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• We've completed the first iteration

  - by CliveT

  There are a lot of features in C# that are implemented by the compiler and not by the underlying platform. One such feature is a lambda expression. Since local variables cannot be accessed once the current method activation finishes, the compiler has to go out of its way to generate a new class which acts as a home for any variable whose lifetime needs to be extended past the activation of the procedure. Take the following example:     Random generator = new Random();     Func func = () = generator.Next(10); In this case, the compiler generates a new class called c_DisplayClass1 which is marked with the CompilerGenerated attribute. [CompilerGenerated] private sealed class c__DisplayClass1 {     // Fields     public Random generator;     // Methods     public int b__0()     {         return this.generator.Next(10);     } } Two quick comments on this: (i)    A display was the means that compilers for languages like Algol recorded the various lexical contours of the nested procedure activations on the stack. I imagine that this is what has led to the name. (ii)    It is a shame that the same attribute is used to mark all compiler generated classes as it makes it hard to figure out what they are being used for. Indeed, you could imagine optimisations that the runtime could perform if it knew that classes corresponded to certain high level concepts. We can see that the local variable generator has been turned into a field in the class, and the body of the lambda expression has been turned into a method of the new class. The code that builds the Func object simply constructs an instance of this class and initialises the fields to their initial values.     c__DisplayClass1 class2 = new c__DisplayClass1();     class2.generator = new Random();     Func func = new Func(class2.b__0); Reflector already contains code to spot this pattern of code and reproduce the form containing the lambda expression, so this is example is correctly decompiled. The use of compiler generated code is even more spectacular in the case of iterators. C# introduced the idea of a method that could automatically store its state between calls, so that it can pick up where it left off. The code can express the logical flow with yield return and yield break denoting places where the method should return a particular value and be prepared to resume.         {             yield return 1;             yield return 2;             yield return 3;         } Of course, there was already a .NET pattern for expressing the idea of returning a sequence of values with the computation proceeding lazily (in the sense that the work for the next value is executed on demand). This is expressed by the IEnumerable interface with its Current property for fetching the current value and the MoveNext method for forcing the computation of the next value. The sequence is terminated when this method returns false. The C# compiler links these two ideas together so that an IEnumerator returning method using the yield keyword causes the compiler to produce the implementation of an Iterator. Take the following piece of code.         IEnumerable GetItems()         {             yield return 1;             yield return 2;             yield return 3;         } The compiler implements this by defining a new class that implements a state machine. This has an integer state that records which yield point we should go to if we are resumed. It also has a field that records the Current value of the enumerator and a field for recording the thread. This latter value is used for optimising the creation of iterator instances. [CompilerGenerated] private sealed class d__0 : IEnumerable, IEnumerable, IEnumerator, IEnumerator, IDisposable {     // Fields     private int 1__state;     private int 2__current;     public Program 4__this;     private int l__initialThreadId; The body gets converted into the code to construct and initialize this new class. private IEnumerable GetItems() {     d__0 d__ = new d__0(-2);     d__.4__this = this;     return d__; } When the class is constructed we set the state, which was passed through as -2 and the current thread. public d__0(int 1__state) {     this.1__state = 1__state;     this.l__initialThreadId = Thread.CurrentThread.ManagedThreadId; } The state needs to be set to 0 to represent a valid enumerator and this is done in the GetEnumerator method which optimises for the usual case where the returned enumerator is only used once. IEnumerator IEnumerable.GetEnumerator() {     if ((Thread.CurrentThread.ManagedThreadId == this.l__initialThreadId)               && (this.1__state == -2))     {         this.1__state = 0;         return this;     } The state machine itself is implemented inside the MoveNext method. private bool MoveNext() {     switch (this.1__state)     {         case 0:             this.1__state = -1;             this.2__current = 1;             this.1__state = 1;             return true;         case 1:             this.1__state = -1;             this.2__current = 2;             this.1__state = 2;             return true;         case 2:             this.1__state = -1;             this.2__current = 3;             this.1__state = 3;             return true;         case 3:             this.1__state = -1;             break;     }     return false; } At each stage, the current value of the state is used to determine how far we got, and then we generate the next value which we return after recording the next state. Finally we return false from the MoveNext to signify the end of the sequence. Of course, that example was really simple. The original method body didn't have any local variables. Any local variables need to live between the calls to MoveNext and so they need to be transformed into fields in much the same way that we did in the case of the lambda expression. More complicated MoveNext methods are required to deal with resources that need to be disposed when the iterator finishes, and sometimes the compiler uses a temporary variable to hold the return value. Why all of this explanation? We've implemented the de-compilation of iterators in the current EAP version of Reflector (7). This contrasts with previous version where all you could do was look at the MoveNext method and try to figure out the control flow. There's a fair amount of things we have to do. We have to spot the use of a CompilerGenerated class which implements the Enumerator pattern. We need to go to the class and figure out the fields corresponding to the local variables. We then need to go to the MoveNext method and try to break it into the various possible states and spot the state transitions. We can then take these pieces and put them back together into an object model that uses yield return to show the transition points. After that Reflector can carry on optimising using its usual optimisations. The pattern matching is currently a little too sensitive to changes in the code generation, and we only do a limited analysis of the MoveNext method to determine use of the compiler generated fields. In some ways, it is a pity that iterators are compiled away and there is no metadata that reflects the original intent. Without it, we are always going to dependent on our knowledge of the compiler's implementation. For example, we have noticed that the Async CTP changes the way that iterators are code generated, so we'll have to do some more work to support that. However, with that warning in place, we seem to do a reasonable job of decompiling the iterators that are built into the framework. Hopefully, the EAP will give us a chance to find examples where we don't spot the pattern correctly or regenerate the wrong code, and we can improve things. Please give it a go, and report any problems.

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• PostSharp, Obfuscation, and IL

  - by simonc

  Aspect-oriented programming (AOP) is a relatively new programming paradigm. Originating at Xerox PARC in 1994, the paradigm was first made available for general-purpose development as an extension to Java in 2001. From there, it has quickly been adapted for use in all the common languages used today. In the .NET world, one of the primary AOP toolkits is PostSharp. Attributes and AOP Normally, attributes in .NET are entirely a metadata construct. Apart from a few special attributes in the .NET framework, they have no effect whatsoever on how a class or method executes within the CLR. Only by using reflection at runtime can you access any attributes declared on a type or type member. PostSharp changes this. By declaring a custom attribute that derives from PostSharp.Aspects.Aspect, applying it to types and type members, and running the resulting assembly through the PostSharp postprocessor, you can essentially declare 'clever' attributes that change the behaviour of whatever the aspect has been applied to at runtime. A simple example of this is logging. By declaring a TraceAttribute that derives from OnMethodBoundaryAspect, you can automatically log when a method has been executed: public class TraceAttribute : PostSharp.Aspects.OnMethodBoundaryAspect { public override void OnEntry(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Entering {0}.{1}.", method.DeclaringType.FullName, method.Name)); } public override void OnExit(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Leaving {0}.{1}.", method.DeclaringType.FullName, method.Name)); } } [Trace] public void MethodToLog() { ... } Now, whenever MethodToLog is executed, the aspect will automatically log entry and exit, without having to add the logging code to MethodToLog itself. PostSharp Performance Now this does introduce a performance overhead - as you can see, the aspect allows access to the MethodBase of the method the aspect has been applied to. If you were limited to C#, you would be forced to retrieve each MethodBase instance using Type.GetMethod(), matching on the method name and signature. This is slow. Fortunately, PostSharp is not limited to C#. It can use any instruction available in IL. And in IL, you can do some very neat things. Ldtoken C# allows you to get the Type object corresponding to a specific type name using the typeof operator: Type t = typeof(Random); The C# compiler compiles this operator to the following IL: ldtoken [mscorlib]System.Random call class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle( valuetype [mscorlib]System.RuntimeTypeHandle) The ldtoken instruction obtains a special handle to a type called a RuntimeTypeHandle, and from that, the Type object can be obtained using GetTypeFromHandle. These are both relatively fast operations - no string lookup is required, only direct assembly and CLR constructs are used. However, a little-known feature is that ldtoken is not just limited to types; it can also get information on methods and fields, encapsulated in a RuntimeMethodHandle or RuntimeFieldHandle: // get a MethodBase for String.EndsWith(string) ldtoken method instance bool [mscorlib]System.String::EndsWith(string) call class [mscorlib]System.Reflection.MethodBase [mscorlib]System.Reflection.MethodBase::GetMethodFromHandle( valuetype [mscorlib]System.RuntimeMethodHandle) // get a FieldInfo for the String.Empty field ldtoken field string [mscorlib]System.String::Empty call class [mscorlib]System.Reflection.FieldInfo [mscorlib]System.Reflection.FieldInfo::GetFieldFromHandle( valuetype [mscorlib]System.RuntimeFieldHandle) These usages of ldtoken aren't usable from C# or VB, and aren't likely to be added anytime soon (Eric Lippert's done a blog post on the possibility of adding infoof, methodof or fieldof operators to C#). However, PostSharp deals directly with IL, and so can use ldtoken to get MethodBase objects quickly and cheaply, without having to resort to string lookups. The kicker However, there are problems. Because ldtoken for methods or fields isn't accessible from C# or VB, it hasn't been as well-tested as ldtoken for types. This has resulted in various obscure bugs in most versions of the CLR when dealing with ldtoken and methods, and specifically, generic methods and methods of generic types. This means that PostSharp was behaving incorrectly, or just plain crashing, when aspects were applied to methods that were generic in some way. So, PostSharp has to work around this. Without using the metadata tokens directly, the only way to get the MethodBase of generic methods is to use reflection: Type.GetMethod(), passing in the method name as a string along with information on the signature. Now, this works fine. It's slower than using ldtoken directly, but it works, and this only has to be done for generic methods. Unfortunately, this poses problems when the assembly is obfuscated. PostSharp and Obfuscation When using ldtoken, obfuscators don't affect how PostSharp operates. Because the ldtoken instruction directly references the type, method or field within the assembly, it is unaffected if the name of the object is changed by an obfuscator. However, the indirect loading used for generic methods was breaking, because that uses the name of the method when the assembly is put through the PostSharp postprocessor to lookup the MethodBase at runtime. If the name then changes, PostSharp can't find it anymore, and the assembly breaks. So, PostSharp needs to know about any changes an obfuscator does to an assembly. The way PostSharp does this is by adding another layer of indirection. When PostSharp obfuscation support is enabled, it includes an extra 'name table' resource in the assembly, consisting of a series of method & type names. When PostSharp needs to lookup a method using reflection, instead of encoding the method name directly, it looks up the method name at a fixed offset inside that name table: MethodBase genericMethod = typeof(ContainingClass).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: get_Prop1 21: set_Prop1 22: DoFoo 23: GetWibble When the assembly is later processed by an obfuscator, the obfuscator can replace all the method and type names within the name table with their new name. That way, the reflection lookups performed by PostSharp will now use the new names, and everything will work as expected: MethodBase genericMethod = typeof(#kGy).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: #kkA 21: #zAb 22: #EF5a 23: #2tg As you can see, this requires direct support by an obfuscator in order to perform these rewrites. Dotfuscator supports it, and now, starting with SmartAssembly 6.6.4, SmartAssembly does too. So, a relatively simple solution to a tricky problem, with some CLR bugs thrown in for good measure. You don't see those every day! Cross posted from Simple Talk.

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• Super constructor must be a first statement in Java constructor [closed]

  - by Val

  I know the answer: "we need rules to prevent shooting into your own foot". Ok, I make millions of programming mistakes every day. To be prevented, we need one simple rule: prohibit all JLS and do not use Java. If we explain everything by "not shooting your foot", this is reasonable. But there is not much reason is such reason. When I programmed in Delphy, I always wanted the compiler to check me if I read uninitializable. I have discovered myself that is is stupid to read uncertain variable because it leads unpredictable result and is errorenous obviously. By just looking at the code I could see if there is an error. I wished if compiler could do this job. It is also a reliable signal of programming error if function does not return any value. But I never wanted it do enforce me the super constructor first. Why? You say that constructors just initialize fields. Super fields are derived; extra fields are introduced. From the goal point of view, it does not matter in which order you initialize the variables. I have studied parallel architectures and can say that all the fields can even be assigned in parallel... What? Do you want to use the unitialized fields? Stupid people always want to take away our freedoms and break the JLS rules the God gives to us! Please, policeman, take away that person! Where do I say so? I'm just saying only about initializing/assigning, not using the fields. Java compiler already defends me from the mistake of accessing notinitialized. Some cases sneak but this example shows how this stupid rule does not save us from the read-accessing incompletely initialized in construction: public class BadSuper { String field; public String toString() { return "field = " + field; } public BadSuper(String val) { field = val; // yea, superfirst does not protect from accessing // inconstructed subclass fields. Subclass constr // must be called before super()! System.err.println(this); } } public class BadPost extends BadSuper { Object o; public BadPost(Object o) { super("str"); this. o = o; } public String toString() { // superconstructor will boom here, because o is not initialized! return super.toString() + ", obj = " + o.toString(); } public static void main(String[] args) { new BadSuper("test 1"); new BadPost(new Object()); } } It shows that actually, subfields have to be inilialized before the supreclass! Meantime, java requirement "saves" us from writing specializing the class by specializing what the super constructor argument is, public class MyKryo extends Kryo { class MyClassResolver extends DefaultClassResolver { public Registration register(Registration registration) { System.out.println(MyKryo.this.getDepth()); return super.register(registration); } } MyKryo() { // cannot instantiate MyClassResolver in super super(new MyClassResolver(), new MapReferenceResolver()); } } Try to make it compilable. It is always pain. Especially, when you cannot assign the argument later. Initialization order is not important for initialization in general. I could understand that you should not use super methods before initializing super. But, the requirement for super to be the first statement is different. It only saves you from the code that does useful things simply. I do not see how this adds safety. Actually, safety is degraded because we need to use ugly workarounds. Doing post-initialization, outside the constructors also degrades safety (otherwise, why do we need constructors?) and defeats the java final safety reenforcer. To conclude Reading not initialized is a bug. Initialization order is not important from the computer science point of view. Doing initalization or computations in different order is not a bug. Reenforcing read-access to not initialized is good but compilers fail to detect all such bugs Making super the first does not solve the problem as it "Prevents" shooting into right things but not into the foot It requires to invent workarounds, where, because of complexity of analysis, it is easier to shoot into the foot doing post-initialization outside the constructors degrades safety (otherwise, why do we need constructors?) and that degrade safety by defeating final access modifier When there was java forum alive, java bigots attecked me for these thoughts. Particularly, they dislaked that fields can be initialized in parallel, saying that natural development ensures correctness. When I replied that you could use an advanced engineering to create a human right away, without "developing" any ape first, and it still be an ape, they stopped to listen me. Cos modern technology cannot afford it. Ok, Take something simpler. How do you produce a Renault? Should you construct an Automobile first? No, you start by producing a Renault and, once completed, you'll see that this is an automobile. So, the requirement to produce fields in "natural order" is unnatural. In case of alarmclock or armchair, which are still chair and clock, you may need first develop the base (clock and chair) and then add extra. So, I can have examples where superfields must be initialized first and, oppositely, when they need to be initialized later. The order does not exist in advance. So, the compiler cannot be aware of the proper order. Only programmer/constructor knows is. Compiler should not take more responsibility and enforce the wrong order onto programmer. Saying that I cannot initialize some fields because I did not ininialized the others is like "you cannot initialize the thing because it is not initialized". This is a kind of argument we have. So, to conclude once more, the feature that "protects" me from doing things in simple and right way in order to enforce something that does not add noticeably to the bug elimination at that is a strongly negative thing and it pisses me off, altogether with the all the arguments to support it I've seen so far. It is "a conceptual question about software development" Should there be the requirement to call super() first or not. I do not know. If you do or have an idea, you have place to answer. I think that I have provided enough arguments against this feature. Lets appreciate the ones who benefit form it. Let it just be something more than simple abstract and stupid "write your own language" or "protection" kind of argument. Why do we need it in the language that I am going to develop?

