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• Lubuntu 13.10 unable to connect to cups localhost:631

  - by user142139

  I am using Lubuntu 13.10 (recently upgraded) and am trying to print to a network printer (HP photosmart 7960) through my router (US Robotics 5461). My printer is connected to the router via USB cable. Normally, I would use the cups configuration interface to set up the wireless connection to the printer. I was able to use the printer through the router wirelessly, using Ubuntu 12.04. Now, with my recently upgraded Lubuntu 13.10, I am unable to get the Cups config webpage (http://localhost:631) to come up. In Chromium, I get: This web page is not available. In Firefox, I get: Unable to connect. Firefox can't establish a connection to the server at localhost:631. The CUPS config file details are below. I have this website to help with the router connections for Linux: http://www.usr.com/support/5461/5461-files/printer_installation_linux/index.html My printer's address through the router is: http://192.168.2.1:1631/printers/My_Printer Can you tell me how to fix this? Or, what to add to the cups configuration file to make this work? Please help. Thanks psychicnut CUPS CONFIG FILE DETAILS: # Show general information in error_log. LogLevel warn MaxLogSize 0 SystemGroup lpadmin Listen /var/run/cups/cups.sock Listen /var/run/cups/cups.sock Listen 192.168.2.1:1631 Browsing Off BrowseLocalProtocols dnssd DefaultAuthType Basic WebInterface Yes <Location /> Order allow,deny </Location> <Location /admin> Order allow,deny </Location> <Location /admin/conf> AuthType Default Require user @SYSTEM Order allow,deny </Location> <Policy default> JobPrivateAccess default JobPrivateValues default SubscriptionPrivateAccess default SubscriptionPrivateValues default <Limit Create-Job Print-Job Print-URI Validate-Job> Order deny,allow </Limit> <Limit Send-Document Send-URI Hold-Job Release-Job Restart-Job Purge-Jobs Set-Job-Attributes Create-Job-Subscription Renew-Subscription Cancel-Subscription Get-Notifications Reprocess-Job Cancel-Current-Job Suspend-Current-Job Resume-Job Cancel-My-Jobs Close-Job CUPS-Move-Job CUPS-Get-Document> Require user @OWNER @SYSTEM Order deny,allow </Limit> <Limit CUPS-Add-Modify-Printer CUPS-Delete-Printer CUPS-Add-Modify-Class CUPS-Delete-Class CUPS-Set-Default CUPS-Get-Devices> AuthType Default Require user @SYSTEM Order deny,allow </Limit> <Limit Pause-Printer Resume-Printer Enable-Printer Disable-Printer Pause-Printer-After-Current-Job Hold-New-Jobs Release-Held-New-Jobs Deactivate-Printer Activate-Printer Restart-Printer Shutdown-Printer Startup-Printer Promote-Job Schedule-Job-After Cancel-Jobs CUPS-Accept-Jobs CUPS-Reject-Jobs> AuthType Default Require user @SYSTEM Order deny,allow </Limit> <Limit Cancel-Job CUPS-Authenticate-Job> Require user @OWNER @SYSTEM Order deny,allow </Limit> <Limit All> Order deny,allow </Limit> </Policy> <Policy authenticated> JobPrivateAccess default JobPrivateValues default SubscriptionPrivateAccess default SubscriptionPrivateValues default <Limit Create-Job Print-Job Print-URI Validate-Job> AuthType Default Order deny,allow </Limit> <Limit Send-Document Send-URI Hold-Job Release-Job Restart-Job Purge-Jobs Set-Job-Attributes Create-Job-Subscription Renew-Subscription Cancel-Subscription Get-Notifications Reprocess-Job Cancel-Current-Job Suspend-Current-Job Resume-Job Cancel-My-Jobs Close-Job CUPS-Move-Job CUPS-Get-Document> AuthType Default Require user @OWNER @SYSTEM Order deny,allow </Limit> <Limit CUPS-Add-Modify-Printer CUPS-Delete-Printer CUPS-Add-Modify-Class CUPS-Delete-Class CUPS-Set-Default> AuthType Default Require user @SYSTEM Order deny,allow </Limit> <Limit Pause-Printer Resume-Printer Enable-Printer Disable-Printer Pause-Printer-After-Current-Job Hold-New-Jobs Release-Held-New-Jobs Deactivate-Printer Activate-Printer Restart-Printer Shutdown-Printer Startup-Printer Promote-Job Schedule-Job-After Cancel-Jobs CUPS-Accept-Jobs CUPS-Reject-Jobs> AuthType Default Require user @SYSTEM Order deny,allow </Limit> <Limit Cancel-Job CUPS-Authenticate-Job> AuthType Default Require user @OWNER @SYSTEM Order deny,allow </Limit> <Limit All> Order deny,allow </Limit> </Policy> JobPrivateAccess default JobPrivateValues default SubscriptionPrivateAccess default SubscriptionPrivateValues default

