec occasionally jumping lower. For these tests this is why I did the IIS RESET and warm up for individual tests. This is a little puzzling. Looking at Process Monitor while the test are running memory very quickly levels out as do handles and threads, on the first test run. Subsequent runs everything stays stable, but the performance starts going downwards. This applies to all the technologies - Handlers, Web Forms, MVC, Web API - curious to see if others test this and see similar results. Doing an IISRESET then resets everything and performance starts off at peak again… Summary As I stated at the outset, these were informal to satiate my curiosity not to prove that any technology is better or even faster than another. While there clearly are differences in performance the differences (other than WCF REST which was by far the slowest and the raw handler which was by far the highest) are relatively minor, so there is no need to feel that any one technology is a runaway standout in raw performance. Choosing a technology is about more than pure performance but also about the adequateness for the job and the easy of implementation. The strengths of each technology will make for any minor performance difference we see in these tests. However, to me it's important to get an occasional reality check and compare where new technologies are heading. Often times old stuff that's been optimized and designed for a time of less horse power can utterly blow the doors off newer tech and simple checks like this let you compare. Luckily we're seeing that much of the new stuff performs well even in V1.0 which is great. To me it was very interesting to see Web API perform relatively badly with plain string content, which originally led me to think that Web API might not be properly optimized just yet. For those that caught my Tweets late last week regarding WebAPI's slow responses was with String content which is in fact considerably slower. Luckily where it counts with serialized JSON and XML WebAPI actually performs better. But I do wonder what would make generic string content slower than serialized code? This stresses another point: Don't take a single test as the final gospel and don't extrapolate out from a single set of tests. Certainly Twitter can make you feel like a fool when you post something immediate that hasn't been fleshed out a little more <blush>. Egg on my face. As a result I ended up screwing around with this for a few hours today to compare different scenarios. Well worth the time… I hope you found this useful, if not for the results, maybe for the process of quickly testing a few requests for performance and charting out a comparison. Now onwards with more serious stuff… Resources Source Code on GitHub Apache HTTP Server Project (ab.exe is part of the binary distribution)© Rick Strahl, West Wind Technologies, 2005-2012Posted in ASP.NET  Web Api   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• ANTS CLR and Memory Profiler In Depth Review (Part 1 of 2 &ndash; CLR Profiler)

  - by ToStringTheory

  One of the things that people might not know about me, is my obsession to make my code as efficient as possible.  Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind…  In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve.  One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well.  In this review, I am going to cover some of the features of the ANTS profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program.  I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction The ANTS Profiler pack provided by Red Gate was something that I had not heard of before receiving an email regarding an offer to review it for a license.  Since I look to make my code efficient, it was a no brainer for me to try it out!  One thing that I have to say took me by surprise is that upon downloading the program and installing it you fill out a form for your usual contact information.  Sure enough within 2 hours, I received an email from a sales representative at Red Gate asking if she could help me to achieve the most out of my trial time so it wouldn’t go to waste.  After replying to her and explaining that I was looking to review its feature set, she put me in contact with someone that setup a demo session to give me a quick rundown of its features via an online meeting.  After having dealt with a massive ordeal with one of my utility companies and their complete lack of customer service, Red Gates friendly and helpful representatives were a breath of fresh air, and something I was thankful for. ANTS CLR Profiler The ANTS CLR profiler is the thing I want to focus on the most in this post, so I am going to dive right in now. Install was simple and took no time at all.  It installed both the profiler for the CLR and Memory, but also visual studio extensions to facilitate the usage of the profilers (click any images for full size images): The Visual Studio menu options (under ANTS menu) Starting the CLR Performance Profiler from the start menu yields this window If you follow the instructions after launching the program from the start menu (Click File > New Profiling Session to start a new project), you are given a dialog with plenty of options for profiling: The New Session dialog.  Lots of options.  One thing I noticed is that the buttons in the lower right were half-covered by the panel of the application.  If I had to guess, I would imagine that this is caused by my DPI settings being set to 125%.  This is a problem I have seen in other applications as well that don’t scale well to different dpi scales. The profiler options give you the ability to profile: .NET Executable ASP.NET web application (hosted in IIS) ASP.NET web application (hosted in IIS express) ASP.NET web application (hosted in Cassini Web Development Server) SharePoint web application (hosted in IIS) Silverlight 4+ application Windows Service COM+ server XBAP (local XAML browser application) Attach to an already running .NET 4 process Choosing each option provides a varying set of other variables/options that one can set including options such as application arguments, operating path, record I/O performance performance counters to record (43 counters in all!), etc…  All in all, they give you the ability to profile many different .Net project types, and make it simple to do so.  In most cases of my using this application, I would be using the built in Visual Studio extensions, as they automatically start a new profiling project in ANTS with the options setup, and start your program, however RedGate has made it easy enough to profile outside of Visual Studio as well. On the flip side of this, as someone who lives most of their work life in Visual Studio, one thing I do wish is that instead of opening an entirely separate application/gui to perform profiling after launching, that instead they would provide a Visual Studio panel with the information, and integrate more of the profiling project information into Visual Studio.  So, now that we have an idea of what options that the profiler gives us, its time to test its abilities and features. Horrendous Example Code – Prime Number Generator One of my interests besides development, is Physics and Math – what I went to college for.  I have especially always been interested in prime numbers, as they are something of a mystery…  So, I decided that I would go ahead and to test the abilities of the profiler, I would write a small program, website, and library to generate prime numbers in the quantity that you ask for.  I am going to start off with some terrible code, and show how I would see the profiler being used as a development tool. First off, the IPrimes interface (all code is downloadable at the end of the post): interface IPrimes { IEnumerable<int> GetPrimes(int retrieve); } Simple enough, right?  Anything that implements the interface will (hopefully) provide an IEnumerable of int, with the quantity specified in the parameter argument.  Next, I am going to implement this interface in the most basic way: public class DumbPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _analyzing = 4; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; //start dividing at 2 //divide until number is reached, or determined not prime for (int i = 2; i < _analyzing && isPrime; i++) { //if (i) goes into _analyzing without a remainder, //_analyzing is NOT prime if (_analyzing % i == 0) isPrime = false; } //if it is prime, add to found list if (isPrime) _foundPrimes.Add(_analyzing); //increment number to analyze next _analyzing++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } This is the simplest way to get primes in my opinion.  Checking each number by the straight definition of a prime – is it divisible by anything besides 1 and itself. I have included this code in a base class library for my solution, as I am going to use it to demonstrate a couple of features of ANTS.  This class library is consumed by a simple non-MVVM WPF application, and a simple MVC4 website.  I will not post the WPF code here inline, as it is simply an ObservableCollection<int>, a label, two textbox’s, and a button. Starting a new Profiling Session So, in Visual Studio, I have just completed my first stint developing the GUI and DumbPrimes IPrimes class, so now I want to check my codes efficiency by profiling it.  All I have to do is build the solution (surprised initiating a profiling session doesn’t do this, but I suppose I can understand it), and then click the ANTS menu, followed by Profile Performance.  I am then greeted by the profiler starting up and already monitoring my program live: You are provided with a realtime graph at the top, and a pane at the bottom giving you information on how to proceed.  I am going to start by asking my program to show me the first 15000 primes: After the program finally began responding again (I did all the work on the main UI thread – how bad!), I stopped the profiler, which did kill the process of my program too.  One important thing to note, is that the profiler by default wants to give you a lot of detail about the operation – line hit counts, time per line, percent time per line, etc…  The important thing to remember is that this itself takes a lot of time.  When running my program without the profiler attached, it can generate the 15000 primes in 5.18 seconds, compared to 74.5 seconds – almost a 1500 percent increase.  While this may seem like a lot, remember that there is a trade off.  It may be WAY more inefficient, however, I am able to drill down and make improvements to specific problem areas, and then decrease execution time all around. Analyzing the Profiling Session After clicking ‘Stop Profiling’, the process running my application stopped, and the entire execution time was automatically selected by ANTS, and the results shown below: Now there are a number of interesting things going on here, I am going to cover each in a section of its own: Real Time Performance Counter Bar (top of screen) At the top of the screen, is the real time performance bar.  As your application is running, this will constantly update with the currently selected performance counters status.  A couple of cool things to note are the fact that you can drag a selection around specific time periods to drill down the detail views in the lower 2 panels to information pertaining to only that period. After selecting a time period, you can bookmark a section and name it, so that it is easy to find later, or after reloaded at a later time.  You can also zoom in, out, or fit the graph to the space provided – useful for drilling down. It may be hard to see, but at the top of the processor time graph below the time ticks, but above the red usage graph, there is a green bar. This bar shows at what times a method that is selected in the ‘Call tree’ panel is called. Very cool to be able to click on a method and see at what times it made an impact. As I said before, ANTS provides 43 different performance counters you can hook into.  Click the arrow next to the Performance tab at the top will allow you to change between different counters if you have them selected: Method Call Tree, ADO.Net Database Calls, File IO – Detail Panel Red Gate really hit the mark here I think. When you select a section of the run with the graph, the call tree populates to fill a hierarchical tree of method calls, with information regarding each of the methods.   By default, methods are hidden where the source is not provided (framework type code), however, Red Gate has integrated Reflector into ANTS, so even if you don’t have source for something, you can select a method and get the source if you want.  Methods are also hidden where the impact is seen as insignificant – methods that are only executed for 1% of the time of the overall calling methods time; in other words, working on making them better is not where your efforts should be focused. – Smart! Source Panel – Detail Panel The source panel is where you can see line level information on your code, showing the code for the currently selected method from the Method Call Tree.  If the code is not available, Reflector takes care of it and shows the code anyways! As you can notice, there does seem to be a problem with how ANTS determines what line is the actual line that a call is completed on.  I have suspicions that this may be due to some of the inline code optimizations that the CLR applies upon compilation of the assembly.  In a method with comments, the problem is much more severe: As you can see here, apparently the most offending code in my base library was a comment – *gasp*!  Removing the comments does help quite a bit, however I hope that Red Gate works on their counter algorithm soon to improve the logic on positioning for statistics: I did a small test just to demonstrate the lines are correct without comments. For me, it isn’t a deal breaker, as I can usually determine the correct placements by looking at the application code in the region and determining what makes sense, but it is something that would probably build up some irritation with time. Feature – Suggest Method for Optimization A neat feature to really help those in need of a pointer, is the menu option under tools to automatically suggest methods to optimize/improve: Nice feature – clicking it filters the call tree and stars methods that it thinks are good candidates for optimization.  I do wish that they would have made it more visible for those of use who aren’t great on sight: Process Integration I do think that this could have a place in my process.  After experimenting with the profiler, I do think it would be a great benefit to do some development, testing, and then after all the bugs are worked out, use the profiler to check on things to make sure nothing seems like it is hogging more than its fair share.  For example, with this program, I would have developed it, ran it, tested it – it works, but slowly. After looking at the profiler, and seeing the massive amount of time spent in 1 method, I might go ahead and try to re-implement IPrimes (I actually would probably rewrite the offending code, but so that I can distribute both sets of code easily, I’m just going to make another implementation of IPrimes).  Using two pieces of knowledge about prime numbers can make this method MUCH more efficient – prime numbers fall into two buckets 6k+/-1 , and a number is prime if it is not divisible by any other primes before it: public class SmartPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _k = 1; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; int potentialPrime; //analyze 6k-1 //assign the value to potential potentialPrime = 6 * _k - 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); if (_foundPrimes.Count() == retrieve) break; //analyze 6k+1 //assign the value to potential potentialPrime = 6 * _k + 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); //increment k to analyze next _k++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } Now there are definitely more things I can do to help make this more efficient, but for the scope of this example, I think this is fine (but still hideous)! Profiling this now yields a happy surprise 27 seconds to generate the 15000 primes with the profiler attached, and only 1.43 seconds without.  One important thing I wanted to call out though was the performance graph now: Notice anything odd?  The %Processor time is above 100%.  This is because there is now more than 1 core in the operation.  A better label for the chart in my mind would have been %Core time, but to each their own. Another odd thing I noticed was that the profiler seemed to be spot on this time in my DumbPrimes class with line details in source, even with comments..  Odd. Profiling Web Applications The last thing that I wanted to cover, that means a lot to me as a web developer, is the great amount of work that Red Gate put into the profiler when profiling web applications.  In my solution, I have a simple MVC4 application setup with 1 page, a single input form, that will output prime values as my WPF app did.  Launching the profiler from Visual Studio as before, nothing is really different in the profiler window, however I did receive a UAC prompt for a Red Gate helper app to integrate with the web server without notification. After requesting 500, 1000, 2000, and 5000 primes, and looking at the profiler session, things are slightly different from before: As you can see, there are 4 spikes of activity in the processor time graph, but there is also something new in the call tree: That’s right – ANTS will actually group method calls by get/post operations, so it is easier to find out what action/page is giving the largest problems…  Pretty cool in my mind! Overview Overall, I think that Red Gate ANTS CLR Profiler has a lot to offer, however I think it also has a long ways to go.  3 Biggest Pros: Ability to easily drill down from time graph, to method calls, to source code Wide variety of counters to choose from when profiling your application Excellent integration/grouping of methods being called from web applications by request – BRILLIANT! 3 Biggest Cons: Issue regarding line details in source view Nit pick – Processor time vs. Core time Nit pick – Lack of full integration with Visual Studio Ratings Ease of Use (7/10) – I marked down here because of the problems with the line level details and the extra work that that entails, and the lack of better integration with Visual Studio. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Especially with its large variety of performance counters, a definite plus! Features (9/10) – Besides the real time performance monitoring, and the drill downs that I’ve shown here, ANTS also has great integration with ADO.Net, with the ability to show database queries run by your application in the profiler.  This, with the line level details, the web request grouping, reflector integration, and various options to customize your profiling session I think create a great set of features! Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (8/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (8/10) – Overall, I am happy with the Performance Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  I WOULD recommend you trying the application and seeing if it would fit into your process, BUT, remember there are still some kinks in it to hopefully be worked out. My next post will definitely be shorter (hopefully), but thank you for reading up to here, or skipping ahead!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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• Much Ado About Nothing: Stub Objects