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• Using IIS Logs for Performance Testing with Visual Studio

  - by Tarun Arora

  In this blog post I’ll show you how you can play back the IIS Logs in Visual Studio to automatically generate the web performance tests. You can also download the sample solution I am demo-ing in the blog post. Introduction Performance testing is as important for new websites as it is for evolving websites. If you already have your website running in production you could mine the information available in IIS logs to analyse the dense zones (most used pages) and performance test those pages rather than wasting time testing & tuning the least used pages in your application. What are IIS Logs To help with server use and analysis, IIS is integrated with several types of log files. These log file formats provide information on a range of websites and specific statistics, including Internet Protocol (IP) addresses, user information and site visits as well as dates, times and queries. If you are using IIS 7 and above you will find the log files in the following directory C:\Interpub\Logs\ Walkthrough 1. Download and Install Log Parser from the Microsoft download Centre. You should see the LogParser.dll in the install folder, the default install location is C:\Program Files (x86)\Log Parser 2.2. LogParser.dll gives us a library to query the iis log files programmatically. By the way if you haven’t used Log Parser in the past, it is a is a powerful, versatile tool that provides universal query access to text-based data such as log files, XML files and CSV files, as well as key data sources on the Windows operating system such as the Event Log, the Registry, the file system, and Active Directory. More details… 2. Create a new test project in Visual Studio. Let’s call it IISLogsToWebPerfTestDemo.   3.  Delete the UnitTest1.cs class that gets created by default. Right click the solution and add a project of type class library, name it, IISLogsToWebPerfTestEngine. Delete the default class Program.cs that gets created with the project. 4. Under the IISLogsToWebPerfTestEngine project add a reference to Microsoft.VisualStudio.QualityTools.WebTestFramework – c:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\PublicAssemblies\Microsoft.VisualStudio.QualityTools.WebTestFramework.dll LogParser also called MSUtil - c:\users\tarora\documents\visual studio 2010\Projects\IisLogsToWebPerfTest\IisLogsToWebPerfTestEngine\obj\Debug\Interop.MSUtil.dll 5. Right click IISLogsToWebPerfTestEngine project and add a new classes – IISLogReader.cs The IISLogReader class queries the iis logs using the log parser. using System; using System.Collections.Generic; using System.Text; using MSUtil; using LogQuery = MSUtil.LogQueryClassClass; using IISLogInputFormat = MSUtil.COMIISW3CInputContextClassClass; using LogRecordSet = MSUtil.ILogRecordset; using Microsoft.VisualStudio.TestTools.WebTesting; using System.Diagnostics; namespace IisLogsToWebPerfTestEngine { // By making use of log parser it is possible to query the iis log using select queries public class IISLogReader { private string _iisLogPath; public IISLogReader(string iisLogPath) { _iisLogPath = iisLogPath; } public IEnumerable<WebTestRequest> GetRequests() { LogQuery logQuery = new LogQuery(); IISLogInputFormat iisInputFormat = new IISLogInputFormat(); // currently these columns give us suffient information to construct the web test requests string query = @"SELECT s-ip, s-port, cs-method, cs-uri-stem, cs-uri-query FROM " + _iisLogPath; LogRecordSet recordSet = logQuery.Execute(query, iisInputFormat); // Apply a bit of transformation while (!recordSet.atEnd()) { ILogRecord record = recordSet.getRecord(); if (record.getValueEx("cs-method").ToString() == "GET") { string server = record.getValueEx("s-ip").ToString(); string path = record.getValueEx("cs-uri-stem").ToString(); string querystring = record.getValueEx("cs-uri-query").ToString(); StringBuilder urlBuilder = new StringBuilder(); urlBuilder.Append("http://"); urlBuilder.Append(server); urlBuilder.Append(path); if (!String.IsNullOrEmpty(querystring)) { urlBuilder.Append("?"); urlBuilder.Append(querystring); } // You could make substitutions by introducing parameterized web tests. WebTestRequest request = new WebTestRequest(urlBuilder.ToString()); Debug.WriteLine(request.UrlWithQueryString); yield return request; } recordSet.moveNext(); } Console.WriteLine(" That's it! Closing the reader"); recordSet.close(); } } }   6. Connect the dots by adding the project reference ‘IisLogsToWebPerfTestEngine’ to ‘IisLogsToWebPerfTest’. Right click the ‘IisLogsToWebPerfTest’ project and add a new class ‘WebTest1Coded.cs’ The WebTest1Coded.cs inherits from the WebTest class. By overriding the GetRequestMethod we can inject the log files to the IISLogReader class which uses Log parser to query the log file and extract the web requests to generate the web test request which is yielded back for play back when the test is run. namespace IisLogsToWebPerfTest { using System; using System.Collections.Generic; using System.Text; using Microsoft.VisualStudio.TestTools.WebTesting; using Microsoft.VisualStudio.TestTools.WebTesting.Rules; using IisLogsToWebPerfTestEngine; // This class is a coded web performance test implementation, that simply passes // the path of the iis logs to the IisLogReader class which does the heavy // lifting of reading the contents of the log file and converting them to tests. // You could have multiple such classes that inherit from WebTest and implement // GetRequestEnumerator Method and pass differnt log files for different tests. public class WebTest1Coded : WebTest { public WebTest1Coded() { this.PreAuthenticate = true; } public override IEnumerator<WebTestRequest> GetRequestEnumerator() { // substitute the highlighted path with the path of the iis log file IISLogReader reader = new IISLogReader(@"C:\Demo\iisLog1.log"); foreach (WebTestRequest request in reader.GetRequests()) { yield return request; } } } }   7. Its time to fire the test off and see the iis log playback as a web performance test. From the Test menu choose Test View Window you should be able to see the WebTest1Coded test show up. Highlight the test and press Run selection (you can also debug the test in case you face any failures during test execution). 8. Optionally you can create a Load Test by keeping ‘WebTest1Coded’ as the base test. Conclusion You have just helped your testing team, you now have become the coolest developer in your organization! Jokes apart, log parser and web performance test together allow you to save a lot of time by not having to worry about what to test or even worrying about how to record the test. If you haven’t already, download the solution from here. You can take this to the next level by using LogParser to extract the log files as part of an end of day batch to a database. See the usage trends by user this solution over a longer term and have your tests consume the web requests now stored in the database to generate the web performance tests. If you like the post, don’t forget to share … Keep RocKiNg!

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• How to implement smooth flocking

  - by Craig

  I'm working on a simple survival game, avoid the big guy and chase the the small guys to stay alive for as long as possible. I have taken the chase and evade example from MSDN create and drawn 20 mice on the screen. I want the small guys to flock when they arent evading. They are doing this, but it isnt as smooth as I would like it to be. How do i make the movement smoother? Its very jittery.# Below is what I have going at the moment, flocking code is within the IF statement, when it isnt set to evading. Any help would be greatly appreciated! :) namespace ChaseAndEvade { class MouseSprite { public enum MouseAiState { // evading the cat Evading, // the mouse can't see the "cat", and it's wandering around. Wander } // how fast can the mouse move? public float MaxMouseSpeed = 4.5f; // and how fast can it turn? public float MouseTurnSpeed = 0.20f; // MouseEvadeDistance controls the distance at which the mouse will flee from // cat. If the mouse is further than "MouseEvadeDistance" pixels away, he will // consider himself safe. public float MouseEvadeDistance = 100.0f; // this constant is similar to TankHysteresis. The value is larger than the // tank's hysteresis value because the mouse is faster than the tank: with a // higher velocity, small fluctuations are much more visible. public float MouseHysteresis = 60.0f; public Texture2D mouseTexture; public Vector2 mouseTextureCenter; public Vector2 mousePosition; public MouseAiState mouseState = MouseAiState.Wander; public float mouseOrientation; public Vector2 mouseWanderDirection; int separationImpact = 4; int cohesionImpact = 6; int alignmentImpact = 2; int sensorDistance = 50; public void UpdateMouse(Vector2 position, MouseSprite [] mice, int numberMice, int index) { Vector2 catPosition = position; int enemies = numberMice; // first, calculate how far away the mouse is from the cat, and use that // information to decide how to behave. If they are too close, the mouse // will switch to "active" mode - fleeing. if they are far apart, the mouse // will switch to "idle" mode, where it roams around the screen. // we use a hysteresis constant in the decision making process, as described // in the accompanying doc file. float distanceFromCat = Vector2.Distance(mousePosition, catPosition); // the cat is a safe distance away, so the mouse should idle: if (distanceFromCat > MouseEvadeDistance + MouseHysteresis) { mouseState = MouseAiState.Wander; } // the cat is too close; the mouse should run: else if (distanceFromCat < MouseEvadeDistance - MouseHysteresis) { mouseState = MouseAiState.Evading; } // if neither of those if blocks hit, we are in the "hysteresis" range, // and the mouse will continue doing whatever it is doing now. // the mouse will move at a different speed depending on what state it // is in. when idle it won't move at full speed, but when actively evading // it will move as fast as it can. this variable is used to track which // speed the mouse should be moving. float currentMouseSpeed; // the second step of the Update is to change the mouse's orientation based // on its current state. if (mouseState == MouseAiState.Evading) { // If the mouse is "active," it is trying to evade the cat. The evasion // behavior is accomplished by using the TurnToFace function to turn // towards a point on a straight line facing away from the cat. In other // words, if the cat is point A, and the mouse is point B, the "seek // point" is C. // C // B // A Vector2 seekPosition = 2 * mousePosition - catPosition; // Use the TurnToFace function, which we introduced in the AI Series 1: // Aiming sample, to turn the mouse towards the seekPosition. Now when // the mouse moves forward, it'll be trying to move in a straight line // away from the cat. mouseOrientation = ChaseAndEvadeGame.TurnToFace(mousePosition, seekPosition, mouseOrientation, MouseTurnSpeed); // set currentMouseSpeed to MaxMouseSpeed - the mouse should run as fast // as it can. currentMouseSpeed = MaxMouseSpeed; } else { // if the mouse isn't trying to evade the cat, it should just meander // around the screen. we'll use the Wander function, which the mouse and // tank share, to accomplish this. mouseWanderDirection and // mouseOrientation are passed by ref so that the wander function can // modify them. for more information on ref parameters, see // http://msdn2.microsoft.com/en-us/library/14akc2c7(VS.80).aspx ChaseAndEvadeGame.Wander(mousePosition, ref mouseWanderDirection, ref mouseOrientation, MouseTurnSpeed); // if the mouse is wandering, it should only move at 25% of its maximum // speed. currentMouseSpeed = .25f * MaxMouseSpeed; Vector2 separate = Vector2.Zero; Vector2 moveCloser = Vector2.Zero; Vector2 moveAligned = Vector2.Zero; // What the AI does when it sees other AIs for (int j = 0; j < enemies; j++) { if (index != j) { // Calculate a vector towards another AI Vector2 separation = mice[index].mousePosition - mice[j].mousePosition; // Only react if other AI is within a certain distance if ((separation.Length() < this.sensorDistance) & (separation.Length()> 0) ) { moveAligned += mice[j].mouseWanderDirection; float distance = Math.Abs(separation.Length()); if (distance == 0) distance = 1; moveCloser += mice[j].mousePosition; separation.Normalize(); separate += separation / distance; } } } if (moveAligned.LengthSquared() != 0) { moveAligned.Normalize(); } if (moveCloser.LengthSquared() != 0) { moveCloser.Normalize(); } moveCloser /= enemies; mice[index].mousePosition += (separate * separationImpact) + (moveCloser * cohesionImpact) + (moveAligned * alignmentImpact); } // The final step is to move the mouse forward based on its current // orientation. First, we construct a "heading" vector from the orientation // angle. To do this, we'll use Cosine and Sine to tell us the x and y // components of the heading vector. See the accompanying doc for more // information. Vector2 heading = new Vector2( (float)Math.Cos(mouseOrientation), (float)Math.Sin(mouseOrientation)); // by multiplying the heading and speed, we can get a velocity vector. the // velocity vector is then added to the mouse's current position, moving him // forward. mousePosition += heading * currentMouseSpeed; } } }

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• Subscript out of range error in VBScript script

  - by user3912

  I'm trying to move my entire User folder in Windows Vista to a non-system partition. To do so with a minimum hassle I'm following the directions provided at Ben's Blog, specifically the VBScript he provides. However executing the script throws up an error which I can't resolve myself. Here's the VBScript code followed by the text file it works from, and finally my error message. How do I correct the problem? VBScript Code: '# Perform dir /a c:\users > c:\dir.txt '# place this script file in c:\ too '# double click to run it '# run resulting script.bat from recovery mode repprefix = " Directory of..." ' Modify to your language sourcedrive = "C:\" targetdrive = "D:\" altsourcedrive = "C:\" 'leave same as target drive unless otherwise indicated alttargetdrive = "E:\" 'leave same as target drive unless otherwise indicated inname = "dir.txt" outname = "script.bat" userroot = "Users" set fso = CreateObject("Scripting.FileSystemObject") ' construct batch commands for saving rights, then link, the recreating rights Function GetCommand(curroot, line, typ, keyword) ' first need to get source and target pos = Instr(line, keyword) + Len(keyword) tuple = Trim(Mid(line, pos)) arr = Split(tuple, "[") oldtarget = Replace(arr(1), "]", "") oldlink = curroot & "\" & Trim(arr(0)) ' need to determine if we are pointing back to old disk newlink = replace(oldlink, sourcedrive, targetdrive) if(Instr(oldtarget, sourcedrive & userroot)) then newtarget = Replace(oldtarget, sourcedrive, targetdrive) else newtarget = oldtarget ' still pointing to original target end if ' comment out = "echo " & newlink & " --- " & newtarget & vbCrLf ' save permissions out = out & "icacls """ & replace(oldlink, sourcedrive, altsourcedrive) & """ /L /save " & altsourcedrive & "permissions.txt" & vbCrLf ' create link newlink = replace(newlink, targetdrive, alttargetdrive) if typ = "junction" then out = out & "mklink /j """ & newlink & """ """ & newtarget & """" & vbCrLf else ' typ = "symlink" out = out & "mklink /d """ & newlink & """ """ & newtarget & """" & vbCrLf end if 'set hidden attribute out = out & "attrib +h """ & newlink & """ /L" & vbCrLf ' apply permissions shortlink = Left(newlink, InstrRev(newlink, "\") - 1) 'icacls works strangely - non-orthogonal for restore out = out & "icacls """ & shortlink & """ /L /restore " & altsourcedrive & "permissions.txt" & vbCrLf GetCommand = out & vbCrLf End Function Sub WriteToFile(file, text) ForWriting = 2 Create = true set outfile = fso.OpenTextFile(file, ForWriting, Create) Call outfile.Write(text) Call outfile.Close() End Sub outtext = "ROBOCOPY " & altsourcedrive & userroot & " " & alttargetdrive & userroot & " /E /COPYALL /XJ" & vbCrLf & vbCrLf set intext = fso.OpenTextFile(inname) while not intext.AtEndOfStream line = intext.ReadLine() if Instr(line, repprefix) then curroot = Replace(line, repprefix, "") elseif Instr(line, juncname) then outtext = outtext & GetCommand(curroot, line, "junction", juncname) elseif Instr(line, linkname) then outtext = outtext & GetCommand(curroot, line, "symlink", linkname) end if Wend outtext = outtext & "icacls " & altsourcedrive & userroot & " /L /save " & altsourcedrive & "permissions.txt" & vbCrLf outtext = outtext & "ren " & altsourcedrive & userroot & " _" & userroot & vbCrLf outtext = outtext & "mklink /j " & altsourcedrive & userroot & " " & targetdrive & userroot & vbCrLf outtext = outtext & "icacls " & altsourcedrive & " /L /restore " & altsourcedrive & "permissions.txt" Call intext.Close() Call WriteToFile(outname, outtext) MsgBox("Done writing to " & outname) dir.txt: Volume in drive C is ACER Volume Serial Number is 08D7-C0CC Directory of c:\users 07/16/2009 12:29 PM {DIR} . 07/16/2009 12:29 PM {DIR} .. 11/02/2006 09:02 AM {SYMLINKD} All Users [C:\ProgramData] 11/02/2006 09:02 AM {DIR} Default 11/02/2006 09:02 AM {JUNCTION} Default User [C:\Users\Default] 08/21/2008 08:37 AM 174 desktop.ini 11/02/2006 08:50 AM {DIR} Public 07/19/2009 08:54 PM {DIR} Steve 1 File(s) 174 bytes 7 Dir(s) 5,679,947,776 bytes free Error Message: Windows Script Host Script: C:\user location.vbs Line: 25 Char: 2 Error: Subscript out of range: '[number: 1]' Code: 800A0009 Source: Microsoft VBScript runtime error (In the VBScript script that I'm using on my system, I believe that 'Line 25' corresponds to the line beginning with oldtarget = Replace(arr(1), "]", "").