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• C# 4.0: Named And Optional Arguments

  - by Paulo Morgado

  As part of the co-evolution effort of C# and Visual Basic, C# 4.0 introduces Named and Optional Arguments. First of all, let’s clarify what are arguments and parameters: Method definition parameters are the input variables of the method. Method call arguments are the values provided to the method parameters. In fact, the C# Language Specification states the following on §7.5: The argument list (§7.5.1) of a function member invocation provides actual values or variable references for the parameters of the function member. Given the above definitions, we can state that: Parameters have always been named and still are. Parameters have never been optional and still aren’t. Named Arguments Until now, the way the C# compiler matched method call definition arguments with method parameters was by position. The first argument provides the value for the first parameter, the second argument provides the value for the second parameter, and so on and so on, regardless of the name of the parameters. If a parameter was missing a corresponding argument to provide its value, the compiler would emit a compilation error. For this call: Greeting("Mr.", "Morgado", 42); this method: public void Greeting(string title, string name, int age) will receive as parameters: title: “Mr.” name: “Morgado” age: 42 What this new feature allows is to use the names of the parameters to identify the corresponding arguments in the form: name:value Not all arguments in the argument list must be named. However, all named arguments must be at the end of the argument list. The matching between arguments (and the evaluation of its value) and parameters will be done first by name for the named arguments and than by position for the unnamed arguments. This means that, for this method definition: public static void Method(int first, int second, int third) this call declaration: int i = 0; Method(i, third: i++, second: ++i); will have this code generated by the compiler: int i = 0; int CS$0$0000 = i++; int CS$0$0001 = ++i; Method(i, CS$0$0001, CS$0$0000); which will give the method the following parameter values: first: 2 second: 2 third: 0 Notice the variable names. Although invalid being invalid C# identifiers, they are valid .NET identifiers and thus avoiding collision between user written and compiler generated code. Besides allowing to re-order of the argument list, this feature is very useful for auto-documenting the code, for example, when the argument list is very long or not clear, from the call site, what the arguments are. Optional Arguments Parameters can now have default values: public static void Method(int first, int second = 2, int third = 3) Parameters with default values must be the last in the parameter list and its value is used as the value of the parameter if the corresponding argument is missing from the method call declaration. For this call declaration: int i = 0; Method(i, third: ++i); will have this code generated by the compiler: int i = 0; int CS$0$0000 = ++i; Method(i, 2, CS$0$0000); which will give the method the following parameter values: first: 1 second: 2 third: 1 Because, when method parameters have default values, arguments can be omitted from the call declaration, this might seem like method overloading or a good replacement for it, but it isn’t. Although methods like this: public static StreamReader OpenTextFile( string path, Encoding encoding = null, bool detectEncoding = true, int bufferSize = 1024) allow to have its calls written like this: OpenTextFile("foo.txt", Encoding.UTF8); OpenTextFile("foo.txt", Encoding.UTF8, bufferSize: 4096); OpenTextFile( bufferSize: 4096, path: "foo.txt", detectEncoding: false); The complier handles default values like constant fields taking the value and useing it instead of a reference to the value. So, like with constant fields, methods with parameters with default values are exposed publicly (and remember that internal members might be publicly accessible – InternalsVisibleToAttribute). If such methods are publicly accessible and used by another assembly, those values will be hard coded in the calling code and, if the called assembly has its default values changed, they won’t be assumed by already compiled code. At the first glance, I though that using optional arguments for “bad” written code was great, but the ability to write code like that was just pure evil. But than I realized that, since I use private constant fields, it’s OK to use default parameter values on privately accessed methods.