  - by user9154181

  The Solaris 11 link-editor (ld) contains support for a new type of object that we call a stub object. A stub object is a shared object, built entirely from mapfiles, that supplies the same linking interface as the real object, while containing no code or data. Stub objects cannot be executed — the runtime linker will kill any process that attempts to load one. However, you can link to a stub object as a dependency, allowing the stub to act as a proxy for the real version of the object. You may well wonder if there is a point to producing an object that contains nothing but linking interface. As it turns out, stub objects are very useful for building large bodies of code such as Solaris. In the last year, we've had considerable success in applying them to one of our oldest and thorniest build problems. In this discussion, I will describe how we came to invent these objects, and how we apply them to building Solaris. This posting explains where the idea for stub objects came from, and details our long and twisty journey from hallway idea to standard link-editor feature. I expect that these details are mainly of interest to those who work on Solaris and its makefiles, those who have done so in the past, and those who work with other similar bodies of code. A subsequent posting will omit the history and background details, and instead discuss how to build and use stub objects. If you are mainly interested in what stub objects are, and don't care about the underlying software war stories, I encourage you to skip ahead. The Long Road To Stubs This all started for me with an email discussion in May of 2008, regarding a change request that was filed in 2002, entitled: 4631488 lib/Makefile is too patient: .WAITs should be reduced This CR encapsulates a number of cronic issues with Solaris builds: We build Solaris with a parallel make (dmake) that tries to build as much of the code base in parallel as possible. There is a lot of code to build, and we've long made use of parallelized builds to get the job done quicker. This is even more important in today's world of massively multicore hardware. Solaris contains a large number of executables and shared objects. Executables depend on shared objects, and shared objects can depend on each other. Before you can build an object, you need to ensure that the objects it needs have been built. This implies a need for serialization, which is in direct opposition to the desire to build everying in parallel. To accurately build objects in the right order requires an accurate set of make rules defining the things that depend on each other. This sounds simple, but the reality is quite complex. In practice, having programmers explicitly specify these dependencies is a losing strategy: It's really hard to get right. It's really easy to get it wrong and never know it because things build anyway. Even if you get it right, it won't stay that way, because dependencies between objects can change over time, and make cannot help you detect such drifing. You won't know that you got it wrong until the builds break. That can be a long time after the change that triggered the breakage happened, making it hard to connect the cause and the effect. Usually this happens just before a release, when the pressure is on, its hard to think calmly, and there is no time for deep fixes. As a poor compromise, the libraries in core Solaris were built using a set of grossly incomplete hand written rules, supplemented with a number of dmake .WAIT directives used to group the libraries into sets of non-interacting groups that can be built in parallel because we think they don't depend on each other. From time to time, someone will suggest that we could analyze the built objects themselves to determine their dependencies and then generate make rules based on those relationships. This is possible, but but there are complications that limit the usefulness of that approach: To analyze an object, you have to build it first. This is a classic chicken and egg scenario. You could analyze the results of a previous build, but then you're not necessarily going to get accurate rules for the current code. It should be possible to build the code without having a built workspace available. The analysis will take time, and remember that we're constantly trying to make builds faster, not slower. By definition, such an approach will always be approximate, and therefore only incremantally more accurate than the hand written rules described above. The hand written rules are fast and cheap, while this idea is slow and complex, so we stayed with the hand written approach. Solaris was built that way, essentially forever, because these are genuinely difficult problems that had no easy answer. The makefiles were full of build races in which the right outcomes happened reliably for years until a new machine or a change in build server workload upset the accidental balance of things. After figuring out what had happened, you'd mutter "How did that ever work?", add another incomplete and soon to be inaccurate make dependency rule to the system, and move on. This was not a satisfying solution, as we tend to be perfectionists in the Solaris group, but we didn't have a better answer. It worked well enough, approximately. And so it went for years. We needed a different approach — a new idea to cut the Gordian Knot. In that discussion from May 2008, my fellow linker-alien Rod Evans had the initial spark that lead us to a game changing series of realizations: The link-editor is used to link objects together, but it only uses the ELF metadata in the object, consisting of symbol tables, ELF versioning sections, and similar data. Notably, it does not look at, or understand, the machine code that makes an object useful at runtime. If you had an object that only contained the ELF metadata for a dependency, but not the code or data, the link-editor would find it equally useful for linking, and would never know the difference. Call it a stub object. In the core Solaris OS, we require all objects to be built with a link-editor mapfile that describes all of its publically available functions and data. Could we build a stub object using the mapfile for the real object? It ought to be very fast to build stub objects, as there are no input objects to process. Unlike the real object, stub objects would not actually require any dependencies, and so, all of the stubs for the entire system could be built in parallel. When building the real objects, one could link against the stub objects instead of the real dependencies. This means that all the real objects can be built built in parallel too, without any serialization. We could replace a system that requires perfect makefile rules with a system that requires no ordering rules whatsoever. The results would be considerably more robust. We immediately realized that this idea had potential, but also that there were many details to sort out, lots of work to do, and that perhaps it wouldn't really pan out. As is often the case, it would be necessary to do the work and see how it turned out. Following that conversation, I set about trying to build a stub object. We determined that a faithful stub has to do the following: Present the same set of global symbols, with the same ELF versioning, as the real object. Functions are simple — it suffices to have a symbol of the right type, possibly, but not necessarily, referencing a null function in its text segment. Copy relocations make data more complicated to stub. The possibility of a copy relocation means that when you create a stub, the data symbols must have the actual size of the real data. Any error in this will go uncaught at link time, and will cause tragic failures at runtime that are very hard to diagnose. For reasons too obscure to go into here, involving tentative symbols, it is also important that the data reside in bss, or not, matching its placement in the real object. If the real object has more than one symbol pointing at the same data item, we call these aliased symbols. All data symbols in the stub object must exhibit the same aliasing as the real object. We imagined the stub library feature working as follows: A command line option to ld tells it to produce a stub rather than a real object. In this mode, only mapfiles are examined, and any object or shared libraries on the command line are are ignored. The extra information needed (function or data, size, and bss details) would be added to the mapfile. When building the real object instead of the stub, the extra information for building stubs would be validated against the resulting object to ensure that they match. In exploring these ideas, I immediately run headfirst into the reality of the original mapfile syntax, a subject that I would later write about as The Problem(s) With Solaris SVR4 Link-Editor Mapfiles. The idea of extending that poor language was a non-starter. Until a better mapfile syntax became available, which seemed unlikely in 2008, the solution could not involve extentions to the mapfile syntax. Instead, we cooked up the idea (hack) of augmenting mapfiles with stylized comments that would carry the necessary information. A typical definition might look like: # DATA(i386) __iob 0x3c0 # DATA(amd64,sparcv9) __iob 0xa00 # DATA(sparc) __iob 0x140 iob; A further problem then became clear: If we can't extend the mapfile syntax, then there's no good way to extend ld with an option to produce stub objects, and to validate them against the real objects. The idea of having ld read comments in a mapfile and parse them for content is an unacceptable hack. The entire point of comments is that they are strictly for the human reader, and explicitly ignored by the tool. Taking all of these speed bumps into account, I made a new plan: A perl script reads the mapfiles, generates some small C glue code to produce empty functions and data definitions, compiles and links the stub object from the generated glue code, and then deletes the generated glue code. Another perl script used after both objects have been built, to compare the real and stub objects, using data from elfdump, and validate that they present the same linking interface. By June 2008, I had written the above, and generated a stub object for libc. It was a useful prototype process to go through, and it allowed me to explore the ideas at a deep level. Ultimately though, the result was unsatisfactory as a basis for real product. There were so many issues: The use of stylized comments were fine for a prototype, but not close to professional enough for shipping product. The idea of having to document and support it was a large concern. The ideal solution for stub objects really does involve having the link-editor accept the same arguments used to build the real object, augmented with a single extra command line option. Any other solution, such as our prototype script, will require makefiles to be modified in deeper ways to support building stubs, and so, will raise barriers to converting existing code. A validation script that rederives what the linker knew when it built an object will always be at a disadvantage relative to the actual linker that did the work. A stub object should be identifyable as such. In the prototype, there was no tag or other metadata that would let you know that they weren't real objects. Being able to identify a stub object in this way means that the file command can tell you what it is, and that the runtime linker can refuse to try and run a program that loads one. At that point, we needed to apply this prototype to building Solaris. As you might imagine, the task of modifying all the makefiles in the core Solaris code base in order to do this is a massive task, and not something you'd enter into lightly. The quality of the prototype just wasn't good enough to justify that sort of time commitment, so I tabled the project, putting it on my list of long term things to think about, and moved on to other work. It would sit there for a couple of years. Semi-coincidentally, one of the projects I tacked after that was to create a new mapfile syntax for the Solaris link-editor. We had wanted to do something about the old mapfile syntax for many years. Others before me had done some paper designs, and a great deal of thought had already gone into the features it should, and should not have, but for various reasons things had never moved beyond the idea stage. When I joined Sun in late 2005, I got involved in reviewing those things and thinking about the problem. Now in 2008, fresh from relearning for the Nth time why the old mapfile syntax was a huge impediment to linker progress, it seemed like the right time to tackle the mapfile issue. Paving the way for proper stub object support was not the driving force behind that effort, but I certainly had them in mind as I moved forward. The new mapfile syntax, which we call version 2, integrated into Nevada build snv_135 in in February 2010: 6916788 ld version 2 mapfile syntax PSARC/2009/688 Human readable and extensible ld mapfile syntax In order to prove that the new mapfile syntax was adequate for general purpose use, I had also done an overhaul of the ON consolidation to convert all mapfiles to use the new syntax, and put checks in place that would ensure that no use of the old syntax would creep back in. That work went back into snv_144 in June 2010: 6916796 OSnet mapfiles should use version 2 link-editor syntax That was a big putback, modifying 517 files, adding 18 new files, and removing 110 old ones. I would have done this putback anyway, as the work was already done, and the benefits of human readable syntax are obvious. However, among the justifications listed in CR 6916796 was this We anticipate adding additional features to the new mapfile language that will be applicable to ON, and which will require all sharable object mapfiles to use the new syntax. I never explained what those additional features were, and no one asked. It was premature to say so, but this was a reference to stub objects. By that point, I had already put together a working prototype link-editor with the necessary support for stub objects. I was pleased to find that building stubs was indeed very fast. On my desktop system (Ultra 24), an amd64 stub for libc can can be built in a fraction of a second: % ptime ld -64 -z stub -o stubs/libc.so.1 -G -hlibc.so.1 \ -ztext -zdefs -Bdirect ... real 0.019708910 user 0.010101680 sys 0.008528431 In order to go from prototype to integrated link-editor feature, I knew that I would need to prove that stub objects were valuable. And to do that, I knew that I'd have to switch the Solaris ON consolidation to use stub objects and evaluate the outcome. And in order to do that experiment, ON would first need to be converted to version 2 mapfiles. Sub-mission accomplished. Normally when you design a new feature, you can devise reasonably small tests to show it works, and then deploy it incrementally, letting it prove its value as it goes. The entire point of stub objects however was to demonstrate that they could be successfully applied to an extremely large and complex code base, and specifically to solve the Solaris build issues detailed above. There was no way to finesse the matter — in order to move ahead, I would have to successfully use stub objects to build the entire ON consolidation and demonstrate their value. In software, the need to boil the ocean can often be a warning sign that things are trending in the wrong direction. Conversely, sometimes progress demands that you build something large and new all at once. A big win, or a big loss — sometimes all you can do is try it and see what happens. And so, I spent some time staring at ON makefiles trying to get a handle on how things work, and how they'd have to change. It's a big and messy world, full of complex interactions, unspecified dependencies, special cases, and knowledge of arcane makefile features... ...and so, I backed away, put it down for a few months and did other work... ...until the fall, when I felt like it was time to stop thinking and pondering (some would say stalling) and get on with it. Without stubs, the following gives a simplified high level view of how Solaris is built: An initially empty directory known as the proto, and referenced via the ROOT makefile macro is established to receive the files that make up the Solaris distribution. A top level setup rule creates the proto area, and performs operations needed to initialize the workspace so that the main build operations can be launched, such as copying needed header files into the proto area. Parallel builds are launched to build the kernel (usr/src/uts), libraries (usr/src/lib), and commands. The install makefile target builds each item and delivers a copy to the proto area. All libraries and executables link against the objects previously installed in the proto, implying the need to synchronize the order in which things are built. Subsequent passes run lint, and do packaging. Given this structure, the additions to use stub objects are: A new second proto area is established, known as the stub proto and referenced via the STUBROOT makefile macro. The stub proto has the same structure as the real proto, but is used to hold stub objects. All files in the real proto are delivered as part of the Solaris product. In contrast, the stub proto is used to build the product, and then thrown away. A new target is added to library Makefiles called stub. This rule builds the stub objects. The ld command is designed so that you can build a stub object using the same ld command line you'd use to build the real object, with the addition of a single -z stub option. This means that the makefile rules for building the stub objects are very similar to those used to build the real objects, and many existing makefile definitions can be shared between them. A new target is added to the Makefiles called stubinstall which delivers the stub objects built by the stub rule into the stub proto. These rules reuse much of existing plumbing used by the existing install rule. The setup rule runs stubinstall over the entire lib subtree as part of its initialization. All libraries and executables link against the objects in the stub proto rather than the main proto, and can therefore be built in parallel without any synchronization. There was no small way to try this that would yield meaningful results. I would have to take a leap of faith and edit approximately 1850 makefiles and 300 mapfiles first, trusting that it would all work out. Once the editing was done, I'd type make and see what happened. This took about 6 weeks to do, and there were many dark days when I'd question the entire project, or struggle to understand some of the many twisted and complex situations I'd uncover in the makefiles. I even found a couple of new issues that required changes to the new stub object related code I'd added to ld. With a substantial amount of encouragement and help from some key people in the Solaris group, I eventually got the editing done and stub objects for the entire workspace built. I found that my desktop system could build all the stub objects in the workspace in roughly a minute. This was great news, as it meant that use of the feature is effectively free — no one was likely to notice or care about the cost of building them. After another week of typing make, fixing whatever failed, and doing it again, I succeeded in getting a complete build! The next step was to remove all of the make rules and .WAIT statements dedicated to controlling the order in which libraries under usr/src/lib are built. This came together pretty quickly, and after a few more speed bumps, I had a workspace that built cleanly and looked like something you might actually be able to integrate someday. This was a significant milestone, but there was still much left to do. I turned to doing full nightly builds. Every type of build (open, closed, OpenSolaris, export, domestic) had to be tried. Each type failed in a new and unique way, requiring some thinking and rework. As things came together, I became aware of things that could have been done better, simpler, or cleaner, and those things also required some rethinking, the seeking of wisdom from others, and some rework. After another couple of weeks, it was in close to final form. My focus turned towards the end game and integration. This was a huge workspace, and needed to go back soon, before changes in the gate would made merging increasingly difficult. At this point, I knew that the stub objects had greatly simplified the makefile logic and uncovered a number of race conditions, some of which had been there for years. I assumed that the builds were faster too, so I did some builds intended to quantify the speedup in build time that resulted from this approach. It had never occurred to me that there might not be one. And so, I was very surprised to find that the wall clock build times for a stock ON workspace were essentially identical to the times for my stub library enabled version! This is why it is important to always measure, and not just to assume. One can tell from first principles, based on all those removed dependency rules in the library makefile, that the stub object version of ON gives dmake considerably more opportunities to overlap library construction. Some hypothesis were proposed, and shot down: Could we have disabled dmakes parallel feature? No, a quick check showed things being build in parallel. It was suggested that we might be I/O bound, and so, the threads would be mostly idle. That's a plausible explanation, but system stats didn't really support it. Plus, the timing between the stub and non-stub cases were just too suspiciously identical. Are our machines already handling as much parallelism as they are capable of, and unable to exploit these additional opportunities? Once again, we didn't see the evidence to back this up. Eventually, a more plausible and obvious reason emerged: We build the libraries and commands (usr/src/lib, usr/src/cmd) in parallel with the kernel (usr/src/uts). The kernel is the long leg in that race, and so, wall clock measurements of build time are essentially showing how long it takes to build uts. Although it would have been nice to post a huge speedup immediately, we can take solace in knowing that stub objects simplify the makefiles and reduce the possibility of race conditions. The next step in reducing build time should be to find ways to reduce or overlap the uts part of the builds. When that leg of the build becomes shorter, then the increased parallelism in the libs and commands will pay additional dividends. Until then, we'll just have to settle for simpler and more robust. And so, I integrated the link-editor support for creating stub objects into snv_153 (November 2010) with 6993877 ld should produce stub objects PSARC/2010/397 ELF Stub Objects followed by the work to convert the ON consolidation in snv_161 (February 2011) with 7009826 OSnet should use stub objects 4631488 lib/Makefile is too patient: .WAITs should be reduced This was a huge putback, with 2108 modified files, 8 new files, and 2 removed files. Due to the size, I was allowed a window after snv_160 closed in which to do the putback. It went pretty smoothly for something this big, a few more preexisting race conditions would be discovered and addressed over the next few weeks, and things have been quiet since then. Conclusions and Looking Forward Solaris has been built with stub objects since February. The fact that developers no longer specify the order in which libraries are built has been a big success, and we've eliminated an entire class of build error. That's not to say that there are no build races left in the ON makefiles, but we've taken a substantial bite out of the problem while generally simplifying and improving things. The introduction of a stub proto area has also opened some interesting new possibilities for other build improvements. As this article has become quite long, and as those uses do not involve stub objects, I will defer that discussion to a future article.