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• Subscript out of range error in VBScript script

  - by SteveW

  I'm trying to move my entire User folder in Windows Vista to a non-system partition. To do so with a minimum hassle I'm following the directions provided at Ben's Blog, specifically the VBScript he provides. However executing the script throws up an error which I can't resolve myself. Here's the VBScript code followed by the text file it works from, and finally my error message. How do I correct the problem? VBScript Code: '# Perform dir /a c:\users > c:\dir.txt '# place this script file in c:\ too '# double click to run it '# run resulting script.bat from recovery mode repprefix = " Directory of..." ' Modify to your language sourcedrive = "C:\" targetdrive = "D:\" altsourcedrive = "C:\" 'leave same as target drive unless otherwise indicated alttargetdrive = "E:\" 'leave same as target drive unless otherwise indicated inname = "dir.txt" outname = "script.bat" userroot = "Users" set fso = CreateObject("Scripting.FileSystemObject") ' construct batch commands for saving rights, then link, the recreating rights Function GetCommand(curroot, line, typ, keyword) ' first need to get source and target pos = Instr(line, keyword) + Len(keyword) tuple = Trim(Mid(line, pos)) arr = Split(tuple, "[") oldtarget = Replace(arr(1), "]", "") oldlink = curroot & "\" & Trim(arr(0)) ' need to determine if we are pointing back to old disk newlink = replace(oldlink, sourcedrive, targetdrive) if(Instr(oldtarget, sourcedrive & userroot)) then newtarget = Replace(oldtarget, sourcedrive, targetdrive) else newtarget = oldtarget ' still pointing to original target end if ' comment out = "echo " & newlink & " --- " & newtarget & vbCrLf ' save permissions out = out & "icacls """ & replace(oldlink, sourcedrive, altsourcedrive) & """ /L /save " & altsourcedrive & "permissions.txt" & vbCrLf ' create link newlink = replace(newlink, targetdrive, alttargetdrive) if typ = "junction" then out = out & "mklink /j """ & newlink & """ """ & newtarget & """" & vbCrLf else ' typ = "symlink" out = out & "mklink /d """ & newlink & """ """ & newtarget & """" & vbCrLf end if 'set hidden attribute out = out & "attrib +h """ & newlink & """ /L" & vbCrLf ' apply permissions shortlink = Left(newlink, InstrRev(newlink, "\") - 1) 'icacls works strangely - non-orthogonal for restore out = out & "icacls """ & shortlink & """ /L /restore " & altsourcedrive & "permissions.txt" & vbCrLf GetCommand = out & vbCrLf End Function Sub WriteToFile(file, text) ForWriting = 2 Create = true set outfile = fso.OpenTextFile(file, ForWriting, Create) Call outfile.Write(text) Call outfile.Close() End Sub outtext = "ROBOCOPY " & altsourcedrive & userroot & " " & alttargetdrive & userroot & " /E /COPYALL /XJ" & vbCrLf & vbCrLf set intext = fso.OpenTextFile(inname) while not intext.AtEndOfStream line = intext.ReadLine() if Instr(line, repprefix) then curroot = Replace(line, repprefix, "") elseif Instr(line, juncname) then outtext = outtext & GetCommand(curroot, line, "junction", juncname) elseif Instr(line, linkname) then outtext = outtext & GetCommand(curroot, line, "symlink", linkname) end if Wend outtext = outtext & "icacls " & altsourcedrive & userroot & " /L /save " & altsourcedrive & "permissions.txt" & vbCrLf outtext = outtext & "ren " & altsourcedrive & userroot & " _" & userroot & vbCrLf outtext = outtext & "mklink /j " & altsourcedrive & userroot & " " & targetdrive & userroot & vbCrLf outtext = outtext & "icacls " & altsourcedrive & " /L /restore " & altsourcedrive & "permissions.txt" Call intext.Close() Call WriteToFile(outname, outtext) MsgBox("Done writing to " & outname) dir.txt: Volume in drive C is ACER Volume Serial Number is 08D7-C0CC Directory of c:\users 07/16/2009 12:29 PM {DIR} . 07/16/2009 12:29 PM {DIR} .. 11/02/2006 09:02 AM {SYMLINKD} All Users [C:\ProgramData] 11/02/2006 09:02 AM {DIR} Default 11/02/2006 09:02 AM {JUNCTION} Default User [C:\Users\Default] 08/21/2008 08:37 AM 174 desktop.ini 11/02/2006 08:50 AM {DIR} Public 07/19/2009 08:54 PM {DIR} Steve 1 File(s) 174 bytes 7 Dir(s) 5,679,947,776 bytes free Error Message: Windows Script Host Script: C:\user location.vbs Line: 25 Char: 2 Error: Subscript out of range: '[number: 1]' Code: 800A0009 Source: Microsoft VBScript runtime error (In the VBScript script that I'm using on my system, I believe that 'Line 25' corresponds to the line beginning with oldtarget = Replace(arr(1), "]", "").

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• Updating with using custom class collection not working

  - by Risho

  I've posted this yesterday on asp forum but no one replied so perhaps I'll have better luck here. For some reason the OnUpdating method does not pull new values from the grid which is in edit mode. I've search and have come across several blogs and sites, some sugesting that an ObjectDataSource is required in order to use the "e.NewValue" construct others provide code to the contrary. I don't get any errors - the variables in the code file would contain the old values rather then new ones. I don't want to use the ODS way of manipulating the data. My delete method works but not the update one. Can you suggest what is wrong with the code? Here is what I've got: aspx file: <asp:GridView ID="gvBlack" runat="server" AutoGenerateColumns="False" OnRowUpdating="gvBlack_OnUpdating" OnRowEditing="gvBlack_RowEditing"> <Columns> <%--<asp:BoundField DataField="Ident_Black" ReadOnly="True" visible="false" />--%> <asp:TemplateField ItemStyle-Width="1px"> <EditItemTemplate> <asp:Label ID="lblIdent_Black" runat="server" Text='<%# Bind("Ident_Black") %>' Visible="false" /> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Model" > <ItemTemplate> <asp:Label ID="lblModel_Black" runat="server" Text='<%# Bind("Model_Black") %>' width="130px" /> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="txtModel_Black" runat="server" Text='<%# Eval("Model_Black") %>' width="100px" /> <asp:RequiredFieldValidator ID="rfvModel_Black" runat="server" ControlToValidate="txtModel_Black" SetFocusOnError="true" ErrorMessage="*" ValidationGroup="CurrentMfg" ForeColor="Red" Font-Bold="true" /> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Description" > <ItemTemplate> <asp:Label ID="lblDesc_Black" runat="server" Text='<%# Bind("Desc_Black") %>' width="200px" /> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="txtDesc_Black" runat="server" Text='<%# Eval("Desc_Black") %>' width="170px" /> <span></span> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Qty" > <ItemTemplate> <asp:Label ID="lblQty_Black" runat="server" Text='<%# Bind("Qty_Black") %>' width="35px" /> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="txtQty_Black" runat="server" Text='<%# Eval("Qty_Black") %>' width="35px" /> <asp:RequiredFieldValidator ID="rfvQty_Black" runat="server" ControlToValidate="txtQty_Black" SetFocusOnError="true" ErrorMessage="*" ValidationGroup="CurrentMfg" ForeColor="Red" Font-Bold="true" /> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Reorder<br />Limit"> <ItemTemplate> <asp:Label ID="lblBlack_Reorder_Limit" runat="server" Text='<%# Bind("Black_Reorder_Limit") %>' width="35px" /> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="txtBlack_Reorder_Limit" runat="server" Text='<%# Eval("Black_Reorder_Limit") %>' width="35px" /> <asp:RequiredFieldValidator ID="rfvBlack_Reorder_Limit" runat="server" ControlToValidate="txtBlack_Reorder_Limit" SetFocusOnError="true" ErrorMessage="*" ValidationGroup="CurrentMfg" ForeColor="Red" Font-Bold="true" /> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Notes"> <ItemTemplate> <asp:Label ID="lblNotes" runat="server" Text='<%# Bind("Notes") %>' width="200px" /> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="txtNotes" runat="server" Text='<%# Eval("Notes") %>' width="170px" /> <span></span> </EditItemTemplate> </asp:TemplateField> <asp:CommandField ShowEditButton="True" ShowDeleteButton="false" ValidationGroup="CurrentToner" /> </Columns> </asp:GridView> aspx.cs file: protected void Page_Load(object sender, EventArgs e) { LoadData_TonerBlack(); } private void LoadData_TonerBlack() { dalConsumables_TonerBlack drTonerBlack = new dalConsumables_TonerBlack(); gvBlack.DataSource = drTonerBlack.GetListTonersBlack(); gvBlack.DataBind(); } protected void gvBlack_OnUpdating(object sender, GridViewUpdateEventArgs e) { //GridView gvBlack = (GridView)sender; //GridViewRow gvBlackRow = (GridViewRow)gvBlack.Rows[e.RowIndex]; int _Ident_Black = Convert.ToInt32(gvBlack.DataKeys[e.RowIndex].Values[0].ToString()); TextBox _txtModel_Black = (TextBox)gvBlack.Rows[e.RowIndex].FindControl("txtModel_Black"); TextBox _txtDesc_Black = (TextBox)gvBlack.Rows[e.RowIndex].FindControl("txtDesc_Black"); TextBox _txtQty_Black = (TextBox)gvBlack.Rows[e.RowIndex].FindControl("txtQty_Black"); TextBox _txtBlack_Reorder_Limit = (TextBox)gvBlack.Rows[e.RowIndex].FindControl("txtBlack_Reorder_Limit"); TextBox _txtNotes = (TextBox)gvBlack.Rows[e.RowIndex].FindControl("txtNotes"); string _updatedBy = Request.ServerVariables["AUTH_USER"].ToString(); dalConsumables_TonerBlack updateTonerBlack = new dalConsumables_TonerBlack(); updateTonerBlack.UpdateTonerBlack(_Ident_Black, _txtModel_Black.Text, _txtDesc_Black.Text, Convert.ToInt32(_txtQty_Black.Text), Convert.ToInt32(_txtBlack_Reorder_Limit.Text), _txtNotes.Text, _updatedBy); gvBlack.EditIndex = -1; LoadData_TonerBlack(); } protected void gvBlack_RowEditing(object sender, GridViewEditEventArgs e) { gvBlack.EditIndex = e.NewEditIndex; LoadData_TonerBlack(); } Thanks in advance! Risho

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• December release of Microsoft All-In-One Code Framework is available now.

  - by Jialiang

  The code samples in Microsoft All-In-One Code Framework are updated on 2010-12-13. Download address: http://1code.codeplex.com/releases/view/57459#DownloadId=185534 Updated code sample index categorized by technologies: http://1code.codeplex.com/wikipage?title=All-In-One%20Code%20Framework%20Sample%20Catalog (it also allows you to download individual code samples instead of the entire All-In-One Code Framework sample package.) If it’s the first time that you hear about Microsoft All-In-One Code Framework, please watch the introduction video on YouTube http://www.youtube.com/watch?v=cO5Li3APU58, or read the introduction on our homepage http://1code.codeplex.com/,  and this Port25 article http://port25.technet.com/archive/2010/01/18/the-all-in-one-code-framework.aspx.  -------------- New ASP.NET Code Samples VBASPNETAJAXWebChat and CSASPNETAJAXWebChat Most of you have some experience in chatting with friends on the web. So you may want to know how to make a web chat application, it seems to be quite complicated. But ASP.NET gives you the power to buiild a chat room easily. In this code sample, we will construct our own web chat room with the amazing AJAX feature. The principle is simple relatively. As we all know, a base chat application need 4 base controls: one List control to show the chat room members, one List control to show the message list, one TextBox control to input messages and one button to send message. User inputs his message in the textbox first and then presses Send button, it will send the message to the server. The message list will update every 2 seconds to get the newest message list in the chat room from the server. We need to know, it is hard for us to make an AJAX web chat application like a windows form application because we cannot keep the connection after one web request ended. So a lot of events which communicates between client side and server side cannot be realized. The common workaround is to make web requests in every some seconds to check whether the server side has been updated. But another technique called COMET makes it possible. But it is different with AJAX and will not be talked in details in this KB. For more details about COMET, we can get some clues from the Reference.   CSASPNETCurrentOnlineUserList and VBASPNETCurrentOnlineUserList This sample demos a system that needs to display a list of current online users' information. As a matter of fact, Membership.GetNumberOfUsersOnline Method  can get the number of online users and there is a convenient approach to check whether the user is online by using Membership.GetUser(string userName).IsOnline property,however many asp.net projects are not using membership.So in this case,the sample shows how to display a list of current online users' information without using membership provider. It is not difficult to check whether the user is online by using session.Many projects tend to be used “Session_End” event to mark a user as “Offline”,however ,it may not be a good idea,because it can’t detect the user status accurately. In addition, "Session_End" event is only available in the "InProc" session mode. If you are storing session states in the State Server or SQL Server, "Session_End" event will never fire. To handle this issue, we need to save the user online status to a  global DataTable or  DataBase. In the sample application, define a global DataTable to store the information of online users.Use XmlHttpRequest in the pages to update and check user's last active time at intervals and also retrieve information on how many users are still online. The sample project can auto delete offline users' information from a global DataTable by checking users’ last active time. A step-by-step guide illustrating how to display a list of current online users' information without using membership provider: 1. Login page. Let user sign in and add current user’s information to a global datatable while Initialize the global datatable which used to store information of current online users. 2. Current online user list page. Use XmlHttpRequest in this page to update and check user's last active time at intervals and also retrieve information on how many users are still online. 3. If user closes the page without clicking  the sign out link button ,the sample project can auto mark the user as offline and delete offline users' information from a global DataTable which used to store information of current online users  by checking users’ last active time. Then the current online user list will be like this:   CSASPNETIPtoLocation This sample demonstrates how to find the geographical location from an IP address. As we know, it is not hard for us to get the IP address of visitors via Request.ServerVariable property, but it is really difficult for us to know where they come from. To achieve this feature, the sample uses a free third party web service from http://freegeoip.appspot.com/, which returns the information about an IP address we send to the server in the format of XML, JSON or CSV. It makes all things easier.   CSASPNETBackgroundWorker Sometimes we do an operation which needs long time to complete. It will stop the response and the page is blank until the operation finished. In this case, we want the operation to run in the background, and in the page, we want to display the progress of the running operation. Therefore, the user can know the operation is running and can know the progress. CSASPNETInheritingFromTreeNode In windows forms TreeView, each tree node has a property called "Tag" which can be used to store a custom object. Many customers want to implement the same tag feature in ASP.NET TreeView. This project creates a custom TreeView control named "CustomTreeView" to achieve this goal. CSASPNETRemoteUploadAndDownload and VBASPNETRemoteUploadAndDownload This code sample was created in response to a code sample request in our new code sample request frunction for customers. The code samples demonstrate uploading files to and downloading files from a remote HTTP or FTP server. In .NET Framework 2.0 and higher versions, there are some lightweight class libraries which support HTTP and FTP protocol transmission. By using these classes, we can achieve this programming requirement.   CSASPNETImageEditUpload and VBASPNETImageEditUpload This demo will shows how to insert, edit and update a common image with the type of "jpg", "png", "gif" or "bmp" . We mainly use two different SqlDataSources with the same database to bind to GridView and FormView in order to establish the “cascading” effort. Besides we apply our self-made ImageHanlder to encoding or decoding images of different types, and use context to output the stream of images. We will explicitly assign the binary streams of images through the event of “FormView_ItemInserting” or “Form_ItemUpdating” to synchronize the stream both in what we can see on an aspx page as well as in what’s really stored in the database.   WebBrowser Control, Network and other Windows General New Code Samples   CSWebBrowserSuppressError and VBWebBrowserSuppressError The sample demonstrates how to make WebBrowser suppress errors, such as script error, navigation error and so on.   CSWebBrowserWithProxy and VBWebBrowserWithProxy The sample demonstrates how to make WebBrowser use a proxy server.   CSWebDownloadProgress and VBWebDownloadProgress The sample demonstrates how to show progress during the download. It also supplies the features to Start, Pause, Resume and Cancel a download.   CppSetDesktopWallpaper, CSSetDesktopWallpaper and VBSetDesktopWallpaper This code sample application allows you select an image, view a preview (resized smaller to fit if necessary), select a display style among Tile, Center, Stretch, Fit (Windows 7 and later) and Fill (Windows 7 and later), and set the image as the Desktop wallpaper. CSWindowsServiceRecoveryProperty and VBWindowsServiceRecoveryProperty CSWindowsServiceRecoveryProperty example demonstrates how to use ChangeServiceConfig2 to configure the service "Recovery" properties in C#. This example operates all the options you can see on the service "Recovery" tab, including setting the "Enable actions for stops with errors" option in Windows Vista and later operating systems. This example also include how to grant the shut down privilege to the process, so that we can configure a special option in the "Recovery" tab - "Restart Computer Options...".   New Office Development Code Samples   CSOneNoteRibbonAddIn and VBOneNoteRibbonAddIn The code sample demonstrates a OneNote 2010 COM add-in that implements IDTExtensibility2. The add-in also supports customizing the Ribbon by implementing the IRibbonExtensibility interface. It is a skeleton OneNote add-in that developers can extend it to implement more functions. The code sample was requested by a customer in our code sample request service. We expect that this could help developers in the community.   New Windows Shell Code Samples   CppShellExtPreviewHandler, CSShellExtPreviewHandler and VBShellExtPreviewHandler In the past two months, we released the code samples of Windows Context Menu Handler, Infotip Handler, and Thumbnail Handler. This is the fourth part of the shell extension series: Preview Handler. The code samples demo the C++, C# and VB.NET implementation of a preview handler for a new file type registered with the .recipe extension. Preview handlers are called when an item is selected to show a lightweight, rich, read-only preview of the file's contents in the view's reading pane. This is done without launching the file's associated application. Windows Vista and later operating systems support preview handlers. To be a valid preview handler, several interfaces must be implemented. This includes IPreviewHandler (shobjidl.h); IInitializeWithFile, IInitializeWithStream, or IInitializeWithItem (propsys.h); IObjectWithSite (ocidl.h); and IOleWindow (oleidl.h). There are also optional interfaces, such as IPreviewHandlerVisuals (shobjidl.h), that a preview handler can implement to provide extended support. Windows API Code Pack for Microsoft .NET Framework makes the implementation of these interfaces very easy in .NET. The example preview handler provides previews for .recipe files. The .recipe file type is simply an XML file registered as a unique file name extension. It includes the title of the recipe, its author, difficulty, preparation time, cook time, nutrition information, comments, an embedded preview image, and so on. The preview handler extracts the title, comments, and the embedded image, and display them in a preview window.   In response to many customers' request, we added setup projects in every shell extension samples in this release. Those setup projects allow you to deploy the shell extensions to your end users' machines. ---------- Download address: http://1code.codeplex.com/releases/view/57459#DownloadId=185534 Updated code sample index categorized by technologies: http://1code.codeplex.com/wikipage?title=All-In-One%20Code%20Framework%20Sample%20Catalog (it also allows you to download individual code samples instead of the entire All-In-One Code Framework sample package.) If you have any feedback for us, please email: [email protected]. We look forward to your comments.