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• The Interaction between Three-Tier Client/Server Model and Three-Tier Application Architecture Model

  The three-tier client/server model is a network architectural approach currently used in modern networking. This approach divides a network in to three distinct components. Three-Tier Client/Server Model Components Client Component Server Component Database Component The Client Component of the network typically represents any device on the network. A basic example of this would be computer or another network/web enabled devices that are connected to a network. Network clients request resources on the network, and are usually equipped with a user interface for the presentation of the data returned from the Server Component. This process is done through the use of various software clients, and example of this can be seen through the use of a web browser client. The web browser request information from the Server Component located on the network and then renders the results for the user to process. The Server Components of the network return data based on specific client request back to the requesting client.  Server Components also inherit the attributes of a Client Component in that they are a device on the network and that they can also request information from other Server Components. However what differentiates a Client Component from a Server Component is that a Server Component response to requests from devices on the network. An example of a Server Component can be seen in a web server. A web server listens for new requests and then interprets the request, processes the web pages, and then returns the processed data back to the web browser client so that it may render the data for the user to interpret. The Database Component of the network returns unprocessed data from databases or other resources. This component also inherits attributes from the Server Component in that it is a device on a network, it can request information from other server components and database components, and it also listens for new requests so that it can return data when needed. The three-tier client/server model is very similar to the three-tier application architecture model, and in fact the layers can be mapped to one another. Three-Tier Application Architecture Model Presentation Layer/Logic Business Layer/Logic Data Layer/Logic The Presentation Layer including its underlying logic is very similar to the Client Component of the three-tiered model. The Presentation Layer focuses on interpreting the data returned by the Business Layer as well as presents the data back to the user.  Both the Presentation Layer and the Client Component focus primarily on the user and their experience. This allows for segments of the Business Layer to be distributable and interchangeable because the Presentation Layer is not directly integrated in with Business Layer. The Presentation Layer does not care where the data comes from as long as it is in the proper format. This allows for the Presentation Layer and Business Layer to be stored on one or more different servers so that it can provide a higher availability to clients requesting data. A good example of this is a web site that uses load balancing. When a web site decides to take on the task of load balancing they must obtain a network device that sits in front of a one or machines in order to distribute the request across multiple servers. When a user comes in through the load balanced device they are redirected to a specific server based on a few factors. Common Load Balancing Factors Current Server Availability Current Server Response Time Current Server Priority The Business Layer and corresponding logic are business rules applied to data prior to it being sent to the Presentation Layer. These rules are used to manipulate the data coming from the Data Access Layer, in addition to validating any data prior to being stored in the Data Access Layer. A good example of this would be when a user is trying to create multiple accounts under one email address. The Business Layer logic can prevent duplicate accounts by enforcing a unique email for every new account before the data is even stored in the Data Access Layer. The Server Component can be directly tied to this layer in that the server typically stores and process the Business Layer before it is returned to the end-user via the Presentation Layer. In addition the Server Component can also run automated process through the Business Layer on the data in the Data Access Layer so that additional business analysis can be derived from the data that has been already collected. The Data Layer and its logic are responsible for storing information so that it can be easily retrieved. Typical in most modern applications data is stored in a database management system however data can also be in the form of files stored on a file server. In addition a database can take on one of several forms. Common Database Formats XML File Pipe Delimited File Tab Delimited File Comma Delimited File (CSV) Plain Text File Microsoft Access Microsoft SQL Server MySql Oracle Sybase The Database component of the Networking model can be directly tied to the Data Layer because this is where the Data Layer obtains the data to return back the Business Layer. The Database Component basically allows for a place on the network to store data for future use. This enables applications to save data when they can and then quickly recall the saved data as needed so that the application does not have to worry about storing the data in memory. This prevents overhead that could be created when an application must retain all data in memory. As you can see the Three-Tier Client/Server Networking Model and the Three-Tiered Application Architecture Model rely very heavily on one another to function especially if different aspects of an application are distributed across an entire network. The use of various servers and database servers are wonderful when an application has a need to distribute work across the network. Network Components and Application Layers Interaction Database components will store all data needed for the Data Access Layer to manipulate and return to the Business Layer Server Component executes the Business Layer that manipulates data so that it can be returned to the Presentation Layer Client Component hosts the Presentation Layer that  interprets the data and present it to the user