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• Using TPL and PLINQ to raise performance of feed aggregator

  - by DigiMortal

  In this posting I will show you how to use Task Parallel Library (TPL) and PLINQ features to boost performance of simple RSS-feed aggregator. I will use here only very basic .NET classes that almost every developer starts from when learning parallel programming. Of course, we will also measure how every optimization affects performance of feed aggregator. Feed aggregator Our feed aggregator works as follows: Load list of blogs Download RSS-feed Parse feed XML Add new posts to database Our feed aggregator is run by task scheduler after every 15 minutes by example. We will start our journey with serial implementation of feed aggregator. Second step is to use task parallelism and parallelize feeds downloading and parsing. And our last step is to use data parallelism to parallelize database operations. We will use Stopwatch class to measure how much time it takes for aggregator to download and insert all posts from all registered blogs. After every run we empty posts table in database. Serial aggregation Before doing parallel stuff let’s take a look at serial implementation of feed aggregator. All tasks happen one after other. internal class FeedClient {     private readonly INewsService _newsService;     private const int FeedItemContentMaxLength = 255;       public FeedClient()     {          ObjectFactory.Initialize(container =>          {              container.PullConfigurationFromAppConfig = true;          });           _newsService = ObjectFactory.GetInstance<INewsService>();     }       public void Execute()     {         var blogs = _newsService.ListPublishedBlogs();           for (var index = 0; index <blogs.Count; index++)         {              ImportFeed(blogs[index]);         }     }       private void ImportFeed(BlogDto blog)     {         if(blog == null)             return;         if (string.IsNullOrEmpty(blog.RssUrl))             return;           var uri = new Uri(blog.RssUrl);         SyndicationContentFormat feedFormat;           feedFormat = SyndicationDiscoveryUtility.SyndicationContentFormatGet(uri);           if (feedFormat == SyndicationContentFormat.Rss)             ImportRssFeed(blog);         if (feedFormat == SyndicationContentFormat.Atom)             ImportAtomFeed(blog);                 }       private void ImportRssFeed(BlogDto blog)     {         var uri = new Uri(blog.RssUrl);         var feed = RssFeed.Create(uri);           foreach (var item in feed.Channel.Items)         {             SaveRssFeedItem(item, blog.Id, blog.CreatedById);         }     }       private void ImportAtomFeed(BlogDto blog)     {         var uri = new Uri(blog.RssUrl);         var feed = AtomFeed.Create(uri);           foreach (var item in feed.Entries)         {             SaveAtomFeedEntry(item, blog.Id, blog.CreatedById);         }     } } Serial implementation of feed aggregator downloads and inserts all posts with 25.46 seconds. Task parallelism Task parallelism means that separate tasks are run in parallel. You can find out more about task parallelism from MSDN page Task Parallelism (Task Parallel Library) and Wikipedia page Task parallelism. Although finding parts of code that can run safely in parallel without synchronization issues is not easy task we are lucky this time. Feeds import and parsing is perfect candidate for parallel tasks. We can safely parallelize feeds import because importing tasks doesn’t share any resources and therefore they don’t also need any synchronization. After getting the list of blogs we iterate through the collection and start new TPL task for each blog feed aggregation. internal class FeedClient {     private readonly INewsService _newsService;     private const int FeedItemContentMaxLength = 255;       public FeedClient()     {          ObjectFactory.Initialize(container =>          {              container.PullConfigurationFromAppConfig = true;          });           _newsService = ObjectFactory.GetInstance<INewsService>();     }       public void Execute()     {         var blogs = _newsService.ListPublishedBlogs();                var tasks = new Task[blogs.Count];           for (var index = 0; index <blogs.Count; index++)         {             tasks[index] = new Task(ImportFeed, blogs[index]);             tasks[index].Start();         }           Task.WaitAll(tasks);     }       private void ImportFeed(object blogObject)     {         if(blogObject == null)             return;         var blog = (BlogDto)blogObject;         if (string.IsNullOrEmpty(blog.RssUrl))             return;           var uri = new Uri(blog.RssUrl);         SyndicationContentFormat feedFormat;           feedFormat = SyndicationDiscoveryUtility.SyndicationContentFormatGet(uri);           if (feedFormat == SyndicationContentFormat.Rss)             ImportRssFeed(blog);         if (feedFormat == SyndicationContentFormat.Atom)             ImportAtomFeed(blog);                }       private void ImportRssFeed(BlogDto blog)     {          var uri = new Uri(blog.RssUrl);          var feed = RssFeed.Create(uri);           foreach (var item in feed.Channel.Items)          {              SaveRssFeedItem(item, blog.Id, blog.CreatedById);          }     }     private void ImportAtomFeed(BlogDto blog)     {         var uri = new Uri(blog.RssUrl);         var feed = AtomFeed.Create(uri);           foreach (var item in feed.Entries)         {             SaveAtomFeedEntry(item, blog.Id, blog.CreatedById);         }     } } You should notice first signs of the power of TPL. We made only minor changes to our code to parallelize blog feeds aggregating. On my machine this modification gives some performance boost – time is now 17.57 seconds. Data parallelism There is one more way how to parallelize activities. Previous section introduced task or operation based parallelism, this section introduces data based parallelism. By MSDN page Data Parallelism (Task Parallel Library) data parallelism refers to scenario in which the same operation is performed concurrently on elements in a source collection or array. In our code we have independent collections we can process in parallel – imported feed entries. As checking for feed entry existence and inserting it if it is missing from database doesn’t affect other entries the imported feed entries collection is ideal candidate for parallelization. internal class FeedClient {     private readonly INewsService _newsService;     private const int FeedItemContentMaxLength = 255;       public FeedClient()     {          ObjectFactory.Initialize(container =>          {              container.PullConfigurationFromAppConfig = true;          });           _newsService = ObjectFactory.GetInstance<INewsService>();     }       public void Execute()     {         var blogs = _newsService.ListPublishedBlogs();                var tasks = new Task[blogs.Count];           for (var index = 0; index <blogs.Count; index++)         {             tasks[index] = new Task(ImportFeed, blogs[index]);             tasks[index].Start();         }           Task.WaitAll(tasks);     }       private void ImportFeed(object blogObject)     {         if(blogObject == null)             return;         var blog = (BlogDto)blogObject;         if (string.IsNullOrEmpty(blog.RssUrl))             return;           var uri = new Uri(blog.RssUrl);         SyndicationContentFormat feedFormat;           feedFormat = SyndicationDiscoveryUtility.SyndicationContentFormatGet(uri);           if (feedFormat == SyndicationContentFormat.Rss)             ImportRssFeed(blog);         if (feedFormat == SyndicationContentFormat.Atom)             ImportAtomFeed(blog);                }       private void ImportRssFeed(BlogDto blog)     {         var uri = new Uri(blog.RssUrl);         var feed = RssFeed.Create(uri);           feed.Channel.Items.AsParallel().ForAll(a =>         {             SaveRssFeedItem(a, blog.Id, blog.CreatedById);         });      }        private void ImportAtomFeed(BlogDto blog)      {         var uri = new Uri(blog.RssUrl);         var feed = AtomFeed.Create(uri);           feed.Entries.AsParallel().ForAll(a =>         {              SaveAtomFeedEntry(a, blog.Id, blog.CreatedById);         });      } } We did small change again and as the result we parallelized checking and saving of feed items. This change was data centric as we applied same operation to all elements in collection. On my machine I got better performance again. Time is now 11.22 seconds. Results Let’s visualize our measurement results (numbers are given in seconds). As we can see then with task parallelism feed aggregation takes about 25% less time than in original case. When adding data parallelism to task parallelism our aggregation takes about 2.3 times less time than in original case. More about TPL and PLINQ Adding parallelism to your application can be very challenging task. You have to carefully find out parts of your code where you can safely go to parallel processing and even then you have to measure the effects of parallel processing to find out if parallel code performs better. If you are not careful then troubles you will face later are worse than ones you have seen before (imagine error that occurs by average only once per 10000 code runs). Parallel programming is something that is hard to ignore. Effective programs are able to use multiple cores of processors. Using TPL you can also set degree of parallelism so your application doesn’t use all computing cores and leaves one or more of them free for host system and other processes. And there are many more things in TPL that make it easier for you to start and go on with parallel programming. In next major version all .NET languages will have built-in support for parallel programming. There will be also new language constructs that support parallel programming. Currently you can download Visual Studio Async to get some idea about what is coming. Conclusion Parallel programming is very challenging but good tools offered by Visual Studio and .NET Framework make it way easier for us. In this posting we started with feed aggregator that imports feed items on serial mode. With two steps we parallelized feed importing and entries inserting gaining 2.3 times raise in performance. Although this number is specific to my test environment it shows clearly that parallel programming may raise the performance of your application significantly.

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• Using Stub Objects

  - by user9154181

  Having told the long and winding tale of where stub objects came from and how we use them to build Solaris, I'd like to focus now on the the nuts and bolts of building and using them. The following new features were added to the Solaris link-editor (ld) to support the production and use of stub objects: -z stub This new command line option informs ld that it is to build a stub object rather than a normal object. In this mode, it accepts the same command line arguments as usual, but will quietly ignore any objects and sharable object dependencies. STUB_OBJECT Mapfile Directive In order to build a stub version of an object, its mapfile must specify the STUB_OBJECT directive. When producing a non-stub object, the presence of STUB_OBJECT causes the link-editor to perform extra validation to ensure that the stub and non-stub objects will be compatible. ASSERT Mapfile Directive All data symbols exported from the object must have an ASSERT symbol directive in the mapfile that declares them as data and supplies the size, binding, bss attributes, and symbol aliasing details. When building the stub objects, the information in these ASSERT directives is used to create the data symbols. When building the real object, these ASSERT directives will ensure that the real object matches the linking interface presented by the stub. Although ASSERT was added to the link-editor in order to support stub objects, they are a general purpose feature that can be used independently of stub objects. For instance you might choose to use an ASSERT directive if you have a symbol that must have a specific address in order for the object to operate properly and you want to automatically ensure that this will always be the case. The material presented here is derived from a document I originally wrote during the development effort, which had the dual goals of providing supplemental materials for the stub object PSARC case, and as a set of edits that were eventually applied to the Oracle Solaris Linker and Libraries Manual (LLM). The Solaris 11 LLM contains this information in a more polished form. Stub Objects A stub object is a shared object, built entirely from mapfiles, that supplies the same linking interface as the real object, while containing no code or data. Stub objects cannot be used at runtime. However, an application can be built against a stub object, where the stub object provides the real object name to be used at runtime, and then use the real object at runtime. When building a stub object, the link-editor ignores any object or library files specified on the command line, and these files need not exist in order to build a stub. Since the compilation step can be omitted, and because the link-editor has relatively little work to do, stub objects can be built very quickly. Stub objects can be used to solve a variety of build problems: Speed Modern machines, using a version of make with the ability to parallelize operations, are capable of compiling and linking many objects simultaneously, and doing so offers significant speedups. However, it is typical that a given object will depend on other objects, and that there will be a core set of objects that nearly everything else depends on. It is necessary to impose an ordering that builds each object before any other object that requires it. This ordering creates bottlenecks that reduce the amount of parallelization that is possible and limits the overall speed at which the code can be built. Complexity/Correctness In a large body of code, there can be a large number of dependencies between the various objects. The makefiles or other build descriptions for these objects can become very complex and difficult to understand or maintain. The dependencies can change as the system evolves. This can cause a given set of makefiles to become slightly incorrect over time, leading to race conditions and mysterious rare build failures. Dependency Cycles It might be desirable to organize code as cooperating shared objects, each of which draw on the resources provided by the other. Such cycles cannot be supported in an environment where objects must be built before the objects that use them, even though the runtime linker is fully capable of loading and using such objects if they could be built. Stub shared objects offer an alternative method for building code that sidesteps the above issues. Stub objects can be quickly built for all the shared objects produced by the build. Then, all the real shared objects and executables can be built in parallel, in any order, using the stub objects to stand in for the real objects at link-time. Afterwards, the executables and real shared objects are kept, and the stub shared objects are discarded. Stub objects are built from a mapfile, which must satisfy the following requirements. The mapfile must specify the STUB_OBJECT directive. This directive informs the link-editor that the object can be built as a stub object, and as such causes the link-editor to perform validation and sanity checking intended to guarantee that an object and its stub will always provide identical linking interfaces. All function and data symbols that make up the external interface to the object must be explicitly listed in the mapfile. The mapfile must use symbol scope reduction ('*'), to remove any symbols not explicitly listed from the external interface. All global data exported from the object must have an ASSERT symbol attribute in the mapfile to specify the symbol type, size, and bss attributes. In the case where there are multiple symbols that reference the same data, the ASSERT for one of these symbols must specify the TYPE and SIZE attributes, while the others must use the ALIAS attribute to reference this primary symbol. Given such a mapfile, the stub and real versions of the shared object can be built using the same command line for each, adding the '-z stub' option to the link for the stub object, and omiting the option from the link for the real object. To demonstrate these ideas, the following code implements a shared object named idx5, which exports data from a 5 element array of integers, with each element initialized to contain its zero-based array index. This data is available as a global array, via an alternative alias data symbol with weak binding, and via a functional interface. % cat idx5.c int _idx5[5] = { 0, 1, 2, 3, 4 }; #pragma weak idx5 = _idx5 int idx5_func(int index) { if ((index 4)) return (-1); return (_idx5[index]); } A mapfile is required to describe the interface provided by this shared object. % cat mapfile $mapfile_version 2 STUB_OBJECT; SYMBOL_SCOPE { _idx5 { ASSERT { TYPE=data; SIZE=4[5] }; }; idx5 { ASSERT { BINDING=weak; ALIAS=_idx5 }; }; idx5_func; local: *; }; The following main program is used to print all the index values available from the idx5 shared object. % cat main.c #include <stdio.h> extern int _idx5[5], idx5[5], idx5_func(int); int main(int argc, char **argv) { int i; for (i = 0; i The following commands create a stub version of this shared object in a subdirectory named stublib. elfdump is used to verify that the resulting object is a stub. The command used to build the stub differs from that of the real object only in the addition of the -z stub option, and the use of a different output file name. This demonstrates the ease with which stub generation can be added to an existing makefile. % cc -Kpic -G -M mapfile -h libidx5.so.1 idx5.c -o stublib/libidx5.so.1 -zstub % ln -s libidx5.so.1 stublib/libidx5.so % elfdump -d stublib/libidx5.so | grep STUB [11] FLAGS_1 0x4000000 [ STUB ] The main program can now be built, using the stub object to stand in for the real shared object, and setting a runpath that will find the real object at runtime. However, as we have not yet built the real object, this program cannot yet be run. Attempts to cause the system to load the stub object are rejected, as the runtime linker knows that stub objects lack the actual code and data found in the real object, and cannot execute. % cc main.c -L stublib -R '$ORIGIN/lib' -lidx5 -lc % ./a.out ld.so.1: a.out: fatal: libidx5.so.1: open failed: No such file or directory Killed % LD_PRELOAD=stublib/libidx5.so.1 ./a.out ld.so.1: a.out: fatal: stublib/libidx5.so.1: stub shared object cannot be used at runtime Killed We build the real object using the same command as we used to build the stub, omitting the -z stub option, and writing the results to a different file. % cc -Kpic -G -M mapfile -h libidx5.so.1 idx5.c -o lib/libidx5.so.1 Once the real object has been built in the lib subdirectory, the program can be run. % ./a.out [0] 0 0 0 [1] 1 1 1 [2] 2 2 2 [3] 3 3 3 [4] 4 4 4 Mapfile Changes The version 2 mapfile syntax was extended in a number of places to accommodate stub objects. Conditional Input The version 2 mapfile syntax has the ability conditionalize mapfile input using the $if control directive. As you might imagine, these directives are used frequently with ASSERT directives for data, because a given data symbol will frequently have a different size in 32 or 64-bit code, or on differing hardware such as x86 versus sparc. The link-editor maintains an internal table of names that can be used in the logical expressions evaluated by $if and $elif. At startup, this table is initialized with items that describe the class of object (_ELF32 or _ELF64) and the type of the target machine (_sparc or _x86). We found that there were a small number of cases in the Solaris code base in which we needed to know what kind of object we were producing, so we added the following new predefined items in order to address that need: NameMeaning ...... _ET_DYNshared object _ET_EXECexecutable object _ET_RELrelocatable object ...... STUB_OBJECT Directive The new STUB_OBJECT directive informs the link-editor that the object described by the mapfile can be built as a stub object. STUB_OBJECT; A stub shared object is built entirely from the information in the mapfiles supplied on the command line. When the -z stub option is specified to build a stub object, the presence of the STUB_OBJECT directive in a mapfile is required, and the link-editor uses the information in symbol ASSERT attributes to create global symbols that match those of the real object. When the real object is built, the presence of STUB_OBJECT causes the link-editor to verify that the mapfiles accurately describe the real object interface, and that a stub object built from them will provide the same linking interface as the real object it represents. All function and data symbols that make up the external interface to the object must be explicitly listed in the mapfile. The mapfile must use symbol scope reduction ('*'), to remove any symbols not explicitly listed from the external interface. All global data in the object is required to have an ASSERT attribute that specifies the symbol type and size. If the ASSERT BIND attribute is not present, the link-editor provides a default assertion that the symbol must be GLOBAL. If the ASSERT SH_ATTR attribute is not present, or does not specify that the section is one of BITS or NOBITS, the link-editor provides a default assertion that the associated section is BITS. All data symbols that describe the same address and size are required to have ASSERT ALIAS attributes specified in the mapfile. If aliased symbols are discovered that do not have an ASSERT ALIAS specified, the link fails and no object is produced. These rules ensure that the mapfiles contain a description of the real shared object's linking interface that is sufficient to produce a stub object with a completely compatible linking interface. SYMBOL_SCOPE/SYMBOL_VERSION ASSERT Attribute The SYMBOL_SCOPE and SYMBOL_VERSION mapfile directives were extended with a symbol attribute named ASSERT. The syntax for the ASSERT attribute is as follows: ASSERT { ALIAS = symbol_name; BINDING = symbol_binding; TYPE = symbol_type; SH_ATTR = section_attributes; SIZE = size_value; SIZE = size_value[count]; }; The ASSERT attribute is used to specify the expected characteristics of the symbol. The link-editor compares the symbol characteristics that result from the link to those given by ASSERT attributes. If the real and asserted attributes do not agree, a fatal error is issued and the output object is not created. In normal use, the link editor evaluates the ASSERT attribute when present, but does not require them, or provide default values for them. The presence of the STUB_OBJECT directive in a mapfile alters the interpretation of ASSERT to require them under some circumstances, and to supply default assertions if explicit ones are not present. See the definition of the STUB_OBJECT Directive for the details. When the -z stub command line option is specified to build a stub object, the information provided by ASSERT attributes is used to define the attributes of the global symbols provided by the object. ASSERT accepts the following: ALIAS Name of a previously defined symbol that this symbol is an alias for. An alias symbol has the same type, value, and size as the main symbol. The ALIAS attribute is mutually exclusive to the TYPE, SIZE, and SH_ATTR attributes, and cannot be used with them. When ALIAS is specified, the type, size, and section attributes are obtained from the alias symbol. BIND Specifies an ELF symbol binding, which can be any of the STB_ constants defined in <sys/elf.h>, with the STB_ prefix removed (e.g. GLOBAL, WEAK). TYPE Specifies an ELF symbol type, which can be any of the STT_ constants defined in <sys/elf.h>, with the STT_ prefix removed (e.g. OBJECT, COMMON, FUNC). In addition, for compatibility with other mapfile usage, FUNCTION and DATA can be specified, for STT_FUNC and STT_OBJECT, respectively. TYPE is mutually exclusive to ALIAS, and cannot be used in conjunction with it. SH_ATTR Specifies attributes of the section associated with the symbol. The section_attributes that can be specified are given in the following table: Section AttributeMeaning BITSSection is not of type SHT_NOBITS NOBITSSection is of type SHT_NOBITS SH_ATTR is mutually exclusive to ALIAS, and cannot be used in conjunction with it. SIZE Specifies the expected symbol size. SIZE is mutually exclusive to ALIAS, and cannot be used in conjunction with it. The syntax for the size_value argument is as described in the discussion of the SIZE attribute below. SIZE The SIZE symbol attribute existed before support for stub objects was introduced. It is used to set the size attribute of a given symbol. This attribute results in the creation of a symbol definition. Prior to the introduction of the ASSERT SIZE attribute, the value of a SIZE attribute was always numeric. While attempting to apply ASSERT SIZE to the objects in the Solaris ON consolidation, I found that many data symbols have a size based on the natural machine wordsize for the class of object being produced. Variables declared as long, or as a pointer, will be 4 bytes in size in a 32-bit object, and 8 bytes in a 64-bit object. Initially, I employed the conditional $if directive to handle these cases as follows: $if _ELF32 foo { ASSERT { TYPE=data; SIZE=4 } }; bar { ASSERT { TYPE=data; SIZE=20 } }; $elif _ELF64 foo { ASSERT { TYPE=data; SIZE=8 } }; bar { ASSERT { TYPE=data; SIZE=40 } }; $else $error UNKNOWN ELFCLASS $endif I found that the situation occurs frequently enough that this is cumbersome. To simplify this case, I introduced the idea of the addrsize symbolic name, and of a repeat count, which together make it simple to specify machine word scalar or array symbols. Both the SIZE, and ASSERT SIZE attributes support this syntax: The size_value argument can be a numeric value, or it can be the symbolic name addrsize. addrsize represents the size of a machine word capable of holding a memory address. The link-editor substitutes the value 4 for addrsize when building 32-bit objects, and the value 8 when building 64-bit objects. addrsize is useful for representing the size of pointer variables and C variables of type long, as it automatically adjusts for 32 and 64-bit objects without requiring the use of conditional input. The size_value argument can be optionally suffixed with a count value, enclosed in square brackets. If count is present, size_value and count are multiplied together to obtain the final size value. Using this feature, the example above can be written more naturally as: foo { ASSERT { TYPE=data; SIZE=addrsize } }; bar { ASSERT { TYPE=data; SIZE=addrsize[5] } }; Exported Global Data Is Still A Bad Idea As you can see, the additional plumbing added to the Solaris link-editor to support stub objects is minimal. Furthermore, about 90% of that plumbing is dedicated to handling global data. We have long advised against global data exported from shared objects. There are many ways in which global data does not fit well with dynamic linking. Stub objects simply provide one more reason to avoid this practice. It is always better to export all data via a functional interface. You should always hide your data, and make it available to your users via a function that they can call to acquire the address of the data item. However, If you do have to support global data for a stub, perhaps because you are working with an already existing object, it is still easilily done, as shown above. Oracle does not like us to discuss hypothetical new features that don't exist in shipping product, so I'll end this section with a speculation. It might be possible to do more in this area to ease the difficulty of dealing with objects that have global data that the users of the library don't need. Perhaps someday... Conclusions It is easy to create stub objects for most objects. If your library only exports function symbols, all you have to do to build a faithful stub object is to add STUB_OBJECT; and then to use the same link command you're currently using, with the addition of the -z stub option. Happy Stubbing!