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• C# Neural Networks with Encog

  - by JoshReuben

  Neural Networks ·       I recently read a book Introduction to Neural Networks for C# , by Jeff Heaton. http://www.amazon.com/Introduction-Neural-Networks-C-2nd/dp/1604390093/ref=sr_1_2?ie=UTF8&s=books&qid=1296821004&sr=8-2-spell. Not the 1st ANN book I've perused, but a nice revision.   ·       Artificial Neural Networks (ANNs) are a mechanism of machine learning – see http://en.wikipedia.org/wiki/Artificial_neural_network , http://en.wikipedia.org/wiki/Category:Machine_learning ·       Problems Not Suited to a Neural Network Solution- Programs that are easily written out as flowcharts consisting of well-defined steps, program logic that is unlikely to change, problems in which you must know exactly how the solution was derived. ·       Problems Suited to a Neural Network – pattern recognition, classification, series prediction, and data mining. Pattern recognition - network attempts to determine if the input data matches a pattern that it has been trained to recognize. Classification - take input samples and classify them into fuzzy groups. ·       As far as machine learning approaches go, I thing SVMs are superior (see http://en.wikipedia.org/wiki/Support_vector_machine ) - a neural network has certain disadvantages in comparison: an ANN can be overtrained, different training sets can produce non-deterministic weights and it is not possible to discern the underlying decision function of an ANN from its weight matrix – they are black box. ·       In this post, I'm not going to go into internals (believe me I know them). An autoassociative network (e.g. a Hopfield network) will echo back a pattern if it is recognized. ·       Under the hood, there is very little maths. In a nutshell - Some simple matrix operations occur during training: the input array is processed (normalized into bipolar values of 1, -1) - transposed from input column vector into a row vector, these are subject to matrix multiplication and then subtraction of the identity matrix to get a contribution matrix. The dot product is taken against the weight matrix to yield a boolean match result. For backpropogation training, a derivative function is required. In learning, hill climbing mechanisms such as Genetic Algorithms and Simulated Annealing are used to escape local minima. For unsupervised training, such as found in Self Organizing Maps used for OCR, Hebbs rule is applied. ·       The purpose of this post is not to mire you in technical and conceptual details, but to show you how to leverage neural networks via an abstraction API - Encog   Encog ·       Encog is a neural network API ·       Links to Encog: http://www.encog.org , http://www.heatonresearch.com/encog, http://www.heatonresearch.com/forum ·       Encog requires .Net 3.5 or higher – there is also a Silverlight version. Third-Party Libraries – log4net and nunit. ·       Encog supports feedforward, recurrent, self-organizing maps, radial basis function and Hopfield neural networks. ·       Encog neural networks, and related data, can be stored in .EG XML files. ·       Encog Workbench allows you to edit, train and visualize neural networks. The Encog Workbench can generate code. Synapses and layers ·       the primary building blocks - Almost every neural network will have, at a minimum, an input and output layer. In some cases, the same layer will function as both input and output layer. ·       To adapt a problem to a neural network, you must determine how to feed the problem into the input layer of a neural network, and receive the solution through the output layer of a neural network. ·       The Input Layer - For each input neuron, one double value is stored. An array is passed as input to a layer. Encog uses the interface INeuralData to hold these arrays. The class BasicNeuralData implements the INeuralData interface. Once the neural network processes the input, an INeuralData based class will be returned from the neural network's output layer. ·       convert a double array into an INeuralData object : INeuralData data = new BasicNeuralData(= new double[10]); ·       the Output Layer- The neural network outputs an array of doubles, wraped in a class based on the INeuralData interface. ·        The real power of a neural network comes from its pattern recognition capabilities. The neural network should be able to produce the desired output even if the input has been slightly distorted. ·       Hidden Layers– optional. between the input and output layers. very much a “black box”. If the structure of the hidden layer is too simple it may not learn the problem. If the structure is too complex, it will learn the problem but will be very slow to train and execute. Some neural networks have no hidden layers. The input layer may be directly connected to the output layer. Further, some neural networks have only a single layer. A single layer neural network has the single layer self-connected. ·       connections, called synapses, contain individual weight matrixes. These values are changed as the neural network learns. Constructing a Neural Network ·       the XOR operator is a frequent “first example” -the “Hello World” application for neural networks. ·       The XOR Operator- only returns true when both inputs differ. 0 XOR 0 = 0 1 XOR 0 = 1 0 XOR 1 = 1 1 XOR 1 = 0 ·       Structuring a Neural Network for XOR  - two inputs to the XOR operator and one output. ·       input: 0.0,0.0 1.0,0.0 0.0,1.0 1.0,1.0 ·       Expected output: 0.0 1.0 1.0 0.0 ·       A Perceptron - a simple feedforward neural network to learn the XOR operator. ·       Because the XOR operator has two inputs and one output, the neural network will follow suit. Additionally, the neural network will have a single hidden layer, with two neurons to help process the data. The choice for 2 neurons in the hidden layer is arbitrary, and often comes down to trial and error. ·       Neuron Diagram for the XOR Network ·       ·       The Encog workbench displays neural networks on a layer-by-layer basis. ·       Encog Layer Diagram for the XOR Network:   ·       Create a BasicNetwork - Three layers are added to this network. the FinalizeStructure method must be called to inform the network that no more layers are to be added. The call to Reset randomizes the weights in the connections between these layers. var network = new BasicNetwork(); network.AddLayer(new BasicLayer(2)); network.AddLayer(new BasicLayer(2)); network.AddLayer(new BasicLayer(1)); network.Structure.FinalizeStructure(); network.Reset(); ·       Neural networks frequently start with a random weight matrix. This provides a starting point for the training methods. These random values will be tested and refined into an acceptable solution. However, sometimes the initial random values are too far off. Sometimes it may be necessary to reset the weights again, if training is ineffective. These weights make up the long-term memory of the neural network. Additionally, some layers have threshold values that also contribute to the long-term memory of the neural network. Some neural networks also contain context layers, which give the neural network a short-term memory as well. The neural network learns by modifying these weight and threshold values. ·       Now that the neural network has been created, it must be trained. Training a Neural Network ·       construct a INeuralDataSet object - contains the input array and the expected output array (of corresponding range). Even though there is only one output value, we must still use a two-dimensional array to represent the output. public static double[][] XOR_INPUT ={ new double[2] { 0.0, 0.0 }, new double[2] { 1.0, 0.0 }, new double[2] { 0.0, 1.0 }, new double[2] { 1.0, 1.0 } };   public static double[][] XOR_IDEAL = { new double[1] { 0.0 }, new double[1] { 1.0 }, new double[1] { 1.0 }, new double[1] { 0.0 } };   INeuralDataSet trainingSet = new BasicNeuralDataSet(XOR_INPUT, XOR_IDEAL); ·       Training is the process where the neural network's weights are adjusted to better produce the expected output. Training will continue for many iterations, until the error rate of the network is below an acceptable level. Encog supports many different types of training. Resilient Propagation (RPROP) - general-purpose training algorithm. All training classes implement the ITrain interface. The RPROP algorithm is implemented by the ResilientPropagation class. Training the neural network involves calling the Iteration method on the ITrain class until the error is below a specific value. The code loops through as many iterations, or epochs, as it takes to get the error rate for the neural network to be below 1%. Once the neural network has been trained, it is ready for use. ITrain train = new ResilientPropagation(network, trainingSet);   for (int epoch=0; epoch < 10000; epoch++) { train.Iteration(); Debug.Print("Epoch #" + epoch + " Error:" + train.Error); if (train.Error > 0.01) break; } Executing a Neural Network ·       Call the Compute method on the BasicNetwork class. Console.WriteLine("Neural Network Results:"); foreach (INeuralDataPair pair in trainingSet) { INeuralData output = network.Compute(pair.Input); Console.WriteLine(pair.Input[0] + "," + pair.Input[1] + ", actual=" + output[0] + ",ideal=" + pair.Ideal[0]); } ·       The Compute method accepts an INeuralData class and also returns a INeuralData object. Neural Network Results: 0.0,0.0, actual=0.002782538818034049,ideal=0.0 1.0,0.0, actual=0.9903741937121177,ideal=1.0 0.0,1.0, actual=0.9836807956566187,ideal=1.0 1.0,1.0, actual=0.0011646072586172778,ideal=0.0 ·       the network has not been trained to give the exact results. This is normal. Because the network was trained to 1% error, each of the results will also be within generally 1% of the expected value.