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• SQL SERVER – Beginning of SQL Server Architecture – Terminology – Guest Post

  - by pinaldave

  SQL Server Architecture is a very deep subject. Covering it in a single post is an almost impossible task. However, this subject is very popular topic among beginners and advanced users.  I have requested my friend Anil Kumar who is expert in SQL Domain to help me write  a simple post about Beginning SQL Server Architecture. As stated earlier this subject is very deep subject and in this first article series he has covered basic terminologies. In future article he will explore the subject further down. Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. In this Article we will discuss about MS SQL Server architecture. The major components of SQL Server are: Relational Engine Storage Engine SQL OS Now we will discuss and understand each one of them. 1) Relational Engine: Also called as the query processor, Relational Engine includes the components of SQL Server that determine what your query exactly needs to do and the best way to do it. It manages the execution of queries as it requests data from the storage engine and processes the results returned. Different Tasks of Relational Engine: Query Processing Memory Management Thread and Task Management Buffer Management Distributed Query Processing 2) Storage Engine: Storage Engine is responsible for storage and retrieval of the data on to the storage system (Disk, SAN etc.). to understand more, let’s focus on the following diagram. When we talk about any database in SQL server, there are 2 types of files that are created at the disk level – Data file and Log file. Data file physically stores the data in data pages. Log files that are also known as write ahead logs, are used for storing transactions performed on the database. Let’s understand data file and log file in more details: Data File: Data File stores data in the form of Data Page (8KB) and these data pages are logically organized in extents. Extents: Extents are logical units in the database. They are a combination of 8 data pages i.e. 64 KB forms an extent. Extents can be of two types, Mixed and Uniform. Mixed extents hold different types of pages like index, System, Object data etc. On the other hand, Uniform extents are dedicated to only one type. Pages: As we should know what type of data pages can be stored in SQL Server, below mentioned are some of them: Data Page: It holds the data entered by the user but not the data which is of type text, ntext, nvarchar(max), varchar(max), varbinary(max), image and xml data. Index: It stores the index entries. Text/Image: It stores LOB ( Large Object data) like text, ntext, varchar(max), nvarchar(max),  varbinary(max), image and xml data. GAM & SGAM (Global Allocation Map & Shared Global Allocation Map): They are used for saving information related to the allocation of extents. PFS (Page Free Space): Information related to page allocation and unused space available on pages. IAM (Index Allocation Map): Information pertaining to extents that are used by a table or index per allocation unit. BCM (Bulk Changed Map): Keeps information about the extents changed in a Bulk Operation. DCM (Differential Change Map): This is the information of extents that have modified since the last BACKUP DATABASE statement as per allocation unit. Log File: It also known as write ahead log. It stores modification to the database (DML and DDL). Sufficient information is logged to be able to: Roll back transactions if requested Recover the database in case of failure Write Ahead Logging is used to create log entries Transaction logs are written in chronological order in a circular way Truncation policy for logs is based on the recovery model SQL OS: This lies between the host machine (Windows OS) and SQL Server. All the activities performed on database engine are taken care of by SQL OS. It is a highly configurable operating system with powerful API (application programming interface), enabling automatic locality and advanced parallelism. SQL OS provides various operating system services, such as memory management deals with buffer pool, log buffer and deadlock detection using the blocking and locking structure. Other services include exception handling, hosting for external components like Common Language Runtime, CLR etc. I guess this brief article gives you an idea about the various terminologies used related to SQL Server Architecture. In future articles we will explore them further. Guest Author  The author of the article is Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Security, SQL Server, SQL Tips and Tricks, SQL Training, T SQL, Technology