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• Dynamically loading Assemblies to reduce Runtime Depencies

  - by Rick Strahl

  I've been working on a request to the West Wind Application Configuration library to add JSON support. The config library is a very easy to use code-first approach to configuration: You create a class that holds the configuration data that inherits from a base configuration class, and then assign a persistence provider at runtime that determines where and how the configuration data is store. Currently the library supports .NET Configuration stores (web.config/app.config), XML files, SQL records and string storage.About once a week somebody asks me about JSON support and I've deflected this question for the longest time because frankly I think that JSON as a configuration store doesn't really buy a heck of a lot over XML. Both formats require the user to perform some fixup of the plain configuration data - in XML into XML tags, with JSON using JSON delimiters for properties and property formatting rules. Sure JSON is a little less verbose and maybe a little easier to read if you have hierarchical data, but overall the differences are pretty minor in my opinion. And yet - the requests keep rolling in.Hard Link Issues in a Component LibraryAnother reason I've been hesitant is that I really didn't want to pull in a dependency on an external JSON library - in this case JSON.NET - into the core library. If you're not using JSON.NET elsewhere I don't want a user to have to require a hard dependency on JSON.NET unless they want to use the JSON feature. JSON.NET is also sensitive to versions and doesn't play nice with multiple versions when hard linked. For example, when you have a reference to V4.4 in your project but the host application has a reference to version 4.5 you can run into assembly load problems. NuGet's Update-Package can solve some of this *if* you can recompile, but that's not ideal for a component that's supposed to be just plug and play. This is no criticism of JSON.NET - this really applies to any dependency that might change.  So hard linking the DLL can be problematic for a number reasons, but the primary reason is to not force loading of JSON.NET unless you actually need it when you use the JSON configuration features of the library.Enter Dynamic LoadingSo rather than adding an assembly reference to the project, I decided that it would be better to dynamically load the DLL at runtime and then use dynamic typing to access various classes. This allows me to run without a hard assembly reference and allows more flexibility with version number differences now and in the future.But there are also a couple of downsides:No assembly reference means only dynamic access - no compiler type checking or IntellisenseRequirement for the host application to have reference to JSON.NET or else get runtime errorsThe former is minor, but the latter can be problematic. Runtime errors are always painful, but in this case I'm willing to live with this. If you want to use JSON configuration settings JSON.NET needs to be loaded in the project. If this is a Web project, it'll likely be there already.So there are a few things that are needed to make this work:Dynamically create an instance and optionally attempt to load an Assembly (if not loaded)Load types into dynamic variablesUse Reflection for a few tasks like statics/enumsThe dynamic keyword in C# makes the formerly most difficult Reflection part - method calls and property assignments - fairly painless. But as cool as dynamic is it doesn't handle all aspects of Reflection. Specifically it doesn't deal with object activation, truly dynamic (string based) member activation or accessing of non instance members, so there's still a little bit of work left to do with Reflection.Dynamic Object InstantiationThe first step in getting the process rolling is to instantiate the type you need to work with. This might be a two step process - loading the instance from a string value, since we don't have a hard type reference and potentially having to load the assembly. Although the host project might have a reference to JSON.NET, that instance might have not been loaded yet since it hasn't been accessed yet. In ASP.NET this won't be a problem, since ASP.NET preloads all referenced assemblies on AppDomain startup, but in other executable project, assemblies are just in time loaded only when they are accessed.Instantiating a type is a two step process: Finding the type reference and then activating it. Here's the generic code out of my ReflectionUtils library I use for this:/// <summary> /// Creates an instance of a type based on a string. Assumes that the type's /// </summary> /// <param name="typeName">Common name of the type</param> /// <param name="args">Any constructor parameters</param> /// <returns></returns> public static object CreateInstanceFromString(string typeName, params object[] args) { object instance = null; Type type = null; try { type = GetTypeFromName(typeName); if (type == null) return null; instance = Activator.CreateInstance(type, args); } catch { return null; } return instance; } /// <summary> /// Helper routine that looks up a type name and tries to retrieve the /// full type reference in the actively executing assemblies. /// </summary> /// <param name="typeName"></param> /// <returns></returns> public static Type GetTypeFromName(string typeName) { Type type = null; // Let default name binding find it type = Type.GetType(typeName, false); if (type != null) return type; // look through assembly list var assemblies = AppDomain.CurrentDomain.GetAssemblies(); // try to find manually foreach (Assembly asm in assemblies) { type = asm.GetType(typeName, false); if (type != null) break; } return type; } To use this for loading JSON.NET I have a small factory function that instantiates JSON.NET and sets a bunch of configuration settings on the generated object. The startup code also looks for failure and tries loading up the assembly when it fails since that's the main reason the load would fail. Finally it also caches the loaded instance for reuse (according to James the JSON.NET instance is thread safe and quite a bit faster when cached). Here's what the factory function looks like in JsonSerializationUtils:/// <summary> /// Dynamically creates an instance of JSON.NET /// </summary> /// <param name="throwExceptions">If true throws exceptions otherwise returns null</param> /// <returns>Dynamic JsonSerializer instance</returns> public static dynamic CreateJsonNet(bool throwExceptions = true) { if (JsonNet != null) return JsonNet; lock (SyncLock) { if (JsonNet != null) return JsonNet; // Try to create instance dynamic json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); if (json == null) { try { var ass = AppDomain.CurrentDomain.Load("Newtonsoft.Json"); json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); } catch (Exception ex) { if (throwExceptions) throw; return null; } } if (json == null) return null; json.ReferenceLoopHandling = (dynamic) ReflectionUtils.GetStaticProperty("Newtonsoft.Json.ReferenceLoopHandling", "Ignore"); // Enums as strings in JSON dynamic enumConverter = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.Converters.StringEnumConverter"); json.Converters.Add(enumConverter); JsonNet = json; } return JsonNet; }This code's purpose is to return a fully configured JsonSerializer instance. As you can see the code tries to create an instance and when it fails tries to load the assembly, and then re-tries loading.Once the instance is loaded some configuration occurs on it. Specifically I set the ReferenceLoopHandling option to not blow up immediately when circular references are encountered. There are a host of other small config setting that might be useful to set, but the default seem to be good enough in recent versions. Note that I'm setting ReferenceLoopHandling which requires an Enum value to be set. There's no real easy way (short of using the cardinal numeric value) to set a property or pass parameters from static values or enums. This means I still need to use Reflection to make this work. I'm using the same ReflectionUtils class I previously used to handle this for me. The function looks up the type and then uses Type.InvokeMember() to read the static property.Another feature I need is have Enum values serialized as strings rather than numeric values which is the default. To do this I can use the StringEnumConverter to convert enums to strings by adding it to the Converters collection.As you can see there's still a bit of Reflection to be done even in C# 4+ with dynamic, but with a few helpers this process is relatively painless.Doing the actual JSON ConversionFinally I need to actually do my JSON conversions. For the Utility class I need serialization that works for both strings and files so I created four methods that handle these tasks two each for serialization and deserialization for string and file.Here's what the File Serialization looks like:/// <summary> /// Serializes an object instance to a JSON file. /// </summary> /// <param name="value">the value to serialize</param> /// <param name="fileName">Full path to the file to write out with JSON.</param> /// <param name="throwExceptions">Determines whether exceptions are thrown or false is returned</param> /// <param name="formatJsonOutput">if true pretty-formats the JSON with line breaks</param> /// <returns>true or false</returns> public static bool SerializeToFile(object value, string fileName, bool throwExceptions = false, bool formatJsonOutput = false) { dynamic writer = null; FileStream fs = null; try { Type type = value.GetType(); var json = CreateJsonNet(throwExceptions); if (json == null) return false; fs = new FileStream(fileName, FileMode.Create); var sw = new StreamWriter(fs, Encoding.UTF8); writer = Activator.CreateInstance(JsonTextWriterType, sw); if (formatJsonOutput) writer.Formatting = (dynamic)Enum.Parse(FormattingType, "Indented"); writer.QuoteChar = '"'; json.Serialize(writer, value); } catch (Exception ex) { Debug.WriteLine("JsonSerializer Serialize error: " + ex.Message); if (throwExceptions) throw; return false; } finally { if (writer != null) writer.Close(); if (fs != null) fs.Close(); } return true; }You can see more of the dynamic invocation in this code. First I grab the dynamic JsonSerializer instance using the CreateJsonNet() method shown earlier which returns a dynamic. I then create a JsonTextWriter and configure a couple of enum settings on it, and then call Serialize() on the serializer instance with the JsonTextWriter that writes the output to disk. Although this code is dynamic it's still fairly short and readable.For full circle operation here's the DeserializeFromFile() version:/// <summary> /// Deserializes an object from file and returns a reference. /// </summary> /// <param name="fileName">name of the file to serialize to</param> /// <param name="objectType">The Type of the object. Use typeof(yourobject class)</param> /// <param name="binarySerialization">determines whether we use Xml or Binary serialization</param> /// <param name="throwExceptions">determines whether failure will throw rather than return null on failure</param> /// <returns>Instance of the deserialized object or null. Must be cast to your object type</returns> public static object DeserializeFromFile(string fileName, Type objectType, bool throwExceptions = false) { dynamic json = CreateJsonNet(throwExceptions); if (json == null) return null; object result = null; dynamic reader = null; FileStream fs = null; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); var sr = new StreamReader(fs, Encoding.UTF8); reader = Activator.CreateInstance(JsonTextReaderType, sr); result = json.Deserialize(reader, objectType); reader.Close(); } catch (Exception ex) { Debug.WriteLine("JsonNetSerialization Deserialization Error: " + ex.Message); if (throwExceptions) throw; return null; } finally { if (reader != null) reader.Close(); if (fs != null) fs.Close(); } return result; }This code is a little more compact since there are no prettifying options to set. Here JsonTextReader is created dynamically and it receives the output from the Deserialize() operation on the serializer.You can take a look at the full JsonSerializationUtils.cs file on GitHub to see the rest of the operations, but the string operations are very similar - the code is fairly repetitive.These generic serialization utilities isolate the dynamic serialization logic that has to deal with the dynamic nature of JSON.NET, and any code that uses these functions is none the wiser that JSON.NET is dynamically loaded.Using the JsonSerializationUtils WrapperThe final consumer of the SerializationUtils wrapper is an actual ConfigurationProvider, that is responsible for handling reading and writing JSON values to and from files. The provider is simple a small wrapper around the SerializationUtils component and there's very little code to make this work now:The whole provider looks like this:/// <summary> /// Reads and Writes configuration settings in .NET config files and /// sections. Allows reading and writing to default or external files /// and specification of the configuration section that settings are /// applied to. /// </summary> public class JsonFileConfigurationProvider<TAppConfiguration> : ConfigurationProviderBase<TAppConfiguration> where TAppConfiguration: AppConfiguration, new() { /// <summary> /// Optional - the Configuration file where configuration settings are /// stored in. If not specified uses the default Configuration Manager /// and its default store. /// </summary> public string JsonConfigurationFile { get { return _JsonConfigurationFile; } set { _JsonConfigurationFile = value; } } private string _JsonConfigurationFile = string.Empty; public override bool Read(AppConfiguration config) { var newConfig = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfiguration)) as TAppConfiguration; if (newConfig == null) { if(Write(config)) return true; return false; } DecryptFields(newConfig); DataUtils.CopyObjectData(newConfig, config, "Provider,ErrorMessage"); return true; } /// <summary> /// Return /// </summary> /// <typeparam name="TAppConfig"></typeparam> /// <returns></returns> public override TAppConfig Read<TAppConfig>() { var result = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfig)) as TAppConfig; if (result != null) DecryptFields(result); return result; } /// <summary> /// Write configuration to XmlConfigurationFile location /// </summary> /// <param name="config"></param> /// <returns></returns> public override bool Write(AppConfiguration config) { EncryptFields(config); bool result = JsonSerializationUtils.SerializeToFile(config, JsonConfigurationFile,false,true); // Have to decrypt again to make sure the properties are readable afterwards DecryptFields(config); return result; } }This incidentally demonstrates how easy it is to create a new provider for the West Wind Application Configuration component. Simply implementing 3 methods will do in most cases.Note this code doesn't have any dynamic dependencies - all that's abstracted away in the JsonSerializationUtils(). From here on, serializing JSON is just a matter of calling the static methods on the SerializationUtils class.Already, there are several other places in some other tools where I use JSON serialization this is coming in very handy. With a couple of lines of code I was able to add JSON.NET support to an older AJAX library that I use replacing quite a bit of code that was previously in use. And for any other manual JSON operations (in a couple of apps I use JSON Serialization for 'blob' like document storage) this is also going to be handy.Performance?Some of you might be thinking that using dynamic and Reflection can't be good for performance. And you'd be right… In performing some informal testing it looks like the performance of the native code is nearly twice as fast as the dynamic code. Most of the slowness is attributable to type lookups. To test I created a native class that uses an actual reference to JSON.NET and performance was consistently around 85-90% faster with the referenced code. That being said though - I serialized 10,000 objects in 80ms vs. 45ms so this isn't hardly slouchy. For the configuration component speed is not that important because both read and write operations typically happen once on first access and then every once in a while. But for other operations - say a serializer trying to handle AJAX requests on a Web Server one would be well served to create a hard dependency.Dynamic Loading - Worth it?On occasion dynamic loading makes sense. But there's a price to be paid in added code complexity and a performance hit. But for some operations that are not pivotal to a component or application and only used under certain circumstances dynamic loading can be beneficial to avoid having to ship extra files and loading down distributions. These days when you create new projects in Visual Studio with 30 assemblies before you even add your own code, trying to keep file counts under control seems a good idea. It's not the kind of thing you do on a regular basis, but when needed it can be a useful tool. Hopefully some of you find this information useful…© Rick Strahl, West Wind Technologies, 2005-2013Posted in .NET  C#   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Error compiling GLib in Ubuntu 14.04 (trying to install GimpShop)