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• New Skool Crosstabbing

  - by Tim Dexter

  A while back I spoke about having to go back to BIP's original crosstabbing solution to achieve a certain layout. Hok Min has provided a 'man' page for the new crosstab/pivot builder for 10.1.3.4.1 users. This will make the documentation drop but for now, get it here! The old, hand method is still available but this new approach, is more efficient and flexible. That said you may need to get into the crosstab code to tweak it where the crosstab dialog can not help. I had to do this, this week but more on that later. The following explains how the crosstab wizard builds the crosstab and what the fields inside the resulting template structure are there for. To create the crosstab a new XDO command "<?crosstab:...?>" has been created. XDO Command: <?crosstab: ctvarname; data-element; rows; columns; measures; aggregation?> Parameter Description Example Ctvarname Crosstab variable name. This is automatically generated by the Add-in. C123 data-element This is the XML data element that contains the data. "//ROW" Rows This contains a list of XML elements for row headers. The ordering information is specified within "{" and "}". The first attribute is the sort element. Leaving it blank means the sort element is the same as the row header element. The attribute "o" means order. Its value can be "a" for ascending, or "d" for descending. The attribute "t" means type. Its value can be "t" for text, and "n" for numeric. There can be more than one sort elements, example: "emp-full-name {emp-lastname,o=a,t=n}{emp-firstname,o=a,t=n}. This will sort employee by last name and first name. "Region{,o=a,t=t}, District{,o=a,t=t}" In the example, the first row header is "Region". It is sort by "Region", order is ascending, and type is text. The second row header is "District". It is sort by "District", order is ascending, and type is text. Columns This contains a list of XML elements for columns headers. The ordering information is specified within "{" and "}". The first attribute is the sort element. Leaving it blank means the sort element is the same as the column header element. The attribute "o" means order. Its value can be "a" for ascending, or "d" for descending. The attribute "t" means type. Its value can be "t" for text, and "n" for numeric. There can be more than one sort elements, example: "emp-full-name {emp-lastname,o=a,t=n}{emp-firstname,o=a,t=n}. This will sort employee by last name and first name. "ProductsBrand{,o=a,t=t}, PeriodYear{,o=a,t=t}" In the example, the first column header is "ProductsBrand". It is sort by "ProductsBrand", order is ascending, and type is text. The second column header is "PeriodYear". It is sort by "District", order is ascending, and type is text. Measures This contains a list of XML elements for measures. "Revenue, PrevRevenue" Aggregation The aggregation function name. Currently, we only support "sum". "sum" Using the Oracle BI Publisher Template Builder for Word add-in, we are able to construct the following Pivot Table: The generated XDO command for this Pivot Table is as follow: <?crosstab:c547; "//ROW";"Region{,o=a,t=t}, District{,o=a,t=t}"; "ProductsBrand{,o=a,t=t},PeriodYear{,o=a,t=t}"; "Revenue, PrevRevenue";"sum"?> Running the command on the give XML data files generates this XML file "cttree.xml". Each XPath in the "cttree.xml" is described in the following table. Element XPath Count Description C0 /cttree/C0 1 This contains elements which are related to column. C1 /cttree/C0/C1 4 The first level column "ProductsBrand". There are four distinct values. They are shown in the label H element. CS /cttree/C0/C1/CS 4 The column-span value. It is used to format the crosstab table. H /cttree/C0/C1/H 4 The column header label. There are four distinct values "Enterprise", "Magicolor", "McCloskey" and "Valspar". T1 /cttree/C0/C1/T1 4 The sum for measure 1, which is Revenue. T2 /cttree/C0/C1/T2 4 The sum for measure 2, which is PrevRevenue. C2 /cttree/C0/C1/C2 8 The first level column "PeriodYear", which is the second group-by key. There are two distinct values "2001" and "2002". H /cttree/C0/C1/C2/H 8 The column header label. There are two distinct values "2001" and "2002". Since it is under C1, therefore the total number of entries is 4 x 2 => 8. T1 /cttree/C0/C1/C2/T1 8 The sum for measure 1 "Revenue". T2 /cttree/C0/C1/C2/T2 8 The sum for measure 2 "PrevRevenue". M0 /cttree/M0 1 This contains elements which are related to measures. M1 /cttree/M0/M1 1 This contains summary for measure 1. H /cttree/M0/M1/H 1 The measure 1 label, which is "Revenue". T /cttree/M0/M1/T 1 The sum of measure 1 for the entire xpath from "//ROW". M2 /cttree/M0/M2 1 This contains summary for measure 2. H /cttree/M0/M2/H 1 The measure 2 label, which is "PrevRevenue". T /cttree/M0/M2/T 1 The sum of measure 2 for the entire xpath from "//ROW". R0 /cttree/R0 1 This contains elements which are related to row. R1 /cttree/R0/R1 4 The first level row "Region". There are four distinct values, they are shown in the label H element. H /cttree/R0/R1/H 4 This is row header label for "Region". There are four distinct values "CENTRAL REGION", "EASTERN REGION", "SOUTHERN REGION" and "WESTERN REGION". RS /cttree/R0/R1/RS 4 The row-span value. It is used to format the crosstab table. T1 /cttree/R0/R1/T1 4 The sum of measure 1 "Revenue" for each distinct "Region" value. T2 /cttree/R0/R1/T2 4 The sum of measure 1 "Revenue" for each distinct "Region" value. R1C1 /cttree/R0/R1/R1C1 16 This contains elements from combining R1 and C1. There are 4 distinct values for "Region", and four distinct values for "ProductsBrand". Therefore, the combination is 4 X 4 è 16. T1 /cttree/R0/R1/R1C1/T1 16 The sum of measure 1 "Revenue" for each combination of "Region" and "ProductsBrand". T2 /cttree/R0/R1/R1C1/T2 16 The sum of measure 2 "PrevRevenue" for each combination of "Region" and "ProductsBrand". R1C2 /cttree/R0/R1/R1C1/R1C2 32 This contains elements from combining R1, C1 and C2. There are 4 distinct values for "Region", and four distinct values for "ProductsBrand", and two distinct values of "PeriodYear". Therefore, the combination is 4 X 4 X 2 è 32. T1 /cttree/R0/R1/R1C1/R1C2/T1 32 The sum of measure 1 "Revenue" for each combination of "Region", "ProductsBrand" and "PeriodYear". T2 /cttree/R0/R1/R1C1/R1C2/T2 32 The sum of measure 2 "PrevRevenue" for each combination of "Region", "ProductsBrand" and "PeriodYear". R2 /cttree/R0/R1/R2 18 This contains elements from combining R1 "Region" and R2 "District". Since the list of values in R2 has dependency on R1, therefore the number of entries is not just a simple multiplication. H /cttree/R0/R1/R2/H 18 The row header label for R2 "District". R1N /cttree/R0/R1/R2/R1N 18 The R2 position number within R1. This is used to check if it is the last row, and draw table border accordingly. T1 /cttree/R0/R1/R2/T1 18 The sum of measure 1 "Revenue" for each combination "Region" and "District". T2 /cttree/R0/R1/R2/T2 18 The sum of measure 2 "PrevRevenue" for each combination of "Region" and "District". R2C1 /cttree/R0/R1/R2/R2C1 72 This contains elements from combining R1, R2 and C1. T1 /cttree/R0/R1/R2/R2C1/T1 72 The sum of measure 1 "Revenue" for each combination of "Region", "District" and "ProductsBrand". T2 /cttree/R0/R1/R2/R2C1/T2 72 The sum of measure 2 "PrevRevenue" for each combination of "Region", "District" and "ProductsBrand". R2C2 /cttree/R0/R1/R2/R2C1/R2C2 144 This contains elements from combining R1, R2, C1 and C2, which gives the finest level of details. M1 /cttree/R0/R1/R2/R2C1/R2C2/M1 144 The sum of measure 1 "Revenue". M2 /cttree/R0/R1/R2/R2C1/R2C2/M2 144 The sum of measure 2 "PrevRevenue". Lots to read and digest I know! Customization One new feature I discovered this week is the ability to show one column and sort by another. I had a data set that was extracting month abbreviations, we wanted to show the months across the top and some row headers to the side. As you may know XSL is not great with dates, especially recognising month names. It just wants to sort them alphabetically, so Apr comes before Jan, etc. A way around this is to generate a month number alongside the month and use that to sort. We can do that in the crosstab, sadly its not exposed in the UI yet but its doable. Go back up and take a look a the initial crosstab command. especially the Rows and Columns entries. In there you will find the sort criteria. "ProductsBrand{,o=a,t=t}, PeriodYear{,o=a,t=t}" Notice those leading commas inside the curly braces? Because there is no field preceding them it means that the crosstab should sort on the column before the brace ie PeriodYear. But you can insert another column in the data set to sort by. To get my sort working how I needed. <?crosstab:c794;"current-group()";"_Fund_Type_._Fund_Type_Display_{_Fund_Type_._Fund_Type_Sort_,o=a,t=n}";"_Fiscal_Period__Amount__._Amt_Fm_Disp_Abbr_{_Fiscal_Period__Amount__._Amt_Fiscal_Month_Sort_,o=a,t=n}";"_Execution_Facts_._Amt_";"sum"?> Excuse the horribly verbose XML tags, good ol BIEE :0) The emboldened columns are not in the crosstab but are in the data set. I just opened up the field, dropped them in and changed the type(t) value to be 'n', for number, instead of the default 'a' and my crosstab started sorting how I wanted it. If you find other tips and tricks, please share in the comments.

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• Facebook require_login() in iFrame App

  - by LapKom

  Hi, I have serious problem with iframe application. I need to use many external JS libraries and other dynamic stuuf so FMBL application can't be done. When I call require_login() I get applicaition installing dialog when app is not already installed, which is ok. But then after authorization application enters an endless redirect loop with parameters like auth_token, installed and so. Yesterday I managed to fix this, but today it's broken again... What the heck is happening with FB? It's driving me crazy to find a sollution, none of ones found on net doesn't seem to be working. So far I tried: http://abhirama.wordpress.com/2010/03/07/facebook-iframe-xfbml-app/ (7th march 2010!) http://forum.developers.facebook.com/viewtopic.php?pid=156092 http://www.keywordintellect.com/facebook-development/how-to-set-up-a-facebook-iframe-application-in-php-in-5-minutes/ http://www.markdeepwell.com/2010/02/validating-a-facebook-session-within-an-iframe/ http://forum.developers.facebook.com/viewtopic.php?pid=210449 http://www.ajaxlines.com/ajax/stuff/article/facebook_fbml_rendering_in_iframe_application.php http://www.aratide.com/php/solving-the-break-out-issue-in-iframe-facebook-applications/ None of the above worked... According to those and some FB docs: http://wiki.developers.facebook.com/index.php/FB_RequireFeatures http://wiki.developers.facebook.com/index.php/Cross_Domain_Communication_Channel My example test files look as follow: <?php //Link in library. require_once '../application/vendor/Facebook/facebook.php'; //Authentication Keys $appapikey = 'XXXX'; $appsecret = 'XXXX'; //Construct the class $facebook = new Facebook($appapikey, $appsecret); //Require login $user_id = $facebook->require_login(); ?> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:fb="http://www.facebook.com/2008/fbml"> <head> <title></title> </head> <body> <script src="http://static.ak.facebook.com/js/api_lib/v0.4/FeatureLoader.js.php" type="text/javascript"></script> This is you: <fb:name uid="<?php echo $user_id?>"></fb:name> <?php var_dump($facebook->$this->facebook->api_client->friends_get())?> <script type="text/javascript"> FB_RequireFeatures(["XFBML"], function(){ FB.Facebook.init("<?=$appapikey?>", "xd_receiver.html"); }); </script> </body> </html> And cross-domain file xd_receiver.html is: <!doctype html public "-//w3c//dtd xhtml 1.0 strict//en" "http://www.w3.org/tr/xhtml1/dtd/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head> <title>cross-domain receiver page</title> </head> <body> <script src="http://static.ak.facebook.com/js/api_lib/v0.4/XdCommReceiver.js" type="text/javascript"></script> </body> </html> How do I get it working? I'm using Kohana framework to do this and already replaced header('Location') with url::redirect() in facebook php library.

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• Restful Services, oData, and Rest Sharp

  - by jkrebsbach

  After a great presentation by Jason Sheehan at MDC about RestSharp, I decided to implement it. RestSharp is a .Net framework for consuming restful data sources via either Json or XML. My first step was to put together a Restful data source for RestSharp to consume.  Staying entirely withing .Net, I decided to use Microsoft's oData implementation, built on System.Data.Services.DataServices.  Natively, these support Json, or atom+pub xml.  (XML with a few bells and whistles added on) There are three main steps for creating an oData data source: 1)  override CreateDSPMetaData This is where the metadata data is returned.  The meta data defines the structure of the data to return.  The structure contains the relationships between data objects, along with what properties the objects expose.  The meta data can and should be somehow cached so that the structure is not rebuild with every data request. 2) override CreateDataSource The context contains the data the data source will publish.  This method is the conduit which will populate the metadata objects to be returned to the requestor. 3) implement static InitializeService At this point we can set up security, along with setting up properties of the web service (versioning, etc)   Here is a web service which publishes stock prices for various Products (stocks) in various Categories. namespace RestService {     public class RestServiceImpl : DSPDataService<DSPContext>     {         private static DSPContext _context;         private static DSPMetadata _metadata;         /// <summary>         /// Populate traversable data source         /// </summary>         /// <returns></returns>         protected override DSPContext CreateDataSource()         {             if (_context == null)             {                 _context = new DSPContext();                 Category utilities = new Category(0);                 utilities.Name = "Electric";                 Category financials = new Category(1);                 financials.Name = "Financial";                                 IList products = _context.GetResourceSetEntities("Products");                 Product electric = new Product(0, utilities);                 electric.Name = "ABC Electric";                 electric.Description = "Electric Utility";                 electric.Price = 3.5;                 products.Add(electric);                 Product water = new Product(1, utilities);                 water.Name = "XYZ Water";                 water.Description = "Water Utility";                 water.Price = 2.4;                 products.Add(water);                 Product banks = new Product(2, financials);                 banks.Name = "FatCat Bank";                 banks.Description = "A bank that's almost too big";                 banks.Price = 19.9; // This will never get to the client                 products.Add(banks);                 IList categories = _context.GetResourceSetEntities("Categories");                 categories.Add(utilities);                 categories.Add(financials);                 utilities.Products.Add(electric);                 utilities.Products.Add(electric);                 financials.Products.Add(banks);             }             return _context;         }         /// <summary>         /// Setup rules describing published data structure - relationships between data,         /// key field, other searchable fields, etc.         /// </summary>         /// <returns></returns>         protected override DSPMetadata CreateDSPMetadata()         {             if (_metadata == null)             {                 _metadata = new DSPMetadata("DemoService", "DataServiceProviderDemo");                 // Define entity type product                 ResourceType product = _metadata.AddEntityType(typeof(Product), "Product");                 _metadata.AddKeyProperty(product, "ProductID");                 // Only add properties we wish to share with end users                 _metadata.AddPrimitiveProperty(product, "Name");                 _metadata.AddPrimitiveProperty(product, "Description");                 EntityPropertyMappingAttribute att = new EntityPropertyMappingAttribute("Name",                     SyndicationItemProperty.Title, SyndicationTextContentKind.Plaintext, true);                 product.AddEntityPropertyMappingAttribute(att);                 att = new EntityPropertyMappingAttribute("Description",                     SyndicationItemProperty.Summary, SyndicationTextContentKind.Plaintext, true);                 product.AddEntityPropertyMappingAttribute(att);                 // Define products as a set of product entities                 ResourceSet products = _metadata.AddResourceSet("Products", product);                 // Define entity type category                 ResourceType category = _metadata.AddEntityType(typeof(Category), "Category");                 _metadata.AddKeyProperty(category, "CategoryID");                 _metadata.AddPrimitiveProperty(category, "Name");                 _metadata.AddPrimitiveProperty(category, "Description");                 // Define categories as a set of category entities                 ResourceSet categories = _metadata.AddResourceSet("Categories", category);                 att = new EntityPropertyMappingAttribute("Name",                     SyndicationItemProperty.Title, SyndicationTextContentKind.Plaintext, true);                 category.AddEntityPropertyMappingAttribute(att);                 att = new EntityPropertyMappingAttribute("Description",                     SyndicationItemProperty.Summary, SyndicationTextContentKind.Plaintext, true);                 category.AddEntityPropertyMappingAttribute(att);                 // A product has a category, a category has products                 _metadata.AddResourceReferenceProperty(product, "Category", categories);                 _metadata.AddResourceSetReferenceProperty(category, "Products", products);             }             return _metadata;         }         /// <summary>         /// Based on the requesting user, can set up permissions to Read, Write, etc.         /// </summary>         /// <param name="config"></param>         public static void InitializeService(DataServiceConfiguration config)         {             config.SetEntitySetAccessRule("*", EntitySetRights.All);             config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2;             config.DataServiceBehavior.AcceptProjectionRequests = true;         }     } }     The objects prefixed with DSP come from the samples on the oData site: http://www.odata.org/developers The products and categories objects are POCO business objects with no special modifiers. Three main options are available for defining the MetaData of data sources in .Net: 1) Generate Entity Data model (Potentially directly from SQL Server database).  This requires the least amount of manual interaction, and uses the edmx WYSIWYG editor to generate a data model.  This can be directly tied to the SQL Server database and generated from the database if you want a data access layer tightly coupled with your database. 2) Object model decorations.  If you already have a POCO data layer, you can decorate your objects with properties to statically inform the compiler how the objects are related.  The disadvantage is there are now tags strewn about your business layer that need to be updated as the business rules change.  3) Programmatically construct metadata object.  This is the object illustrated above in CreateDSPMetaData.  This puts all relationship information into one central programmatic location.  Here business rules are constructed when the DSPMetaData response object is returned.   Once you have your service up and running, RestSharp is designed for XML / Json, along with the native Microsoft library.  There are currently some differences between how Jason made RestSharp expect XML with how atom+pub works, so I found better results currently with the Json implementation - modifying the RestSharp XML parser to make an atom+pub parser is fairly trivial though, so use what implementation works best for you. I put together a sample console app which calls the RestSvcImpl.svc service defined above (and assumes it to be running on port 2000).  I used both RestSharp as a client, and also the default Microsoft oData client tools. namespace RestConsole {     class Program     {         private static DataServiceContext _ctx;         private enum DemoType         {             Xml,             Json         }         static void Main(string[] args)         {             // Microsoft implementation             _ctx = new DataServiceContext(new System.Uri("http://localhost:2000/RestServiceImpl.svc"));             var msProducts = RunQuery<Product>("Products").ToList();             var msCategory = RunQuery<Category>("/Products(0)/Category").AsEnumerable().Single();             var msFilteredProducts = RunQuery<Product>("/Products?$filter=length(Name) ge 4").ToList();             // RestSharp implementation                          DemoType demoType = DemoType.Json;             var client = new RestClient("http://localhost:2000/RestServiceImpl.svc");             client.ClearHandlers(); // Remove all available handlers             // Set up handler depending on what situation dictates             if (demoType == DemoType.Json)                 client.AddHandler("application/json", new RestSharp.Deserializers.JsonDeserializer());             else if (demoType == DemoType.Xml)             {                 client.AddHandler("application/atom+xml", new RestSharp.Deserializers.XmlDeserializer());             }                          var request = new RestRequest();             if (demoType == DemoType.Json)                 request.RootElement = "d"; // service root element for json             else if (demoType == DemoType.Xml)             {                 request.XmlNamespace = "http://www.w3.org/2005/Atom";             }                              // Return all products             request.Resource = "/Products?$orderby=Name";             RestResponse<List<Product>> productsResp = client.Execute<List<Product>>(request);             List<Product> products = productsResp.Data;             // Find category for product with ProductID = 1             request.Resource = string.Format("/Products(1)/Category");             RestResponse<Category> categoryResp = client.Execute<Category>(request);             Category category = categoryResp.Data;             // Specialized queries             request.Resource = string.Format("/Products?$filter=ProductID eq {0}", 1);             RestResponse<Product> productResp = client.Execute<Product>(request);             Product product = productResp.Data;                          request.Resource = string.Format("/Products?$filter=Name eq '{0}'", "XYZ Water");             productResp = client.Execute<Product>(request);             product = productResp.Data;         }         private static IEnumerable<TElement> RunQuery<TElement>(string queryUri)         {             try             {                 return _ctx.Execute<TElement>(new Uri(queryUri, UriKind.Relative));             }             catch (Exception ex)             {                 throw ex;             }         }              } }   Feel free to step through the code a few times and to attach a debugger to the service as well to see how and where the context and metadata objects are constructed and returned.  Pay special attention to the response object being returned by the oData service - There are several properties of the RestRequest that can be used to help troubleshoot when the structure of the response is not exactly what would be expected.