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• RK4 Bouncing a Ball

  - by Jonathan Dickinson

  I am trying to wrap my head around RK4. I decided to do the most basic 'ball with gravity that bounces' simulation. I have implemented the following integrator given Glenn Fiedler's tutorial: /// <summary> /// Represents physics state. /// </summary> public struct State { // Also used internally as derivative. // S: Position // D: Velocity. /// <summary> /// Gets or sets the Position. /// </summary> public Vector2 X; // S: Position // D: Acceleration. /// <summary> /// Gets or sets the Velocity. /// </summary> public Vector2 V; } /// <summary> /// Calculates the force given the specified state. /// </summary> /// <param name="state">The state.</param> /// <param name="t">The time.</param> /// <param name="acceleration">The value that should be updated with the acceleration.</param> public delegate void EulerIntegrator(ref State state, float t, ref Vector2 acceleration); /// <summary> /// Represents the RK4 Integrator. /// </summary> public static class RK4 { private const float OneSixth = 1.0f / 6.0f; private static void Evaluate(EulerIntegrator integrator, ref State initial, float t, float dt, ref State derivative, ref State output) { var state = new State(); // These are a premature optimization. I like premature optimization. // So let's not concentrate on that. state.X.X = initial.X.X + derivative.X.X * dt; state.X.Y = initial.X.Y + derivative.X.Y * dt; state.V.X = initial.V.X + derivative.V.X * dt; state.V.Y = initial.V.Y + derivative.V.Y * dt; output = new State(); output.X.X = state.V.X; output.X.Y = state.V.Y; integrator(ref state, t + dt, ref output.V); } /// <summary> /// Performs RK4 integration over the specified state. /// </summary> /// <param name="eulerIntegrator">The euler integrator.</param> /// <param name="state">The state.</param> /// <param name="t">The t.</param> /// <param name="dt">The dt.</param> public static void Integrate(EulerIntegrator eulerIntegrator, ref State state, float t, float dt) { var a = new State(); var b = new State(); var c = new State(); var d = new State(); Evaluate(eulerIntegrator, ref state, t, 0.0f, ref a, ref a); Evaluate(eulerIntegrator, ref state, t + dt * 0.5f, dt * 0.5f, ref a, ref b); Evaluate(eulerIntegrator, ref state, t + dt * 0.5f, dt * 0.5f, ref b, ref c); Evaluate(eulerIntegrator, ref state, t + dt, dt, ref c, ref d); a.X.X = OneSixth * (a.X.X + 2.0f * (b.X.X + c.X.X) + d.X.X); a.X.Y = OneSixth * (a.X.Y + 2.0f * (b.X.Y + c.X.Y) + d.X.Y); a.V.X = OneSixth * (a.V.X + 2.0f * (b.V.X + c.V.X) + d.V.X); a.V.Y = OneSixth * (a.V.Y + 2.0f * (b.V.Y + c.V.Y) + d.V.Y); state.X.X = state.X.X + a.X.X * dt; state.X.Y = state.X.Y + a.X.Y * dt; state.V.X = state.V.X + a.V.X * dt; state.V.Y = state.V.Y + a.V.Y * dt; } } After reading over the tutorial I noticed a few things that just seemed 'out' to me. Notably how the entire simulation revolves around t at 0 and state at 0 - considering that we are working out a curve over the duration it seems logical that RK4 wouldn't be able to handle this simple scenario. Never-the-less I forged on and wrote a very simple Euler integrator: static void Integrator(ref State state, float t, ref Vector2 acceleration) { if (state.X.Y > 100 && state.V.Y > 0) { // Bounce vertically. acceleration.Y = -state.V.Y * t; } else { acceleration.Y = 9.8f; } } I then ran the code against a simple fixed-time step loop and this is what I got: 0.05 0.20 0.44 0.78 1.23 1.76 ... 74.53 78.40 82.37 86.44 90.60 94.86 99.23 103.05 105.45 106.94 107.86 108.42 108.76 108.96 109.08 109.15 109.19 109.21 109.23 109.23 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 ... As I said, I was expecting it to break - however I am unsure of how to fix it. I am currently looking into keeping the previous state and time, and working from that - although at the same time I assume that will defeat the purpose of RK4. How would I get this simulation to print the expected results?