  - by Nicolás Salvarrey

  I'm kinda new in Linux, so please take it easy on the most complicated stuff. I'm trying to install GimpShop. Installation guide asks me to install GLib first, and when I try to compile it using the make command I get errors. When I run the ./configure --prefix=/usr command, I get this: checking for a BSD-compatible install... /usr/bin/install -c checking whether build environment is sane... yes checking for gawk... no checking for mawk... mawk checking whether make sets $(MAKE)... yes checking whether to enable maintainer-specific portions of Makefiles... no checking build system type... x86_64-unknown-linux-gnu checking host system type... x86_64-unknown-linux-gnu checking for the BeOS... no checking for Win32... no checking whether to enable garbage collector friendliness... no checking whether to disable memory pools... no checking for gcc... gcc checking for C compiler default output file name... a.out checking whether the C compiler works... yes checking whether we are cross compiling... no checking for suffix of executables... checking for suffix of object files... o checking whether we are using the GNU C compiler... yes checking whether gcc accepts -g... yes checking for gcc option to accept ANSI C... none needed checking for style of include used by make... GNU checking dependency style of gcc... gcc3 checking for c++... no checking for g++... no checking for gcc... gcc checking whether we are using the GNU C++ compiler... no checking whether gcc accepts -g... no checking dependency style of gcc... gcc3 checking for gcc option to accept ANSI C... none needed checking for a BSD-compatible install... /usr/bin/install -c checking for special C compiler options needed for large files... no checking for _FILE_OFFSET_BITS value needed for large files... no checking for _LARGE_FILES value needed for large files... no checking for pkg-config... /usr/bin/pkg-config checking for gawk... (cached) mawk checking for perl5... no checking for perl... perl checking for indent... no checking for perl... /usr/bin/perl checking for iconv_open... yes checking how to run the C preprocessor... gcc -E checking for egrep... grep -E checking for ANSI C header files... yes checking for sys/types.h... yes checking for sys/stat.h... yes checking for stdlib.h... yes checking for string.h... yes checking for memory.h... yes checking for strings.h... yes checking for inttypes.h... yes checking for stdint.h... yes checking for unistd.h... yes checking locale.h usability... yes checking locale.h presence... yes checking for locale.h... yes checking for LC_MESSAGES... yes checking libintl.h usability... yes checking libintl.h presence... yes checking for libintl.h... yes checking for ngettext in libc... yes checking for dgettext in libc... yes checking for bind_textdomain_codeset... yes checking for msgfmt... /usr/bin/msgfmt checking for dcgettext... yes checking for gmsgfmt... /usr/bin/msgfmt checking for xgettext... /usr/bin/xgettext checking for catalogs to be installed... am ar az be bg bn bs ca cs cy da de el en_CA en_GB eo es et eu fa fi fr ga gl gu he hi hr id is it ja ko lt lv mk mn ms nb ne nl nn no or pa pl pt pt_BR ro ru sk sl sq sr sr@ije sr@Latn sv ta tl tr uk vi wa xh yi zh_CN zh_TW checking for a sed that does not truncate output... /bin/sed checking for ld used by gcc... /usr/bin/ld checking if the linker (/usr/bin/ld) is GNU ld... yes checking for /usr/bin/ld option to reload object files... -r checking for BSD-compatible nm... /usr/bin/nm -B checking whether ln -s works... yes checking how to recognise dependent libraries... pass_all checking dlfcn.h usability... yes checking dlfcn.h presence... yes checking for dlfcn.h... yes checking for g77... no checking for f77... no checking for xlf... no checking for frt... no checking for pgf77... no checking for fort77... no checking for fl32... no checking for af77... no checking for f90... no checking for xlf90... no checking for pgf90... no checking for epcf90... no checking for f95... no checking for fort... no checking for xlf95... no checking for ifc... no checking for efc... no checking for pgf95... no checking for lf95... no checking for gfortran... no checking whether we are using the GNU Fortran 77 compiler... no checking whether accepts -g... no checking the maximum length of command line arguments... 32768 checking command to parse /usr/bin/nm -B output from gcc object... ok checking for objdir... .libs checking for ar... ar checking for ranlib... ranlib checking for strip... strip checking if gcc static flag works... yes checking if gcc supports -fno-rtti -fno-exceptions... no checking for gcc option to produce PIC... -fPIC checking if gcc PIC flag -fPIC works... yes checking if gcc supports -c -o file.o... yes checking whether the gcc linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes checking whether -lc should be explicitly linked in... no checking dynamic linker characteristics... GNU/Linux ld.so checking how to hardcode library paths into programs... immediate checking whether stripping libraries is possible... yes checking if libtool supports shared libraries... yes checking whether to build shared libraries... yes checking whether to build static libraries... no configure: creating libtool appending configuration tag "CXX" to libtool appending configuration tag "F77" to libtool checking for extra flags to get ANSI library prototypes... none needed checking for extra flags for POSIX compliance... none needed checking for ANSI C header files... (cached) yes checking for vprintf... yes checking for _doprnt... no checking for working alloca.h... yes checking for alloca... yes checking for atexit... yes checking for on_exit... yes checking for char... yes checking size of char... 1 checking for short... yes checking size of short... 2 checking for long... yes checking size of long... 8 checking for int... yes checking size of int... 4 checking for void *... yes checking size of void *... 8 checking for long long... yes checking size of long long... 8 checking for __int64... no checking size of __int64... 0 checking for format to printf and scanf a guint64... %llu checking for an ANSI C-conforming const... yes checking if malloc() and friends prototypes are gmem.h compatible... no checking for growing stack pointer... yes checking for __inline... yes checking for __inline__... yes checking for inline... yes checking if inline functions in headers work... yes checking for ISO C99 varargs macros in C... yes checking for ISO C99 varargs macros in C++... no checking for GNUC varargs macros... yes checking for GNUC visibility attribute... yes checking whether byte ordering is bigendian... no checking dirent.h usability... yes checking dirent.h presence... yes checking for dirent.h... yes checking float.h usability... yes checking float.h presence... yes checking for float.h... yes checking limits.h usability... yes checking limits.h presence... yes checking for limits.h... yes checking pwd.h usability... yes checking pwd.h presence... yes checking for pwd.h... yes checking sys/param.h usability... yes checking sys/param.h presence... yes checking for sys/param.h... yes checking sys/poll.h usability... yes checking sys/poll.h presence... yes checking for sys/poll.h... yes checking sys/select.h usability... yes checking sys/select.h presence... yes checking for sys/select.h... yes checking for sys/types.h... (cached) yes checking sys/time.h usability... yes checking sys/time.h presence... yes checking for sys/time.h... yes checking sys/times.h usability... yes checking sys/times.h presence... yes checking for sys/times.h... yes checking for unistd.h... (cached) yes checking values.h usability... yes checking values.h presence... yes checking for values.h... yes checking for stdint.h... (cached) yes checking sched.h usability... yes checking sched.h presence... yes checking for sched.h... yes checking langinfo.h usability... yes checking langinfo.h presence... yes checking for langinfo.h... yes checking for nl_langinfo... yes checking for nl_langinfo and CODESET... yes checking whether we are using the GNU C Library 2.1 or newer... yes checking stddef.h usability... yes checking stddef.h presence... yes checking for stddef.h... yes checking for stdlib.h... (cached) yes checking for string.h... (cached) yes checking for setlocale... yes checking for size_t... yes checking size of size_t... 8 checking for the appropriate definition for size_t... unsigned long checking for lstat... yes checking for strerror... yes checking for strsignal... yes checking for memmove... yes checking for mkstemp... yes checking for vsnprintf... yes checking for stpcpy... yes checking for strcasecmp... yes checking for strncasecmp... yes checking for poll... yes checking for getcwd... yes checking for nanosleep... yes checking for vasprintf... yes checking for setenv... yes checking for unsetenv... yes checking for getc_unlocked... yes checking for readlink... yes checking for symlink... yes checking for C99 vsnprintf... yes checking whether printf supports positional parameters... yes checking for signed... yes checking for long long... (cached) yes checking for long double... yes checking for wchar_t... yes checking for wint_t... yes checking for size_t... (cached) yes checking for ptrdiff_t... yes checking for inttypes.h... yes checking for stdint.h... yes checking for snprintf... yes checking for C99 snprintf... yes checking for sys_errlist... yes checking for sys_siglist... yes checking for sys_siglist declaration... yes checking for fd_set... yes, found in sys/types.h checking whether realloc (NULL,) will work... yes checking for nl_langinfo (CODESET)... yes checking for OpenBSD strlcpy/strlcat... no checking for an implementation of va_copy()... yes checking for an implementation of __va_copy()... yes checking whether va_lists can be copied by value... no checking for dlopen... no checking for NSLinkModule... no checking for dlopen in -ldl... yes checking for dlsym in -ldl... yes checking for RTLD_GLOBAL brokenness... no checking for preceeding underscore in symbols... no checking for dlerror... yes checking for the suffix of shared libraries... .so checking for gspawn implementation... gspawn.lo checking for GIOChannel implementation... giounix.lo checking for platform-dependent source... checking whether to compile timeloop... yes checking if building for some Win32 platform... no checking for thread implementation... posix checking thread related cflags... -pthread checking for sched_get_priority_min... yes checking thread related libraries... -pthread checking for localtime_r... yes checking for posix getpwuid_r... yes checking size of pthread_t... 8 checking for pthread_attr_setstacksize... yes checking for minimal/maximal thread priority... sched_get_priority_min(SCHED_OTHER)/sched_get_priority_max(SCHED_OTHER) checking for pthread_setschedparam... yes checking for posix yield function... sched_yield checking size of pthread_mutex_t... 40 checking byte contents of PTHREAD_MUTEX_INITIALIZER... 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 checking whether to use assembler code for atomic operations... x86_64 checking value of POLLIN... 1 checking value of POLLOUT... 4 checking value of POLLPRI... 2 checking value of POLLERR... 8 checking value of POLLHUP... 16 checking value of POLLNVAL... 32 checking for EILSEQ... yes configure: creating ./config.status config.status: creating glib-2.0.pc config.status: creating glib-2.0-uninstalled.pc config.status: creating gmodule-2.0.pc config.status: creating gmodule-no-export-2.0.pc config.status: creating gmodule-2.0-uninstalled.pc config.status: creating gthread-2.0.pc config.status: creating gthread-2.0-uninstalled.pc config.status: creating gobject-2.0.pc config.status: creating gobject-2.0-uninstalled.pc config.status: creating glib-zip config.status: creating glib-gettextize config.status: creating Makefile config.status: creating build/Makefile config.status: creating build/win32/Makefile config.status: creating build/win32/dirent/Makefile config.status: creating glib/Makefile config.status: creating glib/libcharset/Makefile config.status: creating glib/gnulib/Makefile config.status: creating gmodule/Makefile config.status: creating gmodule/gmoduleconf.h config.status: creating gobject/Makefile config.status: creating gobject/glib-mkenums config.status: creating gthread/Makefile config.status: creating po/Makefile.in config.status: creating docs/Makefile config.status: creating docs/reference/Makefile config.status: creating docs/reference/glib/Makefile config.status: creating docs/reference/glib/version.xml config.status: creating docs/reference/gobject/Makefile config.status: creating docs/reference/gobject/version.xml config.status: creating tests/Makefile config.status: creating tests/gobject/Makefile config.status: creating m4macros/Makefile config.status: creating config.h config.status: config.h is unchanged config.status: executing depfiles commands config.status: executing default-1 commands config.status: executing glibconfig.h commands config.status: glibconfig.h is unchanged config.status: executing chmod-scripts commands nsalvarrey@Delleuze:~/glib-2.6.3$ ^C nsalvarrey@Delleuze:~/glib-2.6.3$ And then, with the make command, I get this: galias.h:83:39: error: 'g_ascii_digit_value' aliased to undefined symbol 'IA__g_ascii_digit_value' extern __typeof (g_ascii_digit_value) g_ascii_digit_value __attribute((alias("IA__g_ascii_digit_value"), visibility("default"))); ^ In file included from garray.c:35:0: galias.h:31:35: error: 'g_allocator_new' aliased to undefined symbol 'IA__g_allocator_new' extern __typeof (g_allocator_new) g_allocator_new __attribute((alias("IA__g_allocator_new"), visibility("default"))); ^ make[4]: *** [garray.lo] Error 1 make[4]: se sale del directorio «/home/nsalvarrey/glib-2.6.3/glib» make[3]: *** [all-recursive] Error 1 make[3]: se sale del directorio «/home/nsalvarrey/glib-2.6.3/glib» make[2]: *** [all] Error 2 make[2]: se sale del directorio «/home/nsalvarrey/glib-2.6.3/glib» make[1]: *** [all-recursive] Error 1 make[1]: se sale del directorio «/home/nsalvarrey/glib-2.6.3» make: *** [all] Error 2 nsalvarrey@Delleuze:~/glib-2.6.3$ (it's actually a lot longer) Can somebody help me?