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• Entity Framework many-to-many using VB.Net Lambda

  - by bgs264

  Hello, I'm a newbie to StackOverflow so please be kind ;) I'm using Entity Framework in Visual Studio 2010 Beta 2 (.NET framework 4.0 Beta 2). I have created an entity framework .edmx model from my database and I have a handful of many-to-many relationships. A trivial example of my database schema is Roles (ID, Name, Active) Members (ID, DateOfBirth, DateCreated) RoleMembership(RoleID, MemberID) I am now writing the custom role provider (Inheriting System.Configuration.Provider.RoleProvider) and have come to write the implementation of IsUserInRole(username, roleName). The LINQ-to-Entity queries which I wrote, when SQL-Profiled, all produced CROSS JOIN statements when what I want is for them to INNER JOIN. Dim query = From m In dc.Members From r In dc.Roles Where m.ID = 100 And r.Name = "Member" Select m My problem is almost exactly described here: http://stackoverflow.com/questions/553918/entity-framework-and-many-to-many-queries-unusable I'm sure that the solution presented there works well, but whilst I studied Java at uni and I can mostly understand C# I cannot understand this Lambda syntax provided and I need to get a similar example in VB. I've looked around the web for the best part of half a day but I'm not closer to my answer. So please can somebody advise how, in VB, I can construct a LINQ statement which would do this equivalent in SQL: SELECT rm.RoleID FROM RoleMembership rm INNER JOIN Roles r ON r.ID = rm.RoleID INNER JOIN Members m ON m.ID = rm.MemberID WHERE r.Name = 'Member' AND m.ID = 101 I would use this query to see if Member 101 is in Role 3. (I appreciate I probably don't need the join to the Members table in SQL but I imagine in LINQ I'd need to bring in the Member object?) UPDATE: I'm a bit closer by using multiple methods: Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Dim count As Integer Using dc As New CBLModel.CBLEntities Dim persons = dc.Members.Where(AddressOf myTest) count = persons.Count End Using System.Diagnostics.Debugger.Break() End Sub Function myTest(ByVal m As Member) As Boolean Return m.ID = "100" AndAlso m.Roles.Select(AddressOf myRoleTest).Count > 0 End Function Function myRoleTest(ByVal r As Role) As Boolean Return r.Name = "Member" End Function SQL Profiler shows this: SQL:BatchStarting SELECT [Extent1].[ID] AS [ID], ... (all columns from Members snipped for brevity) ... FROM [dbo].[Members] AS [Extent1] RPC:Completed exec sp_executesql N'SELECT [Extent2].[ID] AS [ID], [Extent2].[Name] AS [Name], [Extent2].[Active] AS [Active] FROM [dbo].[RoleMembership] AS [Extent1] INNER JOIN [dbo].[Roles] AS [Extent2] ON [Extent1].[RoleID] = [Extent2].[ID] WHERE [Extent1].[MemberID] = @EntityKeyValue1',N'@EntityKeyValue1 int',@EntityKeyValue1=100 SQL:BatchCompleted SELECT [Extent1].[ID] AS [ID], ... (all columns from Members snipped for brevity) ... FROM [dbo].[Members] AS [Extent1] I'm not certain why it is using sp_execsql for the inner join statement and why it's still running a select to select ALL members though. Thanks. UPDATE 2 I've written it by turning the above "multiple methods" into lambda expressions then all into one query, like this: Dim allIDs As String = String.Empty Using dc As New CBLModel.CBLEntities For Each retM In dc.Members.Where(Function(m As Member) m.ID = 100 AndAlso m.Roles.Select(Function(r As Role) r.Name = "Doctor").Count > 0) allIDs &= retM.ID.ToString & ";" Next End Using But it doesn't seem to work: "Doctor" is not a role that exists, I just put it in there for testing purposes, yet "allIDs" still gets set to "100;" The SQL in SQL Profiler this time looks like this: SELECT [Project1].* FROM ( SELECT [Extent1].*, (SELECT COUNT(1) AS [A1] FROM [dbo].[RoleMembership] AS [Extent2] WHERE [Extent1].[ID] = [Extent2].[MemberID]) AS [C1] FROM [dbo].[Members] AS [Extent1] ) AS [Project1] WHERE (100 = [Project1].[ID]) AND ([Project1].[C1] > 0) For brevity I turned the list of all the columns from the Members table into * As you can see it's just ignoring the "Role" query... :/

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• Apply jquery selectbox style on chained selectbox

  - by ktsixit

  Hi all, I have created a pair of chained selectboxes in my page. The second selectbox is filled with a set of values, depending on the first box's selected value. The script that makes the two selectboxes work like this, uses php and javascript. This is the code I'm using: form <select name="continent" tabindex="1" onChange="getCountry(this.value)"> <option value="#">-Select-</option> <option value="Europe">Europe</option> <option value="Asia">Asia</option> </select> <div id="countrydiv"> <select name="country" tabindex="2"> <option></option> </select> </div> <input type="submit" /> </form> javascript code $(document).ready(function() { $('select[name="continent"]').selectbox({debug: true}); $('select[name="country"]').selectbox({debug: true}); }); function getXMLHTTP() { //fuction to return the xml http object var xmlhttp=false; try{ xmlhttp=new XMLHttpRequest(); } catch(e) { try{ xmlhttp= new ActiveXObject("Microsoft.XMLHTTP"); } catch(e){ try{ xmlhttp = new ActiveXObject("Msxml2.XMLHTTP"); } catch(e1){ xmlhttp=false; } } } return xmlhttp; } function getCountry(continentId) { var strURL="findCountry.php?continent="+continentId; var req = getXMLHTTP(); if (req) { req.onreadystatechange = function() { if (req.readyState == 4) { // only if "OK" if (req.status == 200) { document.getElementById('countrydiv').innerHTML=req.responseText; } else { alert("There was a problem while using XMLHTTP:\n" + req.statusText); } } } req.open("GET", strURL, true); req.send(null); } } php code (findCountry.php) <? $continent=intval($_GET['continent']); if ($_GET['continent'] == 'Europe') { ?> <select name="country"> <option value="France">France</option> <option value="Germany">Germany</option> <option value="Spain">Spain</option> <option value="Italy">Italy</option> </select> <? } if ($_GET['continent'] == 'Asia') { ?> <select name="country"> <option value="China">China</option> <option value="India">India</option> <option value="Japan">Japan</option> </select> <? } ?> What I want to do is to apply jquery selectbox styling on these selectboxes. I haven't succeeded in doing that yet. The problem is that jquery is hiding the normal selectbox and is replacing it with a list. Furthermore, after selectbox's content is refreshed, jquery cannot re-construct it into a list. You can take a look of the jquery code here Is there something I can do to combine these techniques? I have tried a million things but nothing worked. Can you please help me?

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• Strange WCF Error - IIS hosted - context being aborted

  - by RandomNoob

  I have a WCF service that does some document conversions and returns the document to the caller. When developing locally on my local dev server, the service is hosted on ASP.NET Development server, a console application invokes the operation and executes within seconds. When I host the service in IIS via a .svc file, two of the documents work correctly, the third one bombs out, it begins to construct the word document using the OpenXml Sdk, but then just dies. I think this has something to do with IIS, but I cannot put my finger on it. There are a total of three types of documents I generate. In a nutshell this is how it works SQL 2005 DB/IBM DB2 - WCF Service written by other developer to expose data. This service only has one endpoint using basicHttpBinding My Service invokes his service, gets the relevant data, uses the Open Xml Sdk to generate a Microsoft Word Document, saves it on a server and returns the path to the user. The word documents are no bigger than 100KB. I am also using basicHttpBinding although I have tried wsHttpBinding with the same results. What is amazing is how fast it is locally, and even more that two of the documents generate just fine, its the third document type that refuses to work. To the error message: An error occured while receiving the HTTP Response to http://myservername.mydomain.inc/MyService/Service.Svc. This could be due to the service endpoint binding not using the HTTP Protocol. This could also be due to an HTTP request context being aborted by the server (possibly due to the server shutting down). See server logs for more details. I have spent the last 2 days trying to figure out what is going on, I have tried everything, including changing the maxReceivedMessageSize, maxBufferSize, maxBufferPoolSize, etc etc to large values, I even included: <httpRuntime maxRequestLength="2097151" executionTimeout="120"/> To see maybe if IIS was choking because of that. Programatically the service does nothing special, it just constructs the word documents from the data using the Open Xml Sdk and like I said, locally all 3 documents work when invoked via a console app running locally on the asp.net dev server, i.e. http://localhost:3332/myService.svc When I host it on IIS and I try to get a Windows Forms application to invoke it, I get the error. I know you will ask for logs, so yes I have logging enabled on my Host. And there is no error in the logs, I am logging everything. Basically I invoke two service operations written by another developer. MyOperation calls - HisOperation1 and then HisOperation2, both of those calls give me complex types. I am going to look at his code tomorrow, because he is using LINQ2SQL and there may be some funny business going on there. He is using a variety of collections etc, but the fact that I can run the exact same document, lets call it "Document 3" within seconds when the service is being hosted locally on ASP WebDev Server is what is most odd, why would it run on scaled down Cassini and blow up on IIS? From the log it seems, after calling HisOperation1 and HisOperation2 the service just goes into la-la land dies, there is a application pool (w3wp.exe) error in the Windows Event Log. Faulting application w3wp.exe, version 6.0.3790.1830, stamp 42435be1, faulting module kernel32.dll, version 5.2.3790.3311, stamp 49c5225e, debug? 0, fault address 0x00015dfa. It's classified as .NET 2.0 Runtime error. Any help is appreciated, the lack of sleep is getting to me. Help me Obi-Wan Kenobi, you're my only hope.

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• [python] voice communication for python help!

  - by Eric

  Hello! I'm currently trying to write a voicechat program in python. All tips/trick is welcome to do this. So far I found pyAudio to be a wrapper of PortAudio. So I played around with that and got an input stream from my microphone to be played back to my speakers. Only RAW of course. But I can't send RAW-data over the netowrk (due the size duh), so I'm looking for a way to encode it. And I searched around the 'net and stumbled over this speex-wrapper for python. It seems to good to be true, and believe me, it was. You see in pyAudio you can set the size of the chunks you want to take from your input audiobuffer, and in that sample code on the link, it's set to 320. Then when it's encoded, its like ~40 bytes of data per chunk, which is fairly acceptable I guess. And now for the problem. I start a sample program which just takes the input stream, encodes the chunks, decodes them and play them (not sending over the network due testing). If I just let my computer idle and run this program it works great, but as soon as I do something, i.e start Firefox or something, the audio input buffer gets all clogged up! It just grows and then it all crashes and gives me an overflow error on the buffer.. OK, so why am I just taking 320 bytes of the stream? I could just take like 1024 bytes or something and that will easy the pressure on the buffer. BUT. If I give speex 1024 bytes of data to encode/decode, it either crashes and says that thats too big for its buffer. OR it encodes/decodes it, but the sound is very noisy and "choppy" as if it only encoded a tiny bit of that 1024 chunk and the rest is static noise. So the sound sounds like a helicopter, lol. I did some research and it seems that speex only can convert 320 bytes of data at time, and well, 640 for wide-band. But that's the standard? How can I fix this problem? How should I construct my program to work with speex? I could use a middle-buffer tho that takes all available data to read from the buffer, then chunk this up in 320 bits and encode/decode them. But this takes a bit longer time and seems like a very bad solution of the problem.. Because as far as I know, there's no other encoder for python that encodes the audio so it can be sent over the network in acceptable small packages, or? I've been googling for three days now. Also there is this pyMedia library, I don't know if its good to convert to mp3/ogg for this kind of software. Thank in in advance for reading this, hope anyone can help me! (:

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• Provider<HttpSession> not getting injected

  - by user1033715

  I am using gwt dispatch to communicate and get data from server to client. In order to get user specific data I want to store the user object in httpsession and access application specific data from servlet context but when I inject Provider<HttpSession> when the handler execute is called but the dispatchservlet the provider is null i.e it does not get injected. following is the code from my action handler @Inject Provider<HttpSession> provider; public ReadEntityHandler() { } @Override public EntityResult execute(ReadEntityAction arg0, ExecutionContext arg1) throws DispatchException { HttpSession session = null; if (provider == null) System.out.println("httpSession is null.."); else { session = provider.get(); System.out.println("httpSession not null.."); } System.out.println("reached execution"); return null; } and my Dispatch servlet @Singleton public class ActionDispatchServlet extends RemoteServiceServlet implements StandardDispatchService { private Dispatch dispatch; public ActionDispatchServlet() { InstanceActionHandlerRegistry registry = new DefaultActionHandlerRegistry(); registry.addHandler(new ReadEntityHandler()); dispatch = new SimpleDispatch(registry); } @Override public Result execute(Action<?> action) throws DispatchException { try { return dispatch.execute(action); } catch (RuntimeException e) { log("Exception while executing " + action.getClass().getName() + ": " + e.getMessage(), e); throw e; } } } when I try to inject the ReadEntityHandler it throws the following exception [WARN] failed guiceFilter com.google.inject.ProvisionException: Guice provision errors: 1) Error injecting constructor, java.lang.NullPointerException at com.ensarm.wikirealty.server.service.ActionDispatchServlet.<init>(ActionDispatchServlet.java:22) at com.ensarm.wikirealty.server.service.ActionDispatchServlet.class(ActionDispatchServlet.java:22) while locating com.ensarm.wikirealty.server.service.ActionDispatchServlet 1 error at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:834) at com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:856) at com.google.inject.servlet.ServletDefinition.init(ServletDefinition.java:74) at com.google.inject.servlet.ManagedServletPipeline.init(ManagedServletPipeline.java:84) at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:106) at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:168) at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593) at org.mortbay.jetty.servlet.Context.startContext(Context.java:140) at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220) at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448) at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130) at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130) at org.mortbay.jetty.Server.doStart(Server.java:222) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672) at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509) at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068) at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811) at com.google.gwt.dev.DevMode.main(DevMode.java:311) Caused by: java.lang.NullPointerException at net.customware.gwt.dispatch.server.DefaultActionHandlerRegistry.addHandler(DefaultActionHandlerRegistry.java:21) at com.ensarm.wikirealty.server.service.ActionDispatchServlet.<init>(ActionDispatchServlet.java:24) at com.ensarm.wikirealty.server.service.ActionDispatchServlet$$FastClassByGuice$$e0a28a5d.newInstance(<generated>) at com.google.inject.internal.cglib.reflect.FastConstructor.newInstance(FastConstructor.java:40) at com.google.inject.internal.DefaultConstructionProxyFactory$1.newInstance(DefaultConstructionProxyFactory.java:58) at com.google.inject.internal.ConstructorInjector.construct(ConstructorInjector.java:84) at com.google.inject.internal.ConstructorBindingImpl$Factory.get(ConstructorBindingImpl.java:200) at com.google.inject.internal.ProviderToInternalFactoryAdapter$1.call(ProviderToInternalFactoryAdapter.java:43) at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:878) at com.google.inject.internal.ProviderToInternalFactoryAdapter.get(ProviderToInternalFactoryAdapter.java:40) at com.google.inject.Scopes$1$1.get(Scopes.java:64) at com.google.inject.internal.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:40) at com.google.inject.internal.InjectorImpl$4$1.call(InjectorImpl.java:825) at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:871) at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:821) ... 25 more