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• Play Your Favorite DOS Games in XP, Vista, and Windows 7

  - by Matthew Guay

  Want to take a trip down memory lane with old school DOS games?  D-Fend Reloaded makes it easy for you to play your favorite DOS games directly on XP, Vista, and Windows 7. D-Fend Reloaded is a great frontend for DOSBox, the popular DOS emulator.  It lets you install and run many DOS games and applications directly from its interface without ever touching a DOS prompt.  It works great on XP, Vista, and Windows 7 32 & 64-bit versions.   Getting Started Download D-Fend Reloaded (link below), and install with the default settings.  You don’t need to install DOSBox, as D-Fend Reloaded will automatically install all the components you need to run DOS games on Windows. D-Fend Reloaded can also be installed as a portable application, so you can run it from a flash drive on any Windows computer by selecting User defined installation. Then select Portable mode installation. Once D-Fend Reloaded is installed, you can go ahead and open the program. Then simply click “Accept all settings” to apply the default settings.   D-Fend is now ready to run all of your favorite DOS games. Installing DOS Games and Applications: To install a DOS game or application, simply drag-and-drop a zip file of the app into D-Fend Reloaded’s window.  D-Fend Reloaded will automatically extract the program… Then will ask you to name the application and choose where to store it — by default it uses the name of the DOS app. Now you’ll see a new entry for the app you just installed.  Simply double-click to run it.   D-Fend will remind you that you can switch out of fullscreen mode by pressing Alt+Enter, and can also close the DOS application by pressing Ctrl+F9.  Press Ok to run the program. Here we’re running Ms. PacPC, a remake of the classic game Ms. Pac-Man, in full-screen mode.  All features work automatically, including sound, and you never have to setup anything from DOS command line — it just works. Here it’s in windowed mode running on Windows 7. Please note that your color scheme may change to Windows Basic while running DOS applications. You can run DOS application just as easily.  Here’s Word 5.5 running in in DOSBox through D-Fend Reloaded… Game Packs: Want to quickly install many old DOS freeware and trial games?  D-Fend Reloaded offers several game packs that let you install dozens of DOS games with only four clicks…just download and run the game pack installer of your choice (link below). Now you’ve got a selection of DOS games to choose from. Here’s a group of poor lemmings walking around … in Windows 7. Conclusion D-Fend Reloaded gives you a great way to run your favorite DOS games and applications directly from XP, Vista, and Windows 7.  Give it a try, and relive your DOS days from the comfort of your Windows desktop. What were some of your favorite DOS games and applications? Leave a comment and let us know. Links Download D-Fend Reloaded Download DOS game packs for D-Fend Reloaded Download Ms. Pac-PC Similar Articles Productive Geek Tips Friday Fun: Get Your Mario OnFriday Fun: Go Retro with PacmanThursday’s Pre-Holiday Lazy Links RoundupFriday Fun: Five More Time Wasting Online GamesFriday Fun: Holiday Themed Games TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional The Growth of Citibank Quickly Switch between Tabs in IE Windows Media Player 12: Tweak Video & Sound with Playback Enhancements Own a cell phone, or does a cell phone own you? Make your Joomla & Drupal Sites Mobile with OSMOBI Integrate Twitter and Delicious and Make Life Easier

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• Nerdstock 2012: A photo review of Microsoft TechEd North America 2012