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• Dynamically loading Assemblies to reduce Runtime Dependencies

  - by Rick Strahl

  I've been working on a request to the West Wind Application Configuration library to add JSON support. The config library is a very easy to use code-first approach to configuration: You create a class that holds the configuration data that inherits from a base configuration class, and then assign a persistence provider at runtime that determines where and how the configuration data is store. Currently the library supports .NET Configuration stores (web.config/app.config), XML files, SQL records and string storage.About once a week somebody asks me about JSON support and I've deflected this question for the longest time because frankly I think that JSON as a configuration store doesn't really buy a heck of a lot over XML. Both formats require the user to perform some fixup of the plain configuration data - in XML into XML tags, with JSON using JSON delimiters for properties and property formatting rules. Sure JSON is a little less verbose and maybe a little easier to read if you have hierarchical data, but overall the differences are pretty minor in my opinion. And yet - the requests keep rolling in.Hard Link Issues in a Component LibraryAnother reason I've been hesitant is that I really didn't want to pull in a dependency on an external JSON library - in this case JSON.NET - into the core library. If you're not using JSON.NET elsewhere I don't want a user to have to require a hard dependency on JSON.NET unless they want to use the JSON feature. JSON.NET is also sensitive to versions and doesn't play nice with multiple versions when hard linked. For example, when you have a reference to V4.4 in your project but the host application has a reference to version 4.5 you can run into assembly load problems. NuGet's Update-Package can solve some of this *if* you can recompile, but that's not ideal for a component that's supposed to be just plug and play. This is no criticism of JSON.NET - this really applies to any dependency that might change.  So hard linking the DLL can be problematic for a number reasons, but the primary reason is to not force loading of JSON.NET unless you actually need it when you use the JSON configuration features of the library.Enter Dynamic LoadingSo rather than adding an assembly reference to the project, I decided that it would be better to dynamically load the DLL at runtime and then use dynamic typing to access various classes. This allows me to run without a hard assembly reference and allows more flexibility with version number differences now and in the future.But there are also a couple of downsides:No assembly reference means only dynamic access - no compiler type checking or IntellisenseRequirement for the host application to have reference to JSON.NET or else get runtime errorsThe former is minor, but the latter can be problematic. Runtime errors are always painful, but in this case I'm willing to live with this. If you want to use JSON configuration settings JSON.NET needs to be loaded in the project. If this is a Web project, it'll likely be there already.So there are a few things that are needed to make this work:Dynamically create an instance and optionally attempt to load an Assembly (if not loaded)Load types into dynamic variablesUse Reflection for a few tasks like statics/enumsThe dynamic keyword in C# makes the formerly most difficult Reflection part - method calls and property assignments - fairly painless. But as cool as dynamic is it doesn't handle all aspects of Reflection. Specifically it doesn't deal with object activation, truly dynamic (string based) member activation or accessing of non instance members, so there's still a little bit of work left to do with Reflection.Dynamic Object InstantiationThe first step in getting the process rolling is to instantiate the type you need to work with. This might be a two step process - loading the instance from a string value, since we don't have a hard type reference and potentially having to load the assembly. Although the host project might have a reference to JSON.NET, that instance might have not been loaded yet since it hasn't been accessed yet. In ASP.NET this won't be a problem, since ASP.NET preloads all referenced assemblies on AppDomain startup, but in other executable project, assemblies are just in time loaded only when they are accessed.Instantiating a type is a two step process: Finding the type reference and then activating it. Here's the generic code out of my ReflectionUtils library I use for this:/// <summary> /// Creates an instance of a type based on a string. Assumes that the type's /// </summary> /// <param name="typeName">Common name of the type</param> /// <param name="args">Any constructor parameters</param> /// <returns></returns> public static object CreateInstanceFromString(string typeName, params object[] args) { object instance = null; Type type = null; try { type = GetTypeFromName(typeName); if (type == null) return null; instance = Activator.CreateInstance(type, args); } catch { return null; } return instance; } /// <summary> /// Helper routine that looks up a type name and tries to retrieve the /// full type reference in the actively executing assemblies. /// </summary> /// <param name="typeName"></param> /// <returns></returns> public static Type GetTypeFromName(string typeName) { Type type = null; // Let default name binding find it type = Type.GetType(typeName, false); if (type != null) return type; // look through assembly list var assemblies = AppDomain.CurrentDomain.GetAssemblies(); // try to find manually foreach (Assembly asm in assemblies) { type = asm.GetType(typeName, false); if (type != null) break; } return type; } To use this for loading JSON.NET I have a small factory function that instantiates JSON.NET and sets a bunch of configuration settings on the generated object. The startup code also looks for failure and tries loading up the assembly when it fails since that's the main reason the load would fail. Finally it also caches the loaded instance for reuse (according to James the JSON.NET instance is thread safe and quite a bit faster when cached). Here's what the factory function looks like in JsonSerializationUtils:/// <summary> /// Dynamically creates an instance of JSON.NET /// </summary> /// <param name="throwExceptions">If true throws exceptions otherwise returns null</param> /// <returns>Dynamic JsonSerializer instance</returns> public static dynamic CreateJsonNet(bool throwExceptions = true) { if (JsonNet != null) return JsonNet; lock (SyncLock) { if (JsonNet != null) return JsonNet; // Try to create instance dynamic json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); if (json == null) { try { var ass = AppDomain.CurrentDomain.Load("Newtonsoft.Json"); json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); } catch (Exception ex) { if (throwExceptions) throw; return null; } } if (json == null) return null; json.ReferenceLoopHandling = (dynamic) ReflectionUtils.GetStaticProperty("Newtonsoft.Json.ReferenceLoopHandling", "Ignore"); // Enums as strings in JSON dynamic enumConverter = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.Converters.StringEnumConverter"); json.Converters.Add(enumConverter); JsonNet = json; } return JsonNet; }This code's purpose is to return a fully configured JsonSerializer instance. As you can see the code tries to create an instance and when it fails tries to load the assembly, and then re-tries loading.Once the instance is loaded some configuration occurs on it. Specifically I set the ReferenceLoopHandling option to not blow up immediately when circular references are encountered. There are a host of other small config setting that might be useful to set, but the default seem to be good enough in recent versions. Note that I'm setting ReferenceLoopHandling which requires an Enum value to be set. There's no real easy way (short of using the cardinal numeric value) to set a property or pass parameters from static values or enums. This means I still need to use Reflection to make this work. I'm using the same ReflectionUtils class I previously used to handle this for me. The function looks up the type and then uses Type.InvokeMember() to read the static property.Another feature I need is have Enum values serialized as strings rather than numeric values which is the default. To do this I can use the StringEnumConverter to convert enums to strings by adding it to the Converters collection.As you can see there's still a bit of Reflection to be done even in C# 4+ with dynamic, but with a few helpers this process is relatively painless.Doing the actual JSON ConversionFinally I need to actually do my JSON conversions. For the Utility class I need serialization that works for both strings and files so I created four methods that handle these tasks two each for serialization and deserialization for string and file.Here's what the File Serialization looks like:/// <summary> /// Serializes an object instance to a JSON file. /// </summary> /// <param name="value">the value to serialize</param> /// <param name="fileName">Full path to the file to write out with JSON.</param> /// <param name="throwExceptions">Determines whether exceptions are thrown or false is returned</param> /// <param name="formatJsonOutput">if true pretty-formats the JSON with line breaks</param> /// <returns>true or false</returns> public static bool SerializeToFile(object value, string fileName, bool throwExceptions = false, bool formatJsonOutput = false) { dynamic writer = null; FileStream fs = null; try { Type type = value.GetType(); var json = CreateJsonNet(throwExceptions); if (json == null) return false; fs = new FileStream(fileName, FileMode.Create); var sw = new StreamWriter(fs, Encoding.UTF8); writer = Activator.CreateInstance(JsonTextWriterType, sw); if (formatJsonOutput) writer.Formatting = (dynamic)Enum.Parse(FormattingType, "Indented"); writer.QuoteChar = '"'; json.Serialize(writer, value); } catch (Exception ex) { Debug.WriteLine("JsonSerializer Serialize error: " + ex.Message); if (throwExceptions) throw; return false; } finally { if (writer != null) writer.Close(); if (fs != null) fs.Close(); } return true; }You can see more of the dynamic invocation in this code. First I grab the dynamic JsonSerializer instance using the CreateJsonNet() method shown earlier which returns a dynamic. I then create a JsonTextWriter and configure a couple of enum settings on it, and then call Serialize() on the serializer instance with the JsonTextWriter that writes the output to disk. Although this code is dynamic it's still fairly short and readable.For full circle operation here's the DeserializeFromFile() version:/// <summary> /// Deserializes an object from file and returns a reference. /// </summary> /// <param name="fileName">name of the file to serialize to</param> /// <param name="objectType">The Type of the object. Use typeof(yourobject class)</param> /// <param name="binarySerialization">determines whether we use Xml or Binary serialization</param> /// <param name="throwExceptions">determines whether failure will throw rather than return null on failure</param> /// <returns>Instance of the deserialized object or null. Must be cast to your object type</returns> public static object DeserializeFromFile(string fileName, Type objectType, bool throwExceptions = false) { dynamic json = CreateJsonNet(throwExceptions); if (json == null) return null; object result = null; dynamic reader = null; FileStream fs = null; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); var sr = new StreamReader(fs, Encoding.UTF8); reader = Activator.CreateInstance(JsonTextReaderType, sr); result = json.Deserialize(reader, objectType); reader.Close(); } catch (Exception ex) { Debug.WriteLine("JsonNetSerialization Deserialization Error: " + ex.Message); if (throwExceptions) throw; return null; } finally { if (reader != null) reader.Close(); if (fs != null) fs.Close(); } return result; }This code is a little more compact since there are no prettifying options to set. Here JsonTextReader is created dynamically and it receives the output from the Deserialize() operation on the serializer.You can take a look at the full JsonSerializationUtils.cs file on GitHub to see the rest of the operations, but the string operations are very similar - the code is fairly repetitive.These generic serialization utilities isolate the dynamic serialization logic that has to deal with the dynamic nature of JSON.NET, and any code that uses these functions is none the wiser that JSON.NET is dynamically loaded.Using the JsonSerializationUtils WrapperThe final consumer of the SerializationUtils wrapper is an actual ConfigurationProvider, that is responsible for handling reading and writing JSON values to and from files. The provider is simple a small wrapper around the SerializationUtils component and there's very little code to make this work now:The whole provider looks like this:/// <summary> /// Reads and Writes configuration settings in .NET config files and /// sections. Allows reading and writing to default or external files /// and specification of the configuration section that settings are /// applied to. /// </summary> public class JsonFileConfigurationProvider<TAppConfiguration> : ConfigurationProviderBase<TAppConfiguration> where TAppConfiguration: AppConfiguration, new() { /// <summary> /// Optional - the Configuration file where configuration settings are /// stored in. If not specified uses the default Configuration Manager /// and its default store. /// </summary> public string JsonConfigurationFile { get { return _JsonConfigurationFile; } set { _JsonConfigurationFile = value; } } private string _JsonConfigurationFile = string.Empty; public override bool Read(AppConfiguration config) { var newConfig = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfiguration)) as TAppConfiguration; if (newConfig == null) { if(Write(config)) return true; return false; } DecryptFields(newConfig); DataUtils.CopyObjectData(newConfig, config, "Provider,ErrorMessage"); return true; } /// <summary> /// Return /// </summary> /// <typeparam name="TAppConfig"></typeparam> /// <returns></returns> public override TAppConfig Read<TAppConfig>() { var result = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfig)) as TAppConfig; if (result != null) DecryptFields(result); return result; } /// <summary> /// Write configuration to XmlConfigurationFile location /// </summary> /// <param name="config"></param> /// <returns></returns> public override bool Write(AppConfiguration config) { EncryptFields(config); bool result = JsonSerializationUtils.SerializeToFile(config, JsonConfigurationFile,false,true); // Have to decrypt again to make sure the properties are readable afterwards DecryptFields(config); return result; } }This incidentally demonstrates how easy it is to create a new provider for the West Wind Application Configuration component. Simply implementing 3 methods will do in most cases.Note this code doesn't have any dynamic dependencies - all that's abstracted away in the JsonSerializationUtils(). From here on, serializing JSON is just a matter of calling the static methods on the SerializationUtils class.Already, there are several other places in some other tools where I use JSON serialization this is coming in very handy. With a couple of lines of code I was able to add JSON.NET support to an older AJAX library that I use replacing quite a bit of code that was previously in use. And for any other manual JSON operations (in a couple of apps I use JSON Serialization for 'blob' like document storage) this is also going to be handy.Performance?Some of you might be thinking that using dynamic and Reflection can't be good for performance. And you'd be right… In performing some informal testing it looks like the performance of the native code is nearly twice as fast as the dynamic code. Most of the slowness is attributable to type lookups. To test I created a native class that uses an actual reference to JSON.NET and performance was consistently around 85-90% faster with the referenced code. This will change though depending on the size of objects serialized - the larger the object the more processing time is spent inside the actual dynamically activated components and the less difference there will be. Dynamic code is always slower, but how much it really affects your application primarily depends on how frequently the dynamic code is called in relation to the non-dynamic code executing. In most situations where dynamic code is used 'to get the process rolling' as I do here the overhead is small enough to not matter.All that being said though - I serialized 10,000 objects in 80ms vs. 45ms so this is hardly slouchy performance. For the configuration component speed is not that important because both read and write operations typically happen once on first access and then every once in a while. But for other operations - say a serializer trying to handle AJAX requests on a Web Server one would be well served to create a hard dependency.Dynamic Loading - Worth it?Dynamic loading is not something you need to worry about but on occasion dynamic loading makes sense. But there's a price to be paid in added code  and a performance hit which depends on how frequently the dynamic code is accessed. But for some operations that are not pivotal to a component or application and are only used under certain circumstances dynamic loading can be beneficial to avoid having to ship extra files adding dependencies and loading down distributions. These days when you create new projects in Visual Studio with 30 assemblies before you even add your own code, trying to keep file counts under control seems like a good idea. It's not the kind of thing you do on a regular basis, but when needed it can be a useful option in your toolset… © Rick Strahl, West Wind Technologies, 2005-2013Posted in .NET  C#   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Nagging As A Strategy For Better Linking: -z guidance