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• Improving the performance of XSL

  - by Rachel

  In the below XSL for the variable "insert-data", I have an input param with the structure, <insert-data> <data compareIndex="4" nodeName="d1e1"> <a/> </data> <data compareIndex="5" nodeName="d1e1"> <b/> </data> <data compareIndex="7" nodeName="d1e2"> <a/> </data> <data compareIndex="9" nodeName="d1e2"> <b/> </data> </insert-data> where "nodeName" is the id of a node and "compareIndex" is the position of the text content relative to the node having id "$nodeName". I am using the below XSL to select all the text nodes(generate-id) that satisfy the above condition and construct a data xml. The below implementation works perfectly but the time taken for the execution is in min. Is there a better way of implementing or is there any in-efficient operation being used. From my observation the code where the preceding text length is calculated consumes the major time. Please share your thoughts to improve the performance of the XSL. I am using Java SAXON XSL transformer. <xsl:variable name="insert-data" as="element()*"> <xsl:for-each select="$insert-file/insert-data/data"> <xsl:sort select="xsd:integer(@index)"/> <xsl:variable name="compareIndex" select="xsd:integer(@compareIndex)" /> <xsl:variable name="nodeName" select="@nodeName" /> <xsl:variable name="nodeContent" as="node()"> <xsl:copy-of select="node()"/> </xsl:variable> <xsl:for-each select="$main-root/*//text()[ancestor::*[@id = $nodeName]]"> <xsl:variable name="preTextLength" as="xsd:integer" select="sum((preceding::text())[. ancestor::*[@id = $nodeName]]/string-length(.))" /> <xsl:variable name="currentTextLength" as="xsd:integer" select="string-length(.)" /> <xsl:variable name="sum" select="$preTextLength + $currentTextLength" as="xsd:integer"></xsl:variable> <xsl:variable name="split-index" select="$compareIndex - $preTextLength" as="xsd:integer"></xsl:variable> <xsl:if test="($sum ge $compareIndex) and ($compareIndex gt $preTextLength)"> <data split-index="{$split-index}" text-id="{generate-id(.)}"> <xsl:copy-of select="$nodeContent"/> </data> </xsl:if> </xsl:for-each> </xsl:for-each> </xsl:variable>

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• Spooling in SQL execution plans

  - by Rob Farley

  Sewing has never been my thing. I barely even know the terminology, and when discussing this with American friends, I even found out that half the words that Americans use are different to the words that English and Australian people use. That said – let’s talk about spools! In particular, the Spool operators that you find in some SQL execution plans. This post is for T-SQL Tuesday, hosted this month by me! I’ve chosen to write about spools because they seem to get a bad rap (even in my song I used the line “There’s spooling from a CTE, they’ve got recursion needlessly”). I figured it was worth covering some of what spools are about, and hopefully explain why they are remarkably necessary, and generally very useful. If you have a look at the Books Online page about Plan Operators, at http://msdn.microsoft.com/en-us/library/ms191158.aspx, and do a search for the word ‘spool’, you’ll notice it says there are 46 matches. 46! Yeah, that’s what I thought too... Spooling is mentioned in several operators: Eager Spool, Lazy Spool, Index Spool (sometimes called a Nonclustered Index Spool), Row Count Spool, Spool, Table Spool, and Window Spool (oh, and Cache, which is a special kind of spool for a single row, but as it isn’t used in SQL 2012, I won’t describe it any further here). Spool, Table Spool, Index Spool, Window Spool and Row Count Spool are all physical operators, whereas Eager Spool and Lazy Spool are logical operators, describing the way that the other spools work. For example, you might see a Table Spool which is either Eager or Lazy. A Window Spool can actually act as both, as I’ll mention in a moment. In sewing, cotton is put onto a spool to make it more useful. You might buy it in bulk on a cone, but if you’re going to be using a sewing machine, then you quite probably want to have it on a spool or bobbin, which allows it to be used in a more effective way. This is the picture that I want you to think about in relation to your data. I’m sure you use spools every time you use your sewing machine. I know I do. I can’t think of a time when I’ve got out my sewing machine to do some sewing and haven’t used a spool. However, I often run SQL queries that don’t use spools. You see, the data that is consumed by my query is typically in a useful state without a spool. It’s like I can just sew with my cotton despite it not being on a spool! Many of my favourite features in T-SQL do like to use spools though. This looks like a very similar query to before, but includes an OVER clause to return a column telling me the number of rows in my data set. I’ll describe what’s going on in a few paragraphs’ time. So what does a Spool operator actually do? The spool operator consumes a set of data, and stores it in a temporary structure, in the tempdb database. This structure is typically either a Table (ie, a heap), or an Index (ie, a b-tree). If no data is actually needed from it, then it could also be a Row Count spool, which only stores the number of rows that the spool operator consumes. A Window Spool is another option if the data being consumed is tightly linked to windows of data, such as when the ROWS/RANGE clause of the OVER clause is being used. You could maybe think about the type of spool being like whether the cotton is going onto a small bobbin to fit in the base of the sewing machine, or whether it’s a larger spool for the top. A Table or Index Spool is either Eager or Lazy in nature. Eager and Lazy are Logical operators, which talk more about the behaviour, rather than the physical operation. If I’m sewing, I can either be all enthusiastic and get all my cotton onto the spool before I start, or I can do it as I need it. “Lazy” might not the be the best word to describe a person – in the SQL world it describes the idea of either fetching all the rows to build up the whole spool when the operator is called (Eager), or populating the spool only as it’s needed (Lazy). Window Spools are both physical and logical. They’re eager on a per-window basis, but lazy between windows. And when is it needed? The way I see it, spools are needed for two reasons. 1 – When data is going to be needed AGAIN. 2 – When data needs to be kept away from the original source. If you’re someone that writes long stored procedures, you are probably quite aware of the second scenario. I see plenty of stored procedures being written this way – where the query writer populates a temporary table, so that they can make updates to it without risking the original table. SQL does this too. Imagine I’m updating my contact list, and some of my changes move data to later in the book. If I’m not careful, I might update the same row a second time (or even enter an infinite loop, updating it over and over). A spool can make sure that I don’t, by using a copy of the data. This problem is known as the Halloween Effect (not because it’s spooky, but because it was discovered in late October one year). As I’m sure you can imagine, the kind of spool you’d need to protect against the Halloween Effect would be eager, because if you’re only handling one row at a time, then you’re not providing the protection... An eager spool will block the flow of data, waiting until it has fetched all the data before serving it up to the operator that called it. In the query below I’m forcing the Query Optimizer to use an index which would be upset if the Name column values got changed, and we see that before any data is fetched, a spool is created to load the data into. This doesn’t stop the index being maintained, but it does mean that the index is protected from the changes that are being done. There are plenty of times, though, when you need data repeatedly. Consider the query I put above. A simple join, but then counting the number of rows that came through. The way that this has executed (be it ideal or not), is to ask that a Table Spool be populated. That’s the Table Spool operator on the top row. That spool can produce the same set of rows repeatedly. This is the behaviour that we see in the bottom half of the plan. In the bottom half of the plan, we see that the a join is being done between the rows that are being sourced from the spool – one being aggregated and one not – producing the columns that we need for the query. Table v Index When considering whether to use a Table Spool or an Index Spool, the question that the Query Optimizer needs to answer is whether there is sufficient benefit to storing the data in a b-tree. The idea of having data in indexes is great, but of course there is a cost to maintaining them. Here we’re creating a temporary structure for data, and there is a cost associated with populating each row into its correct position according to a b-tree, as opposed to simply adding it to the end of the list of rows in a heap. Using a b-tree could even result in page-splits as the b-tree is populated, so there had better be a reason to use that kind of structure. That all depends on how the data is going to be used in other parts of the plan. If you’ve ever thought that you could use a temporary index for a particular query, well this is it – and the Query Optimizer can do that if it thinks it’s worthwhile. It’s worth noting that just because a Spool is populated using an Index Spool, it can still be fetched using a Table Spool. The details about whether or not a Spool used as a source shows as a Table Spool or an Index Spool is more about whether a Seek predicate is used, rather than on the underlying structure. Recursive CTE I’ve already shown you an example of spooling when the OVER clause is used. You might see them being used whenever you have data that is needed multiple times, and CTEs are quite common here. With the definition of a set of data described in a CTE, if the query writer is leveraging this by referring to the CTE multiple times, and there’s no simplification to be leveraged, a spool could theoretically be used to avoid reapplying the CTE’s logic. Annoyingly, this doesn’t happen. Consider this query, which really looks like it’s using the same data twice. I’m creating a set of data (which is completely deterministic, by the way), and then joining it back to itself. There seems to be no reason why it shouldn’t use a spool for the set described by the CTE, but it doesn’t. On the other hand, if we don’t pull as many columns back, we might see a very different plan. You see, CTEs, like all sub-queries, are simplified out to figure out the best way of executing the whole query. My example is somewhat contrived, and although there are plenty of cases when it’s nice to give the Query Optimizer hints about how to execute queries, it usually doesn’t do a bad job, even without spooling (and you can always use a temporary table). When recursion is used, though, spooling should be expected. Consider what we’re asking for in a recursive CTE. We’re telling the system to construct a set of data using an initial query, and then use set as a source for another query, piping this back into the same set and back around. It’s very much a spool. The analogy of cotton is long gone here, as the idea of having a continual loop of cotton feeding onto a spool and off again doesn’t quite fit, but that’s what we have here. Data is being fed onto the spool, and getting pulled out a second time when the spool is used as a source. (This query is running on AdventureWorks, which has a ManagerID column in HumanResources.Employee, not AdventureWorks2012) The Index Spool operator is sucking rows into it – lazily. It has to be lazy, because at the start, there’s only one row to be had. However, as rows get populated onto the spool, the Table Spool operator on the right can return rows when asked, ending up with more rows (potentially) getting back onto the spool, ready for the next round. (The Assert operator is merely checking to see if we’ve reached the MAXRECURSION point – it vanishes if you use OPTION (MAXRECURSION 0), which you can try yourself if you like). Spools are useful. Don’t lose sight of that. Every time you use temporary tables or table variables in a stored procedure, you’re essentially doing the same – don’t get upset at the Query Optimizer for doing so, even if you think the spool looks like an expensive part of the query. I hope you’re enjoying this T-SQL Tuesday. Why not head over to my post that is hosting it this month to read about some other plan operators? At some point I’ll write a summary post – once I have you should find a comment below pointing at it. @rob_farley

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• Convert ddply {plyr} to Oracle R Enterprise, or use with Embedded R Execution

  - by Mark Hornick

  The plyr package contains a set of tools for partitioning a problem into smaller sub-problems that can be more easily processed. One function within {plyr} is ddply, which allows you to specify subsets of a data.frame and then apply a function to each subset. The result is gathered into a single data.frame. Such a capability is very convenient. The function ddply also has a parallel option that if TRUE, will apply the function in parallel, using the backend provided by foreach. This type of functionality is available through Oracle R Enterprise using the ore.groupApply function. In this blog post, we show a few examples from Sean Anderson's "A quick introduction to plyr" to illustrate the correpsonding functionality using ore.groupApply. To get started, we'll create a demo data set and load the plyr package. set.seed(1) d <- data.frame(year = rep(2000:2014, each = 3),         count = round(runif(45, 0, 20))) dim(d) library(plyr) This first example takes the data frame, partitions it by year, and calculates the coefficient of variation of the count, returning a data frame. # Example 1 res <- ddply(d, "year", function(x) {   mean.count <- mean(x$count)   sd.count <- sd(x$count)   cv <- sd.count/mean.count   data.frame(cv.count = cv)   }) To illustrate the equivalent functionality in Oracle R Enterprise, using embedded R execution, we use the ore.groupApply function on the same data, but pushed to the database, creating an ore.frame. The function ore.push creates a temporary table in the database, returning a proxy object, the ore.frame. D <- ore.push(d) res <- ore.groupApply (D, D$year, function(x) {   mean.count <- mean(x$count)   sd.count <- sd(x$count)   cv <- sd.count/mean.count   data.frame(year=x$year[1], cv.count = cv)   }, FUN.VALUE=data.frame(year=1, cv.count=1)) You'll notice the similarities in the first three arguments. With ore.groupApply, we augment the function to return the specific data.frame we want. We also specify the argument FUN.VALUE, which describes the resulting data.frame. From our previous blog posts, you may recall that by default, ore.groupApply returns an ore.list containing the results of each function invocation. To get a data.frame, we specify the structure of the result. The results in both cases are the same, however the ore.groupApply result is an ore.frame. In this case the data stays in the database until it's actually required. This can result in significant memory and time savings whe data is large. R> class(res) [1] "ore.frame" attr(,"package") [1] "OREbase" R> head(res)    year cv.count 1 2000 0.3984848 2 2001 0.6062178 3 2002 0.2309401 4 2003 0.5773503 5 2004 0.3069680 6 2005 0.3431743 To make the ore.groupApply execute in parallel, you can specify the argument parallel with either TRUE, to use default database parallelism, or to a specific number, which serves as a hint to the database as to how many parallel R engines should be used. The next ddply example uses the summarise function, which creates a new data.frame. In ore.groupApply, the year column is passed in with the data. Since no automatic creation of columns takes place, we explicitly set the year column in the data.frame result to the value of the first row, since all rows received by the function have the same year. # Example 2 ddply(d, "year", summarise, mean.count = mean(count)) res <- ore.groupApply (D, D$year, function(x) {   mean.count <- mean(x$count)   data.frame(year=x$year[1], mean.count = mean.count)   }, FUN.VALUE=data.frame(year=1, mean.count=1)) R> head(res)    year mean.count 1 2000 7.666667 2 2001 13.333333 3 2002 15.000000 4 2003 3.000000 5 2004 12.333333 6 2005 14.666667 Example 3 uses the transform function with ddply, which modifies the existing data.frame. With ore.groupApply, we again construct the data.frame explicilty, which is returned as an ore.frame. # Example 3 ddply(d, "year", transform, total.count = sum(count)) res <- ore.groupApply (D, D$year, function(x) {   total.count <- sum(x$count)   data.frame(year=x$year[1], count=x$count, total.count = total.count)   }, FUN.VALUE=data.frame(year=1, count=1, total.count=1)) > head(res)    year count total.count 1 2000 5 23 2 2000 7 23 3 2000 11 23 4 2001 18 40 5 2001 4 40 6 2001 18 40 In Example 4, the mutate function with ddply enables you to define new columns that build on columns just defined. Since the construction of the data.frame using ore.groupApply is explicit, you always have complete control over when and how to use columns. # Example 4 ddply(d, "year", mutate, mu = mean(count), sigma = sd(count),       cv = sigma/mu) res <- ore.groupApply (D, D$year, function(x) {   mu <- mean(x$count)   sigma <- sd(x$count)   cv <- sigma/mu   data.frame(year=x$year[1], count=x$count, mu=mu, sigma=sigma, cv=cv)   }, FUN.VALUE=data.frame(year=1, count=1, mu=1,sigma=1,cv=1)) R> head(res)    year count mu sigma cv 1 2000 5 7.666667 3.055050 0.3984848 2 2000 7 7.666667 3.055050 0.3984848 3 2000 11 7.666667 3.055050 0.3984848 4 2001 18 13.333333 8.082904 0.6062178 5 2001 4 13.333333 8.082904 0.6062178 6 2001 18 13.333333 8.082904 0.6062178 In Example 5, ddply is used to partition data on multiple columns before constructing the result. Realizing this with ore.groupApply involves creating an index column out of the concatenation of the columns used for partitioning. This example also allows us to illustrate using the ORE transparency layer to subset the data. # Example 5 baseball.dat <- subset(baseball, year > 2000) # data from the plyr package x <- ddply(baseball.dat, c("year", "team"), summarize,            homeruns = sum(hr)) We first push the data set to the database to get an ore.frame. We then add the composite column and perform the subset, using the transparency layer. Since the results from database execution are unordered, we will explicitly sort these results and view the first 6 rows. BB.DAT <- ore.push(baseball) BB.DAT$index <- with(BB.DAT, paste(year, team, sep="+")) BB.DAT2 <- subset(BB.DAT, year > 2000) X <- ore.groupApply (BB.DAT2, BB.DAT2$index, function(x) {   data.frame(year=x$year[1], team=x$team[1], homeruns=sum(x$hr))   }, FUN.VALUE=data.frame(year=1, team="A", homeruns=1), parallel=FALSE) res <- ore.sort(X, by=c("year","team")) R> head(res)    year team homeruns 1 2001 ANA 4 2 2001 ARI 155 3 2001 ATL 63 4 2001 BAL 58 5 2001 BOS 77 6 2001 CHA 63 Our next example is derived from the ggplot function documentation. This illustrates the use of ddply within using the ggplot2 package. We first create a data.frame with demo data and use ddply to create some statistics for each group (gp). We then use ggplot to produce the graph. We can take this same code, push the data.frame df to the database and invoke this on the database server. The graph will be returned to the client window, as depicted below. # Example 6 with ggplot2 library(ggplot2) df <- data.frame(gp = factor(rep(letters[1:3], each = 10)),                  y = rnorm(30)) # Compute sample mean and standard deviation in each group library(plyr) ds <- ddply(df, .(gp), summarise, mean = mean(y), sd = sd(y)) # Set up a skeleton ggplot object and add layers: ggplot() +   geom_point(data = df, aes(x = gp, y = y)) +   geom_point(data = ds, aes(x = gp, y = mean),              colour = 'red', size = 3) +   geom_errorbar(data = ds, aes(x = gp, y = mean,                                ymin = mean - sd, ymax = mean + sd),              colour = 'red', width = 0.4) DF <- ore.push(df) ore.tableApply(DF, function(df) {   library(ggplot2)   library(plyr)   ds <- ddply(df, .(gp), summarise, mean = mean(y), sd = sd(y))   ggplot() +     geom_point(data = df, aes(x = gp, y = y)) +     geom_point(data = ds, aes(x = gp, y = mean),                colour = 'red', size = 3) +     geom_errorbar(data = ds, aes(x = gp, y = mean,                                  ymin = mean - sd, ymax = mean + sd),                   colour = 'red', width = 0.4) }) But let's take this one step further. Suppose we wanted to produce multiple graphs, partitioned on some index column. We replicate the data three times and add some noise to the y values, just to make the graphs a little different. We also create an index column to form our three partitions. Note that we've also specified that this should be executed in parallel, allowing Oracle Database to control and manage the server-side R engines. The result of ore.groupApply is an ore.list that contains the three graphs. Each graph can be viewed by printing the list element. df2 <- rbind(df,df,df) df2$y <- df2$y + rnorm(nrow(df2)) df2$index <- c(rep(1,300), rep(2,300), rep(3,300)) DF2 <- ore.push(df2) res <- ore.groupApply(DF2, DF2$index, function(df) {   df <- df[,1:2]   library(ggplot2)   library(plyr)   ds <- ddply(df, .(gp), summarise, mean = mean(y), sd = sd(y))   ggplot() +     geom_point(data = df, aes(x = gp, y = y)) +     geom_point(data = ds, aes(x = gp, y = mean),                colour = 'red', size = 3) +     geom_errorbar(data = ds, aes(x = gp, y = mean,                                  ymin = mean - sd, ymax = mean + sd),                   colour = 'red', width = 0.4)   }, parallel=TRUE) res[[1]] res[[2]] res[[3]] To recap, we've illustrated how various uses of ddply from the plyr package can be realized in ore.groupApply, which affords the user explicit control over the contents of the data.frame result in a straightforward manner. We've also highlighted how ddply can be used within an ore.groupApply call.