  - by The Un-T Guy

  Not only could I not fathom that I would ever be attending a tech event of the magnitude of TechEd, neither could any of my co-workers.  As the least technical person in the history of Information Technology ever, I felt as though I were walking into the belly of the beast, fearing I’d not be allowed out until I could write SSIS packages, program in Visual Basic, or at least arm wrestle a DBA.  Most of my fears were unrealized.   But I made it.  I was here.  I even got to wear the Mark of the Geek neck package with schedule, eyeglass cleaners, name badge (company name obfuscated so they don’t fire me), and a pen.  The name  badge was seemingly the key element, as every vendor in the place wanted to scan it to capture name, email address, and numbers to show their bosses back home.  It also let me eat the food and drink the coffee so that’s a fair trade.   A recurring theme throughout the presentations and vendor demos was “the Cloud” and BYOD (bring your own device).  The below was a common site throughout the week, as attendees from all over the world brought their own devices and were able to (seemingly) seamlessly connect to the Worldwide Innerwebs.  Apparently proof that Microsoft and the event organizers were practicing what they were preaching.   “Cavernous” is one way to describe the downstairs facility itself.  “Freaking cavernous” might be more accurate.  Work sessions were held in classrooms on the second and third floors but the real action was happening downstairs.  Microsoft bookstore, blogger hub (shoutout to Geekswithblogs.net), The Wall (sans Pink Floyd, sadly), couches, recharging stations…   …a game zone with pool and air hockey tables, pinball machines, foosball…   …vintage video games…           …and a even giant chess board.  Looked like this guy was opening with the Kaspersky parry.   The blend of technology and fantasy even went so far as to bring childhood favorites to life.  Assuming, of course, your childhood was pre-video games (like mine) and you were stuck with electric football and Rock ‘em Sock ‘em robots:   And, lest the “combatants” become unruly or – God forbid – afternoon snacks were late, Orange County’s finest was on the scene to keep the peace.  On a high-tech mode of transport, of course.   She wasn’t the only one to think this was a swell way to transition from one concourse to the next.  Given the level of support provided by the entire Orange County Convention Center staff, I knew they had to have some secret.   Here’s one entrance to the vendor zone/”Technical Learning Center.”  Couldn’t help but think of them as the remora attached to the Whale Shark that is Microsoft…   …or perhaps planets orbiting the sun. Microsoft is just that huge and it seemed like every vendor in the industry looks forward to partnering with the tech behemoth.   Aside from the free stuff from the vendors, probably the most popular place in the house was the dining area.  Amazing spreads every day, multiple times a day.  While no attendance numbers were available at press time, literally thousands of attendees were fed, and fed well, every day.  And lest you think my post from earlier in the week exaggerated about the backpacks…   …or that I’m exaggerating about the lunch crowds.  This represents only about between 25-30% of the lunch crowd – it was all my camera could capture at once.  No one went away hungry.   The only thing missing was a a vat of Red Bull but apparently organizers went old school, with probably 100 urns of the original energy drink – coffee – all around the venue.   Of course, following lunch and afternoon sessions, some preferred the even older school method of re-energizing.  There were rumors that Microsoft was serving graham crackers and milk in this area.  But they were only rumors.   Cannot overstate the wonderful service provided by the Orange County Convention Center staff.  Coffee, soft drinks, juice, and water were available always.  Buffet meals were delicious with a wide range of healthy options available, in addition to hundreds (at least) special meal requests supported every day.  Ever tried to keep up with an estimated 9,000 hungry and thirsty IT-ers?  These folks did.  Kudos to all of the staff and many thanks!   And while I occasionally poke fun at the Whale Shark, if nothing else this experience convinced me of one thing:  Microsoft knows how to put on a professional event.  Hundreds of informative, professionally delivered sessions, covering a wide range of topics set at varying levels of expertise (some that even I was able to follow), social activities, vendor partnerships…they brought everything you could ask for to inform, educate, and inspire an entire IT industry.   So as I depart the belly of the beast, I can both take pride in the fact that I survived the week and marvel at the brilliance surrounding me.  The IT industry – or at least the segment associated with Microsoft – is in good, professional hands.  And what won’t fit in their hands can be toted in the Microsoft provided backpacks.  Win-win.   Until New Orleans…

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• JPA - insert and retrieve clob and blob types