  - by user9154181

  The link-editor (ld) in Solaris 11 has a new feature that we call guidance that is intended to help you build better objects. The basic idea behind guidance is that if (and only if) you request it, the link-editor will issue messages suggesting better options and other changes you might make to your ld command to get better results. You can choose to take the advice, or you can disable specific types of guidance while acting on others. In some ways, this works like an experienced friend leaning over your shoulder and giving you advice — you're free to take it or leave it as you see fit, but you get nudged to do a better job than you might have otherwise. We use guidance to build the core Solaris OS, and it has proven to be useful, both in improving our objects, and in making sure that regressions don't creep back in later. In this article, I'm going to describe the evolution in thinking and design that led to the implementation of the -z guidance option, as well as give a brief description of how it works. The guidance feature issues non-fatal warnings. However, experience shows that once developers get used to ignoring warnings, it is inevitable that real problems will be lost in the noise and ignored or missed. This is why we have a zero tolerance policy against build noise in the core Solaris OS. In order to get maximum benefit from -z guidance while maintaining this policy, I added the -z fatal-warnings option at the same time. Much of the material presented here is adapted from the arc case: PSARC 2010/312 Link-editor guidance The History Of Unfortunate Link-Editor Defaults The Solaris link-editor is one of the oldest Unix commands. It stands to reason that this would be true — in order to write an operating system, you need the ability to compile and link code. The original link-editor (ld) had defaults that made sense at the time. As new features were needed, command line option switches were added to let the user use them, while maintaining backward compatibility for those who didn't. Backward compatibility is always a concern in system design, but is particularly important in the case of the tool chain (compilers, linker, and related tools), since it is a basic building block for the entire system. Over the years, applications have grown in size and complexity. Important concepts like dynamic linking that didn't exist in the original Unix system were invented. Object file formats changed. In the case of System V Release 4 Unix derivatives like Solaris, the ELF (Extensible Linking Format) was adopted. Since then, the ELF system has evolved to provide tools needed to manage today's larger and more complex environments. Features such as lazy loading, and direct bindings have been added. In an ideal world, many of these options would be defaults, with rarely used options that allow the user to turn them off. However, the reality is exactly the reverse: For backward compatibility, these features are all options that must be explicitly turned on by the user. This has led to a situation in which most applications do not take advantage of the many improvements that have been made in linking over the last 20 years. If their code seems to link and run without issue, what motivation does a developer have to read a complex manpage, absorb the information provided, choose the features that matter for their application, and apply them? Experience shows that only the most motivated and diligent programmers will make that effort. We know that most programs would be improved if we could just get you to use the various whizzy features that we provide, but the defaults conspire against us. We have long wanted to do something to make it easier for our users to use the linkers more effectively. There have been many conversations over the years regarding this issue, and how to address it. They always break down along the following lines: Change ld Defaults Since the world would be a better place the newer ld features were the defaults, why not change things to make it so? This idea is simple, elegant, and impossible. Doing so would break a large number of existing applications, including those of ISVs, big customers, and a plethora of existing open source packages. In each case, the owner of that code may choose to follow our lead and fix their code, or they may view it as an invitation to reconsider their commitment to our platform. Backward compatibility, and our installed base of working software, is one of our greatest assets, and not something to be lightly put at risk. Breaking backward compatibility at this level of the system is likely to do more harm than good. But, it sure is tempting. New Link-Editor One might create a new linker command, not called 'ld', leaving the old command as it is. The new one could use the same code as ld, but would offer only modern options, with the proper defaults for features such as direct binding. The resulting link-editor would be a pleasure to use. However, the approach is doomed to niche status. There is a vast pile of exiting code in the world built around the existing ld command, that reaches back to the 1970's. ld use is embedded in large and unknown numbers of makefiles, and is used by name by compilers that execute it. A Unix link-editor that is not named ld will not find a majority audience no matter how good it might be. Finally, a new linker command will eventually cease to be new, and will accumulate its own burden of backward compatibility issues. An Option To Make ld Do The Right Things Automatically This line of reasoning is best summarized by a CR filed in 2005, entitled 6239804 make it easier for ld(1) to do what's best The idea is to have a '-z best' option that unchains ld from its backward compatibility commitment, and allows it to turn on the "best" set of features, as determined by the authors of ld. The specific set of features enabled by -z best would be subject to change over time, as requirements change. This idea is more realistic than the other two, but was never implemented because it has some important issues that we could never answer to our satisfaction: The -z best proposal assumes that the user can turn it on, and trust it to select good options without the user needing to be aware of the options being applied. This is a fallacy. Features such as direct bindings require the user to do some analysis to ensure that the resulting program will still operate properly. A user who is willing to do the work to verify that what -z best does will be OK for their application is capable of turning on those features directly, and therefore gains little added benefit from -z best. The intent is that when a user opts into -z best, that they understand that z best is subject to sometimes incompatible evolution. Experience teaches us that this won't work. People will use this feature, the meaning of -z best will change, code that used to build will fail, and then there will be complaints and demands to retract the change. When (not if) this occurs, we will of course defend our actions, and point at the disclaimer. We'll win some of those debates, and lose others. Ultimately, we'll end up with -z best2 (-z better), or other compromises, and our goal of simplifying the world will have failed. The -z best idea rolls up a set of features that may or may not be related to each other into a unit that must be taken wholesale, or not at all. It could be that only a subset of what it does is compatible with a given application, in which case the user is expected to abandon -z best and instead set the options that apply to their application directly. In doing so, they lose one of the benefits of -z best, that if you use it, future versions of ld may choose a different set of options, and automatically improve the object through the act of rebuilding it. I drew two conclusions from the above history: For a link-editor, backward compatibility is vital. If a given command line linked your application 10 years ago, you have every reason to expect that it will link today, assuming that the libraries you're linking against are still available and compatible with their previous interfaces. For an application of any size or complexity, there is no substitute for the work involved in examining the code and determining which linker options apply and which do not. These options are largely orthogonal to each other, and it can be reasonable not to use any or all of them, depending on the situation, even in modern applications. It is a mistake to tie them together. The idea for -z guidance came from consideration of these points. By decoupling the advice from the act of taking the advice, we can retain the good aspects of -z best while avoiding its pitfalls: -z guidance gives advice, but the decision to take that advice remains with the user who must evaluate its merit and make a decision to take it or not. As such, we are free to change the specific guidance given in future releases of ld, without breaking existing applications. The only fallout from this will be some new warnings in the build output, which can be ignored or dealt with at the user's convenience. It does not couple the various features given into a single "take it or leave it" option, meaning that there will never be a need to offer "-zguidance2", or other such variants as things change over time. Guidance has the potential to be our final word on this subject. The user is given the flexibility to disable specific categories of guidance without losing the benefit of others, including those that might be added to future versions of the system. Although -z fatal-warnings stands on its own as a useful feature, it is of particular interest in combination with -z guidance. Used together, the guidance turns from advice to hard requirement: The user must either make the suggested change, or explicitly reject the advice by specifying a guidance exception token, in order to get a build. This is valuable in environments with high coding standards. ld Command Line Options The guidance effort resulted in new link-editor options for guidance and for turning warnings into fatal errors. Before I reproduce that text here, I'd like to highlight the strategic decisions embedded in the guidance feature: In order to get guidance, you have to opt in. We hope you will opt in, and believe you'll get better objects if you do, but our default mode of operation will continue as it always has, with full backward compatibility, and without judgement. Guidance suggestions always offers specific advice, and not vague generalizations. You can disable some guidance without turning off the entire feature. When you get guidance warnings, you can choose to take the advice, or you can specify a keyword to disable guidance for just that category. This allows you to get guidance for things that are useful to you, without being bothered about things that you've already considered and dismissed. As the world changes, we will add new guidance to steer you in the right direction. All such new guidance will come with a keyword that let's you turn it off. In order to facilitate building your code on different versions of Solaris, we quietly ignore any guidance keywords we don't recognize, assuming that they are intended for newer versions of the link-editor. If you want to see what guidance tokens ld does and does not recognize on your system, you can use the ld debugging feature as follows: % ld -Dargs -z guidance=foo,nodefs debug: debug: Solaris Linkers: 5.11-1.2275 debug: debug: arg[1] option=-D: option-argument: args debug: arg[2] option=-z: option-argument: guidance=foo,nodefs debug: warning: unrecognized -z guidance item: foo The -z fatal-warning option is straightforward, and generally useful in environments with strict coding standards. Note that the GNU ld already had this feature, and we accept their option names as synonyms: -z fatal-warnings | nofatal-warnings --fatal-warnings | --no-fatal-warnings The -z fatal-warnings and the --fatal-warnings option cause the link-editor to treat warnings as fatal errors. The -z nofatal-warnings and the --no-fatal-warnings option cause the link-editor to treat warnings as non-fatal. This is the default behavior. The -z guidance option is defined as follows: -z guidance[=item1,item2,...] Provide guidance messages to suggest ld options that can improve the quality of the resulting object, or which are otherwise considered to be beneficial. The specific guidance offered is subject to change over time as the system evolves. Obsolete guidance offered by older versions of ld may be dropped in new versions. Similarly, new guidance may be added to new versions of ld. Guidance therefore always represents current best practices. It is possible to enable guidance, while preventing specific guidance messages, by providing a list of item tokens, representing the class of guidance to be suppressed. In this way, unwanted advice can be suppressed without losing the benefit of other guidance. Unrecognized item tokens are quietly ignored by ld, allowing a given ld command line to be executed on a variety of older or newer versions of Solaris. The guidance offered by the current version of ld, and the item tokens used to disable these messages, are as follows. Specify Required Dependencies Dynamic executables and shared objects should explicitly define all of the dependencies they require. Guidance recommends the use of the -z defs option, should any symbol references remain unsatisfied when building dynamic objects. This guidance can be disabled with -z guidance=nodefs. Do Not Specify Non-Required Dependencies Dynamic executables and shared objects should not define any dependencies that do not satisfy the symbol references made by the dynamic object. Guidance recommends that unused dependencies be removed. This guidance can be disabled with -z guidance=nounused. Lazy Loading Dependencies should be identified for lazy loading. Guidance recommends the use of the -z lazyload option should any dependency be processed before either a -z lazyload or -z nolazyload option is encountered. This guidance can be disabled with -z guidance=nolazyload. Direct Bindings Dependencies should be referenced with direct bindings. Guidance recommends the use of the -B direct, or -z direct options should any dependency be processed before either of these options, or the -z nodirect option is encountered. This guidance can be disabled with -z guidance=nodirect. Pure Text Segment Dynamic objects should not contain relocations to non-writable, allocable sections. Guidance recommends compiling objects with Position Independent Code (PIC) should any relocations against the text segment remain, and neither the -z textwarn or -z textoff options are encountered. This guidance can be disabled with -z guidance=notext. Mapfile Syntax All mapfiles should use the version 2 mapfile syntax. Guidance recommends the use of the version 2 syntax should any mapfiles be encountered that use the version 1 syntax. This guidance can be disabled with -z guidance=nomapfile. Library Search Path Inappropriate dependencies that are encountered by ld are quietly ignored. For example, a 32-bit dependency that is encountered when generating a 64-bit object is ignored. These dependencies can result from incorrect search path settings, such as supplying an incorrect -L option. Although benign, this dependency processing is wasteful, and might hide a build problem that should be solved. Guidance recommends the removal of any inappropriate dependencies. This guidance can be disabled with -z guidance=nolibpath. In addition, -z guidance=noall can be used to entirely disable the guidance feature. See Chapter 7, Link-Editor Quick Reference, in the Linker and Libraries Guide for more information on guidance and advice for building better objects. Example The following example demonstrates how the guidance feature is intended to work. We will build a shared object that has a variety of shortcomings: Does not specify all it's dependencies Specifies dependencies it does not use Does not use direct bindings Uses a version 1 mapfile Contains relocations to the readonly allocable text (not PIC) This scenario is sadly very common — many shared objects have one or more of these issues. % cat hello.c #include <stdio.h> #include <unistd.h> void hello(void) { printf("hello user %d\n", getpid()); } % cat mapfile.v1 # This version 1 mapfile will trigger a guidance message % cc hello.c -o hello.so -G -M mapfile.v1 -lelf As you can see, the operation completes without error, resulting in a usable object. However, turning on guidance reveals a number of things that could be better: % cc hello.c -o hello.so -G -M mapfile.v1 -lelf -zguidance ld: guidance: version 2 mapfile syntax recommended: mapfile.v1 ld: guidance: -z lazyload option recommended before first dependency ld: guidance: -B direct or -z direct option recommended before first dependency Undefined first referenced symbol in file getpid hello.o (symbol belongs to implicit dependency /lib/libc.so.1) printf hello.o (symbol belongs to implicit dependency /lib/libc.so.1) ld: warning: symbol referencing errors ld: guidance: -z defs option recommended for shared objects ld: guidance: removal of unused dependency recommended: libelf.so.1 warning: Text relocation remains referenced against symbol offset in file .rodata1 (section) 0xa hello.o getpid 0x4 hello.o printf 0xf hello.o ld: guidance: position independent (PIC) code recommended for shared objects ld: guidance: see ld(1) -z guidance for more information Given the explicit advice in the above guidance messages, it is relatively easy to modify the example to do the right things: % cat mapfile.v2 # This version 2 mapfile will not trigger a guidance message $mapfile_version 2 % cc hello.c -o hello.so -Kpic -G -Bdirect -M mapfile.v2 -lc -zguidance There are situations in which the guidance does not fit the object being built. For instance, you want to build an object without direct bindings: % cc -Kpic hello.c -o hello.so -G -M mapfile.v2 -lc -zguidance ld: guidance: -B direct or -z direct option recommended before first dependency ld: guidance: see ld(1) -z guidance for more information It is easy to disable that specific guidance warning without losing the overall benefit from allowing the remainder of the guidance feature to operate: % cc -Kpic hello.c -o hello.so -G -M mapfile.v2 -lc -zguidance=nodirect Conclusions The linking guidelines enforced by the ld guidance feature correspond rather directly to our standards for building the core Solaris OS. I'm sure that comes as no surprise. It only makes sense that we would want to build our own product as well as we know how. Solaris is usually the first significant test for any new linker feature. We now enable guidance by default for all builds, and the effect has been very positive. Guidance helps us find suboptimal objects more quickly. Programmers get concrete advice for what to change instead of vague generalities. Even in the cases where we override the guidance, the makefile rules to do so serve as documentation of the fact. Deciding to use guidance is likely to cause some up front work for most code, as it forces you to consider using new features such as direct bindings. Such investigation is worthwhile, but does not come for free. However, the guidance suggestions offer a structured and straightforward way to tackle modernizing your objects, and once that work is done, for keeping them that way. The investment is often worth it, and will replay you in terms of better performance and fewer problems. I hope that you find guidance to be as useful as we have.

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• I need help on my C++ assignment using MS Visual C++

  - by krayzwytie

  Ok, so I don't want you to do my homework for me, but I'm a little lost with this final assignment and need all the help I can get. Learning about programming is tough enough, but doing it online is next to impossible for me... Now, to get to the program, I am going to paste what I have so far. This includes mostly //comments and what I have written so far. If you can help me figure out where all the errors are and how to complete the assignment, I will really appreciate it. Like I said, I don't want you to do my homework for me (it's my final), but any constructive criticism is welcome. This is my final assignment for this class and it is due tomorrow (Sunday before midnight, Arizona time). This is the assignment: Examine the following situation: o Your company, Datamax, Inc., is in the process of automating its payroll systems. Your manager has asked you to create a program that calculates overtime pay for all employees. Your program must take into account the employee’s salary, total hours worked, and hours worked more than 40 in a week, and then provide an output that is useful and easily understood by company management. • Compile your program utilizing the following background information and the code outline in Appendix D (included in the code section). • Submit your project as an attachment including the code and the output. Company Background: o Three employees: Mark, John, and Mary o The end user needs to be prompted for three specific pieces of input—name, hours worked, and hourly wage. o Calculate overtime if input is greater than 40 hours per week. o Provide six test plans to verify the logic within the program. o Plan 1 must display the proper information for employee #1 with overtime pay. o Plan 2 must display the proper information for employee #1 with no overtime pay. o Plans 3-6 are duplicates of plan 1 and 2 but for the other employees. Program Requirements: o Define a base class to use for the entire program. o The class holds the function calls and the variables related to the overtime pay calculations. o Define one object per employee. Note there will be three employees. o Your program must take the objects created and implement calculations based on total salaries, total hours, and the total number of overtime hours. See the Employee Summary Data section of the sample output. Logic Steps to Complete Your Program: o Define your base class. o Define your objects from your base class. o Prompt for user input, updating your object classes for all three users. o Implement your overtime pay calculations. o Display overtime or regular time pay calculations. See the sample output below. o Implement object calculations by summarizing your employee objects and display the summary information in the example below. And this is the code: // Final_Project.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <iostream> #include <string> #include <iomanip> using namespace std; // //CLASS DECLARATION SECTION // class CEmployee { public: void ImplementCalculations(string EmployeeName, double hours, double wage); void DisplayEmployInformation(void); void Addsomethingup (CEmployee, CEmployee, CEmployee); string EmployeeName ; int hours ; int overtime_hours ; int iTotal_hours ; int iTotal_OvertimeHours ; float wage ; float basepay ; float overtime_pay ; float overtime_extra ; float iTotal_salaries ; float iIndividualSalary ; }; int main() { system("cls"); cout << "Welcome to the Employee Pay Center"; /* Use this section to define your objects. You will have one object per employee. You have only three employees. The format is your class name and your object name. */ std::cout << "Please enter Employee's Name: "; std::cin >> EmployeeName; std::cout << "Please enter Total Hours for (EmployeeName): "; std::cin >> hours; std::cout << "Please enter Base Pay for(EmployeeName): "; std::cin >> basepay; /* Here you will prompt for the first employee’s information. Prompt the employee name, hours worked, and the hourly wage. For each piece of information, you will update the appropriate class member defined above. Example of Prompts Enter the employee name = Enter the hours worked = Enter his or her hourly wage = */ /* Here you will prompt for the second employee’s information. Prompt the employee name, hours worked, and the hourly wage. For each piece of information, you will update the appropriate class member defined above. Enter the employee name = Enter the hours worked = Enter his or her hourly wage = */ /* Here you will prompt for the third employee’s information. Prompt the employee name, hours worked, and the hourly wage. For each piece of information, you will update the appropriate class member defined above. Enter the employee name = Enter the hours worked = Enter his or her hourly wage = */ /* Here you will implement a function call to implement the employ calcuations for each object defined above. You will do this for each of the three employees or objects. The format for this step is the following: [(object name.function name(objectname.name, objectname.hours, objectname.wage)] ; */ /* This section you will send all three objects to a function that will add up the the following information: - Total Employee Salaries - Total Employee Hours - Total Overtime Hours The format for this function is the following: - Define a new object. - Implement function call [objectname.functionname(object name 1, object name 2, object name 3)] /* } //End of Main Function void CEmployee::ImplementCalculations (string EmployeeName, double hours, double wage){ //Initialize overtime variables overtime_hours=0; overtime_pay=0; overtime_extra=0; if (hours > 40) { /* This section is for the basic calculations for calculating overtime pay. - base pay = 40 hours times the hourly wage - overtime hours = hours worked – 40 - overtime pay = hourly wage * 1.5 - overtime extra pay over 40 = overtime hours * overtime pay - salary = overtime money over 40 hours + your base pay */ /* Implement function call to output the employee information. Function is defined below. */ } // if (hours > 40) else { /* Here you are going to calculate the hours less than 40 hours. - Your base pay is = your hours worked times your wage - Salary = your base pay */ /* Implement function call to output the employee information. Function is defined below. */ } // End of the else } //End of Primary Function void CEmployee::DisplayEmployInformation(); { // This function displays all the employee output information. /* This is your cout statements to display the employee information: Employee Name ............. = Base Pay .................. = Hours in Overtime ......... = Overtime Pay Amount........ = Total Pay ................. = */ } // END OF Display Employee Information void CEmployee::Addsomethingup (CEmployee Employ1, CEmployee Employ2) { // Adds two objects of class Employee passed as // function arguments and saves them as the calling object's data member values. /* Add the total hours for objects 1, 2, and 3. Add the salaries for each object. Add the total overtime hours. */ /* Then display the information below. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%% EMPLOYEE SUMMARY DATA%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%% Total Employee Salaries ..... = 576.43 %%%% Total Employee Hours ........ = 108 %%%% Total Overtime Hours......... = 5 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% */ } // End of function

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• Primefaces datatable in-cell edit to update other rows in the same datatable with ajax rowEdit event processing