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• ASP.NET: Using conditionals in data binding expressions

  - by DigiMortal

  ASP.NET 2.0 has no support for using conditionals in data binding expressions but it will change in ASP.NET 4.0. In this posting I will show you how to implement Iif() function for ASP.NET 2.0 and how ASP.NET 4.0 solves this problem smoothly without any code. Problem Let’s say we have simple repeater. <asp:Repeater runat="server" ID="itemsList">     <HeaderTemplate>         <table border="1" cellspacing="0" cellpadding="5">     </HeaderTemplate>     <ItemTemplate>         <tr>         <td align="right"><%# Container.ItemIndex + 1 %>.</td>         <td><%# Eval("Title") %></td>         </tr>     </ItemTemplate>     <FooterTemplate>         </table>     </FooterTemplate> </asp:Repeater> Repeater is bound to data when form loads. protected void Page_Load(object sender, EventArgs e) {     var items = new[] {                     new { Id = 1, Title = "Headline 1" },                     new { Id = 2, Title = "Headline 2" },                     new { Id = 2, Title = "Headline 3" },                     new { Id = 2, Title = "Headline 4" },                     new { Id = 2, Title = "Headline 5" }                 };     itemsList.DataSource = items;     itemsList.DataBind(); } We need to format even and odd rows differently. Let’s say we want even rows to be with whitesmoke background and odd rows with white background. Just like shown on screenshot on right. Our first thought is to use some simple expression to avoid writing custom methods. We cannot use construct like this <%# Container.ItemIndex % 2==0 ? "white" : "whitesmoke"  %> because all we get are template compilation errors. ASP.NET 2.0: Iif() method For ASP.NET 2.0 pages and controls we can create Iif() method and call it from our templates. This is out Iif() method. protected object Iif(bool condition, object trueResult, object falseResult) {     return condition ? trueResult : falseResult; } And here you can see how to use it. <asp:Repeater runat="server" ID="itemsList">   <HeaderTemplate>     <table border="1" cellspacing="0" cellpadding="5">     </HeaderTemplate>   <ItemTemplate>     <tr style='background-color:'       <%# Iif(Container.ItemIndex % 2==0 ? "white" : "whitesmoke") %>'>       <td align="right">         <%# Container.ItemIndex + 1 %>.</td>       <td>         <%# Eval("Title") %></td>     </tr>   </ItemTemplate>   <FooterTemplate>     </table>   </FooterTemplate> </asp:Repeater> This method does not care about types because it works with all objects (and value-types). I had to define this method in code-behind file of my user control because using this method as extension method made it undetectable for ASP.NET template engine. ASP.NET 4.0: Conditionals are supported In ASP.NET 4.0 we will write … hmm … we will write nothing special. Here is solution. <asp:Repeater runat="server" ID="itemsList">   <HeaderTemplate>     <table border="1" cellspacing="0" cellpadding="5">     </HeaderTemplate>   <ItemTemplate>     <tr style='background-color:'       <%# Container.ItemIndex % 2==0 ? "white" : "whitesmoke" %>'>       <td align="right">         <%# Container.ItemIndex + 1 %>.</td>       <td>         <%# Eval("Title") %></td>     </tr>   </ItemTemplate>   <FooterTemplate>     </table>   </FooterTemplate> </asp:Repeater> Yes, it works well. :)

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• multiple valgrind errors: Conditional jump or move depends on uninitialised value(s)

  - by Hristo

  I'm running valgrind and I'm getting the following error (this is not the only one): ==21743== Conditional jump or move depends on uninitialised value(s) ==21743== at 0x4A06509: index (mc_replace_strmem.c:164) ==21743== by 0x33B7CBB3CD: gaih_inet (in /lib64/libc-2.5.so) ==21743== by 0x33B7CBD629: getaddrinfo (in /lib64/libc-2.5.so) ==21743== by 0x401A5F: tunnelURL (proxy.c:336) ==21743== by 0x40142A: client_thread (proxy.c:194) ==21743== by 0x33B8806616: start_thread (in /lib64/libpthread-2.5.so) ==21743== by 0x33B7CD3C2C: clone (in /lib64/libc-2.5.so) My tunnelURL() function looks like this: char * tunnelURL(char *url) { char * a = strstr(url, "//"); a += 2; char * path = strstr(a, "/"); char host[256]; strncpy (host, a, strlen(a)-strlen(path)); /* * The following is courtesy of Beej's Guide */ int status; int proxySocketFD; struct addrinfo hints; struct addrinfo *servinfo; // will point to the results memset(&hints, 0, sizeof(hints)); // make sure the struct is empty hints.ai_family = AF_INET; // don't care IPv4 or IPv6 hints.ai_socktype = SOCK_STREAM; // TCP stream sockets hints.ai_flags = AI_PASSIVE; // fill in my IP for me if ((status = getaddrinfo(host, "80", &hints, &servinfo)) != 0) { perror("getaddrinfo() fail"); exit(1); } // create socket if ((proxySocketFD = socket(servinfo->ai_family, servinfo->ai_socktype, servinfo->ai_protocol)) == -1) { perror("proxy socket() fail"); exit(1); } // connect if (connect(proxySocketFD, servinfo->ai_addr, servinfo->ai_addrlen) != 0) { printf("connect() fail"); exit(1); } // construct request char request[strlen(path) + strlen(host) + 26]; sprintf(request, "GET %s HTTP/1.1\r\nHost: %s\r\n\r\n", path, host); printf("%s", request); // send request send(proxySocketFD, request, strlen(request), 0); // receive response int i = 0; int amntRecvd = 0; char *pageContentBuffer = (char*) malloc(4096 * sizeof(char)); while ((amntRecvd = recv(proxySocketFD, pageContentBuffer + i, 4096, 0)) > 0) { i += amntRecvd; realloc(pageContentBuffer, i * 4096 * sizeof(char)); } // close proxy socket close(proxySocketFD); // deallocate memory freeaddrinfo(servinfo); return pageContentBuffer; } Line 336 corresponds to the if statement with the getaddrinfo() function call. I'm not really sure what I haven't initialized. The string I'm passing in "should" be already set... I'm printing it out just fine. I also get another error corresponding to the same line of code: ==21743== Use of uninitialised value of size 8 ==21743== at 0x33B7D05816: __nscd_cache_search (in /lib64/libc-2.5.so) ==21743== by 0x33B7D0438B: nscd_gethst_r (in /lib64/libc-2.5.so) ==21743== by 0x33B7D04B26: __nscd_gethostbyname2_r (in /lib64/libc-2.5.so) ==21743== by 0x33B7CE9F5E: gethostbyname2_r@@GLIBC_2.2.5 (in /lib64/libc-2.5.so) ==21743== by 0x33B7CBC522: gaih_inet (in /lib64/libc-2.5.so) ==21743== by 0x33B7CBD629: getaddrinfo (in /lib64/libc-2.5.so) ==21743== by 0x401A5F: tunnelURL (proxy.c:336) ==21743== by 0x40142A: client_thread (proxy.c:194) ==21743== by 0x33B8806616: start_thread (in /lib64/libpthread-2.5.so) ==21743== by 0x33B7CD3C2C: clone (in /lib64/libc-2.5.so) Any ideas as to what might becausing this? This is written in C btw... Thanks, Hristo

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• Firefox not running jQuery for XHTML output

  - by ScottSEA

  Okay, I did a crappy job of describing the issue in my previous post. I think the discussion got sidetracked from the core issue - so I'm going to try again. Mea Culpa to Elzo Valugi about the aforementioned thread. I have an XML file: <?xml version="1.0" encoding="utf-8"?> <?xml-stylesheet type="text/xsl" href="wtf.xsl"?> <Paragraphs> <Paragraph>Hi</Paragraph> </Paragraphs> Simple enough. I also have a stylesheet to create XHTML output: <?xml version="1.0" encoding="utf-8"?> <xsl:stylesheet version="1.0" xmlns="http://www.w3.org/1999/xhtml" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="xml" indent="yes" doctype-system="http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" doctype-public="-//W3C//DTD XHTML 1.0 Transitional//EN" omit-xml-declaration="yes"/> <xsl:template match="/*"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <title>FF-JS-XHTML WTF</title> <script type="text/javascript" src="jquery.js"></script> <script type="text/javascript" src="wtf.js"></script> </head> <body> <xsl:apply-templates /> </body> </html> </xsl:template> <xsl:template match="Paragraph"> <p> <xsl:apply-templates /> </p> </xsl:template> </xsl:stylesheet> Last but not least, I have the following jQuery in toto (wtf.js, from the script tag in the stylesheet): $(function() { alert('Hiya!'); $('<p>Hello</p>').appendTo('body'); }); Extremely simple, but sufficient for the demonstration. When I run this in Internet Explorer, I get the alert 'Hiya!' as well as the expected: Hi Hello but when I run it in Firefox (3.0.1), I still get the alert, but the jQuery does not insert the paragraph into the DOM, and I just get this: Hi If I change the stylesheet to method="html" it works fine, and I get (along with the alert): Hi Hello Why doesn't Firefox run the jQuery with an XHTML document? Has anyone any experience with this problem? EDIT: ADDITIONAL INFO I can successfully insert elements into the documents this way in Firefox (method="xml"): var frag = document.createDocumentFragment(); var p = document.createElement('p'); p.appendChild(document.createTextNode('Ipsum Lorem')); frag.appendChild(p); $('body').append(frag); but I'm running into a similar problem with the .remove() method. It is looking more and more that Firefox doesn't construct a DOM from XML that jQuery can relate to, or somesuch.

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• bind() fails with windows socket error 10038

  - by herrturtur

  I'm trying to write a simple program that will receive a string of max 20 characters and print that string to the screen. The code compiles, but I get a bind() failed: 10038. After looking up the error number on msdn (socket operation on nonsocket), I changed some code from int sock; to SOCKET sock which shouldn't make a difference, but one never knows. Here's the code: #include <iostream> #include <winsock2.h> #include <cstdlib> using namespace std; const int MAXPENDING = 5; const int MAX_LENGTH = 20; void DieWithError(char *errorMessage); int main(int argc, char **argv) { if(argc!=2){ cerr << "Usage: " << argv[0] << " <Port>" << endl; exit(1); } // start winsock2 library WSAData wsaData; if(WSAStartup(MAKEWORD(2,0), &wsaData)!=0){ cerr << "WSAStartup() failed" << endl; exit(1); } // create socket for incoming connections SOCKET servSock; if(servSock=socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)==INVALID_SOCKET) DieWithError("socket() failed"); // construct local address structure struct sockaddr_in servAddr; memset(&servAddr, 0, sizeof(servAddr)); servAddr.sin_family = AF_INET; servAddr.sin_addr.s_addr = INADDR_ANY; servAddr.sin_port = htons(atoi(argv[1])); // bind to the local address int servAddrLen = sizeof(servAddr); if(bind(servSock, (SOCKADDR*)&servAddr, servAddrLen)==SOCKET_ERROR) DieWithError("bind() failed"); // mark the socket to listen for incoming connections if(listen(servSock, MAXPENDING)<0) DieWithError("listen() failed"); // accept incoming connections int clientSock; struct sockaddr_in clientAddr; char buffer[MAX_LENGTH]; int recvMsgSize; int clientAddrLen = sizeof(clientAddr); for(;;){ // wait for a client to connect if((clientSock=accept(servSock, (sockaddr*)&clientAddr, &clientAddrLen))<0) DieWithError("accept() failed"); // clientSock is connected to a client // BEGIN Handle client cout << "Handling client " << inet_ntoa(clientAddr.sin_addr) << endl; if((recvMsgSize = recv(clientSock, buffer, MAX_LENGTH, 0)) <0) DieWithError("recv() failed"); cout << "Word in the tubes: " << buffer << endl; closesocket(clientSock); // END Handle client } } void DieWithError(char *errorMessage) { fprintf(stderr, "%s: %d\n", errorMessage, WSAGetLastError()); exit(1); }

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