  - by Java Thu

  I have issue to update other rows in the same datatable when one row updated using primeface datatable in-cell edit ajax rowEdit. But failed to update other row with ajax call. The ajax response only return the same row data which was updated. The codes are as following: <h:form id="testForm"> <p:dataTable id="testDT" var="d" rowIndexVar="rowIndex" value="#{testBean.lists}" editable="true"> <p:column> <f:facet name="header">No</f:facet> <h:outputText value="#{rowIndex}" /> </p:column> <p:column headerText="Value"> <p:cellEditor> <f:facet name="output"> <h:outputText value="#{d.value}" /> </f:facet> <f:facet name="input"> <p:inputText value="#{d.value}" size="5" /> </f:facet> </p:cellEditor> </p:column> <p:column headerText="Edit" style="width:50px"> <p:outputPanel rendered="#{d.editable}"> <p:rowEditor> </p:rowEditor> </p:outputPanel> </p:column> <p:ajax event="rowEdit" update=":testForm:testDT" listener="#{testBean.onRowUpdate}" /> </p:dataTable> </h:form> My TestBean: package web.bean.test; import java.util.ArrayList; import java.util.List; import javax.annotation.PostConstruct; import javax.faces.bean.ManagedBean; import javax.faces.bean.ViewScoped; import org.primefaces.event.RowEditEvent; @ManagedBean(name="testBean") @ViewScoped public class TestBean { private List<TestData> lists = new ArrayList<>(); @PostConstruct protected void init() { TestData d = new TestData("Row1Data", 1d, true); lists.add(d); d = new TestData("Row1Data", 11.11d, false); lists.add(d); } public void onRowUpdate(RowEditEvent event) { Object o = event.getObject(); if (o != null) { TestData d = (TestData)o; TestData d1 = lists.get(1); d1.setValue(d1.getValue() + d.getValue()); } } public List<TestData> getLists() { return lists; } public void setLists(List<TestData> lists) { this.lists = lists; } } package web.bean.test; public class TestData { private String name; private double value; private boolean editable; public TestData(String name, double value, boolean editable) { super(); this.name = name; this.value = value; this.editable = editable; } public TestData() { } public String getName() { return name; } public void setName(String name) { this.name = name; } public double getValue() { return value; } public void setValue(double value) { this.value = value; } public boolean isEditable() { return editable; } public void setEditable(boolean editable) { this.editable = editable; } } The ajax response body: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"><head><link type="text/css" rel="stylesheet" href="/Octopus-G/javax.faces.resource/theme.css.xhtml?ln=primefaces-bluesky" /><link type="text/css" rel="stylesheet" href="/Octopus-G/javax.faces.resource/primefaces.css.xhtml?ln=primefaces&amp;v=3.2" /><script type="text/javascript" src="/Octopus-G/javax.faces.resource/jquery/jquery.js.xhtml?ln=primefaces&amp;v=3.2"></script><script type="text/javascript" src="/Octopus-G/javax.faces.resource/primefaces.js.xhtml?ln=primefaces&amp;v=3.2"></script></head><body> <form id="testForm" name="testForm" method="post" action="/Octopus-G/test.xhtml" enctype="application/x-www-form-urlencoded"> <input type="hidden" name="testForm" value="testForm" /> <div id="testForm:testDT" class="ui-datatable ui-widget"><table role="grid"><thead><tr role="row"><th id="testForm:testDT:j_idt5" class="ui-state-default" role="columnheader"><div class="ui-dt-c"><span>No</span></div></th><th id="testForm:testDT:j_idt8" class="ui-state-default" role="columnheader"><div class="ui-dt-c"><span>Value</span></div></th><th id="testForm:testDT:j_idt12" class="ui-state-default" role="columnheader" style="width:50px"><div class="ui-dt-c"><span>Edit</span></div></th></tr></thead><tfoot></tfoot><tbody id="testForm:testDT_data" class="ui-datatable-data ui-widget-content"><tr data-ri="0" class="ui-widget-content ui-datatable-even" role="row"><td role="gridcell"><div class="ui-dt-c">0</div></td><td role="gridcell" class="ui-editable-column"><div class="ui-dt-c"><span id="testForm:testDT:0:j_idt9" class="ui-cell-editor"><span class="ui-cell-editor-output">1.0</span><span class="ui-cell-editor-input"><input id="testForm:testDT:0:j_idt11" name="testForm:testDT:0:j_idt11" type="text" value="1.0" size="5" class="ui-inputfield ui-inputtext ui-widget ui-state-default ui-corner-all" /><script id="testForm:testDT:0:j_idt11_s" type="text/javascript">PrimeFaces.cw('InputText','widget_testForm_testDT_0_j_idt11',{id:'testForm:testDT:0:j_idt11'});</script></span></span></div></td><td role="gridcell" style="width:50px"><div class="ui-dt-c"><span id="testForm:testDT:0:j_idt13"><span id="testForm:testDT:0:j_idt14" class="ui-row-editor"><span class="ui-icon ui-icon-pencil"></span><span class="ui-icon ui-icon-check" style="display:none"></span><span class="ui-icon ui-icon-close" style="display:none"></span></span></span></div></td></tr><tr data-ri="1" class="ui-widget-content ui-datatable-odd" role="row"><td role="gridcell"><div class="ui-dt-c">1</div></td><td role="gridcell" class="ui-editable-column"><div class="ui-dt-c"><span id="testForm:testDT:1:j_idt9" class="ui-cell-editor"><span class="ui-cell-editor-output">11.11</span><span class="ui-cell-editor-input"><input id="testForm:testDT:1:j_idt11" name="testForm:testDT:1:j_idt11" type="text" value="11.11" size="5" class="ui-inputfield ui-inputtext ui-widget ui-state-default ui-corner-all" /><script id="testForm:testDT:1:j_idt11_s" type="text/javascript">PrimeFaces.cw('InputText','widget_testForm_testDT_1_j_idt11',{id:'testForm:testDT:1:j_idt11'});</script></span></span></div></td><td role="gridcell" style="width:50px"><div class="ui-dt-c"></div></td></tr></tbody></table></div><script id="testForm:testDT_s" type="text/javascript">$(function() {PrimeFaces.cw('DataTable','widget_testForm_testDT',{id:'testForm:testDT',editable:true,behaviors:{rowEdit:function(event) {PrimeFaces.ab({source:'testForm:testDT',process:'testForm:testDT',update:'testForm:testDT',event:'rowEdit'}, arguments[1]);}}});});</script><input type="hidden" name="javax.faces.ViewState" id="javax.faces.ViewState" value="-8223787210091934199:-360328890338571623" autocomplete="off" /> </form></body> </html>

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• ControlTemplate Exception: "XamlParseException: Cannot find a Resource with the Name/Key"

  - by akaphenom

  If I move the application resources to a UserControl resources everythgin runs groovy. I still don't understand why. I noticed that my application object MyApp did more than inherit from Application it loaded an XAML for the main template and connected all the plumbing. So I decided to create a user control to remove the template from the applciation (thinking there may be an even order issue not allowing my resource to be found). namespace Module1 type Template() as this = //inherit UriUserControl("/FSSilverlightApp;component/template.xaml", "") inherit UriUserControl("/FSSilverlightApp;component/templateSimple.xaml", "") do Application.LoadComponent(this, base.uri) let siteTemplate : Grid = (this.Content :?> FrameworkElement) ? siteTemplate let nav : Frame = siteTemplate ? contentFrame let pages : UriUserControl array = [| new Module1.Page1() :> UriUserControl ; new Module1.Page2() :> UriUserControl ; new Module1.Page3() :> UriUserControl ; new Module1.Page4() :> UriUserControl ; new Module1.Page5() :> UriUserControl ; |] do nav.Navigate((pages.[0] :> INamedUriProvider).Uri) |> ignore type MyApp() as this = inherit Application() do Application.LoadComponent(this, new System.Uri("/FSSilverlightApp;component/App.xaml", System.UriKind.Relative)) do System.Windows.Browser.HtmlPage.Plugin.Focus() this.RootVisual <- new Template() ; // test code to check for the existance of the ControlTemplate - it exists let a = Application.Current.Resources.MergedDictionaries let b = a.[0] let c = b.Count let d : ControlTemplate = downcast c.["TransitioningFrame"] () "/FSSilverlightApp;component/templateSimple.xaml" <UserControl x:Class="Module1.Template" xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" > <Grid HorizontalAlignment="Center" Background="White" Name="siteTemplate"> <StackPanel Grid.Row="3" Grid.Column="2" Name="mainPanel"> <!--Template="{StaticResource TransitioningFrame}"--> <navigation:Frame Name="contentFrame" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Template="{StaticResource TransitioningFrame}"/> </StackPanel> </Grid> </UserControl> "/FSSilverlightApp;component/App.xaml" <Application xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="Module1.MyApp"> <Application.Resources> <ResourceDictionary> <ResourceDictionary.MergedDictionaries> <ResourceDictionary Source="/FSSilverlightApp;component/TransitioningFrame.xaml" /> </ResourceDictionary.MergedDictionaries> </ResourceDictionary> </Application.Resources> </Application> "/FSSilverlightApp;component/TransitioningFrame.xaml" <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"> <ControlTemplate x:Key="TransitioningFrame" TargetType="navigation:Frame"> <Border Background="Olive" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="5" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"> <ContentPresenter Cursor="{TemplateBinding Cursor}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}" Content="{TemplateBinding Content}"/> </Border> </ControlTemplate> </ResourceDictionary> Unfortunately that did not work. If I remove the template attribute from the navigationFrame element, the app loads and directs the content area to the first page in the pages array. Referencing that resource continues to throw a resource no found error. Original Post I have the following app.xaml (using Silverlight 3) <Application xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="Module1.MyApp"> <Application.Resources> <ResourceDictionary> <ResourceDictionary.MergedDictionaries> <ResourceDictionary Source="/FSSilverlightApp;component/TransitioningFrame.xaml" /> </ResourceDictionary.MergedDictionaries> </ResourceDictionary> </Application.Resources> </Application> and content template: <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"> <ControlTemplate x:Key="TransitioningFrame" TargetType="navigation:Frame"> <Border Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"> <ContentPresenter Cursor="{TemplateBinding Cursor}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}" Content="{TemplateBinding Content}"/> </Border> </ControlTemplate> </ResourceDictionary> The debugger says it the contentTemplate is loaded correctly by adding some minimal code: type MyApp() as this = inherit Application() do Application.LoadComponent(this, new System.Uri("/FSSilverlightApp;component/App.xaml", System.UriKind.Relative)) let cc = new ContentControl() let mainGrid : Grid = loadXaml("MainWindow.xaml") do this.Startup.Add(this.startup) let t = Application.Current.Resources.MergedDictionaries let t1 = t.[0] let t2 = t1.Count let t3: ControlTemplate = t1.["TransitioningFrame"] With this line in my main.xaml <navigation:Frame Name="contentFrame" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Template="{StaticResource TransitioningFrame}"/> Yields this exception Webpage error details User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; InfoPath.2; .NET4.0C; .NET4.0E) Timestamp: Mon, 24 May 2010 23:10:15 UTC Message: Unhandled Error in Silverlight Application Code: 4004 Category: ManagedRuntimeError Message: System.Windows.Markup.XamlParseException: Cannot find a Resource with the Name/Key TransitioningFrame [Line: 86 Position: 115] at MS.Internal.XcpImports.CreateFromXaml(String xamlString, Boolean createNamescope, Boolean requireDefaultNamespace, Boolean allowEventHandlers, Boolean expandTemplatesDuringParse) at MS.Internal.XcpImports.CreateFromXaml(String xamlString, Boolean createNamescope, Boolean requireDefaultNamespace, Boolean allowEventHandlers) at System.Windows.Markup.XamlReader.Load(String xaml) at Globals.loadXaml[T](String xamlPath) at Module1.MyApp..ctor() Line: 54 Char: 13 Code: 0 URI: file:///C:/fsharp/FSSilverlightDemo/FSSilverlightApp/bin/Debug/SilverlightApplication2TestPage.html

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• How do I set the encoding statement in the XML declaration when performing an XSL transformation usi

  - by aspiehler

  I wrote a simple package installer in WinBatch that needs to update an XML file with information about the package contents. My first stab at it involved loading the file with Msxml2.DOMDocument, adding nodes and data as required, then saving the data back to disk. This worked well enough, except that it would not create tab and CR/LF whitespace in the new data. The solution I came up with was writing an XSL stylesheet that would recreate the XML file with whitespace added back in. I'm doing this by: loading the XSL file into an Msxml2.FreeThreadedDOMDocument object setting that object as the stylesheet property of an Msxml2.XSLTemplate object creating an XSL processor via Msxml2.XSLTemplate.createProcessor() setting my original Msxml2.DOMDocument as the input property of the XSL processor Calling transform() method of the XSL processor, and saving the output to a file. This works as for as reformatting the XML file with tabs and carriage returns, but my XML declaration comes out either as <?xml version="1.0"?> or <?xml version="1.0" encoding="UTF-16"?> depending on whether I used Msxml2.*.6.0 or Msxml2.* objects (a fall back if the system doesn't have 6.0). If the encoding is set to UTF-16, Msxml12.DOMDocument complains about trying to convert UTF-16 to 1-byte encoding the next time I run my package installer. I've tried creating and adding an XML declaration using both createProcessingInstruction() to both the XML and XSL DOM objects, but neither one seems to affect the output of the XSLTemplate processor. I've also set encoding to UTF-8 in the <xsl:output/> tag in my XSL file. Here is the relevant code in my Winbatch script: xmlDoc = ObjectCreate("Msxml2.DOMDocument.6.0") if !xmlDoc then xmlDoc = ObjectCreate("Msxml2.DOMDocument") xmlDoc.async = @FALSE xmlDoc.validateOnParse = @TRUE xmlDoc.resolveExternals = @TRUE xmlDoc.preserveWhiteSpace = @TRUE xmlDoc.setProperty("SelectionLanguge", "XPath") xmlDoc.setProperty("SelectionNamespaces", "xmlns:fns='http://www.abc.com/f_namespace'") xmlDoc.load(xml_file_path) xslStyleSheet = ObjectCreate("Msxml2.FreeThreadedDOMDocument.6.0") if !xslStyleSheet then xslStyleSheet = ObjectCreate("Msxml2.FreeThreadedDOMDocument") xslStyleSheet.async = @FALSE xslStyleSheet.validateOnParse = @TRUE xslStyleSheet.load(xsl_style_sheet_path) xslTemplate = ObjectCreate("Msxml2.XSLTemplate.6.0") if !xslTemplate then xslTemplate = ObjectCreate("Msxml2.XSLTemplate") xslTemplate.stylesheet = xslStyleSheet processor = xslTemplate.createProcessor() processor.input = xmlDoc processor.transform() ; create a new file and write the XML processor output to it fh = FileOpen(output_file_path, "WRITE" , @FALSE) FileWrite(fh, processor.output) FileClose(fh) The style sheet, with some slight changes to protect the innocent: <?xml version="1.0" encoding="UTF-8"?> <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.1"> <xsl:output method="xml" indent="yes" encoding="UTF-8"/> <xsl:template match="/"> <fns:test_station xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:fns="http://www.abc.com/f_namespace"> <xsl:for-each select="/fns:test_station/identification"> <xsl:text>&#x0A; </xsl:text> <identification> <xsl:for-each select="./*"> <xsl:text>&#x0A; </xsl:text> <xsl:copy-of select="."/> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </identification> </xsl:for-each> <xsl:for-each select="/fns:test_station/software"> <xsl:text>&#x0A; </xsl:text> <software> <xsl:for-each select="./package"> <xsl:text>&#x0A; </xsl:text> <package> <xsl:for-each select="./*"> <xsl:text>&#x0A; </xsl:text> <xsl:copy-of select="."/> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </package> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </software> </xsl:for-each> <xsl:for-each select="/fns:test_station/calibration"> <xsl:text>&#x0A; </xsl:text> <calibration> <xsl:for-each select="./item"> <xsl:text>&#x0A; </xsl:text> <item> <xsl:for-each select="./*"> <xsl:text>&#x0A; </xsl:text> <xsl:copy-of select="."/> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </item> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </calibration> </xsl:for-each> </fns:test_station> </xsl:template> </xsl:stylesheet> And this is a sample output file: <?xml version="1.0" encoding="UTF-16"?> <fns:test_station xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:fns="http://www.abc.com/f_namespace"> <software> <package> <part_number>123456789</part_number> <version>00</version> <test_category>1</test_category> <description>name of software package</description> <execution_path>c:\program files\test\test.exe</execution_path> <execution_arguments>arguments</execution_arguments> <crc_path>c:\ste_config\crc\123456789.lst</crc_path> <uninstall_path>c:\ste_config\uninstall\uninst_123456789.bat</uninstall_path> <install_timestamp>2009-11-09T14:00:44</install_timestamp> </package> </software> </fns:test_station>

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