  - by pachunoori.vinay.kumar(at)oracle.com

  This article describes about the JPA feature for handling clob and blob data types.You will learn the following in this article. @Lob annotation Client code to insert and retrieve the clob/blob types End to End ADFaces application to retrieve the image from database table and display it in web page. Use Case Description Persisting and reading the image from database using JPA clob/blob type. @Lob annotation By default, TopLink JPA assumes that all persistent data can be represented as typical database data types. Use the @Lob annotation with a basic mapping to specify that a persistent property or field should be persisted as a large object to a database-supported large object type. A Lob may be either a binary or character type. TopLink JPA infers the Lob type from the type of the persistent field or property. For string and character-based types, the default is Clob. In all other cases, the default is Blob. Example Below code shows how to use this annotation to specify that persistent field picture should be persisted as a Blob. public class Person implements Serializable {    @Id    @Column(nullable = false, length = 20)    private String name;    @Column(nullable = false)    @Lob    private byte[] picture;    @Column(nullable = false, length = 20) } Client code to insert and retrieve the clob/blob types Reading a image file and inserting to Database table Below client code will read the image from a file and persist to Person table in database.                       Person p=new Person();                      p.setName("Tom");                      p.setSex("male");                      p.setPicture(writtingImage("Image location"));// - c:\images\test.jpg                       sessionEJB.persistPerson(p); //Retrieving the image from Database table and writing to a file                       List<Person> plist=sessionEJB.getPersonFindAll();//                      Person person=(Person)plist.get(0);//get a person object                      retrieveImage(person.getPicture());   //get picture retrieved from Table //Private method to create byte[] from image file  private static byte[] writtingImage(String fileLocation) {      System.out.println("file lication is"+fileLocation);     IOManager manager=new IOManager();        try {           return manager.getBytesFromFile(fileLocation);                    } catch (IOException e) {        }        return null;    } //Private method to read byte[] from database and write to a image file    private static void retrieveImage(byte[] b) {    IOManager manager=new IOManager();        try {            manager.putBytesInFile("c:\\webtest.jpg",b);        } catch (IOException e) {        }    } End to End ADFaces application to retrieve the image from database table and display it in web page. Please find the application in this link. Following are the j2ee components used in the sample application. ADFFaces(jspx page) HttpServlet Class - Will make a call to EJB and retrieve the person object from person table.Read the byte[] and write to response using Outputstream. SessionEJBBean - This is a session facade to make a local call to JPA entities JPA Entity(Person.java) - Person java class with setter and getter method annotated with @Lob representing the clob/blob types for picture field.

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• Troubleshooting High-CPU Utilization for SQL Server

  - by Susantha Bathige

  The objective of this FAQ is to outline the basic steps in troubleshooting high CPU utilization on  a server hosting a SQL Server instance. The first and the most common step if you suspect high CPU utilization (or are alerted for it) is to login to the physical server and check the Windows Task Manager. The Performance tab will show the high utilization as shown below: Next, we need to determine which process is responsible for the high CPU consumption. The Processes tab of the Task Manager will show this information: Note that to see all processes you should select Show processes from all user. In this case, SQL Server (sqlserver.exe) is consuming 99% of the CPU (a normal benchmark for max CPU utilization is about 50-60%). Next we examine the scheduler data. Scheduler is a component of SQLOS which evenly distributes load amongst CPUs. The query below returns the important columns for CPU troubleshooting. Note – if your server is under severe stress and you are unable to login to SSMS, you can use another machine’s SSMS to login to the server through DAC – Dedicated Administrator Connection (see http://msdn.microsoft.com/en-us/library/ms189595.aspx for details on using DAC) SELECT scheduler_id ,cpu_id ,status ,runnable_tasks_count ,active_workers_count ,load_factor ,yield_count FROM sys.dm_os_schedulers WHERE scheduler_id See below for the BOL definitions for the above columns. scheduler_id – ID of the scheduler. All schedulers that are used to run regular queries have ID numbers less than 1048576. Those schedulers that have IDs greater than or equal to 1048576 are used internally by SQL Server, such as the dedicated administrator connection scheduler. cpu_id – ID of the CPU with which this scheduler is associated. status – Indicates the status of the scheduler. runnable_tasks_count – Number of workers, with tasks assigned to them that are waiting to be scheduled on the runnable queue. active_workers_count – Number of workers that are active. An active worker is never preemptive, must have an associated task, and is either running, runnable, or suspended. current_tasks_count - Number of current tasks that are associated with this scheduler. load_factor – Internal value that indicates the perceived load on this scheduler. yield_count – Internal value that is used to indicate progress on this scheduler.                                                                 Now to interpret the above data. There are four schedulers and each assigned to a different CPU. All the CPUs are ready to accept user queries as they all are ONLINE. There are 294 active tasks in the output as per the current_tasks_count column. This count indicates how many activities currently associated with the schedulers. When a  task is complete, this number is decremented. The 294 is quite a high figure and indicates all four schedulers are extremely busy. When a task is enqueued, the load_factor  value is incremented. This value is used to determine whether a new task should be put on this scheduler or another scheduler. The new task will be allocated to less loaded scheduler by SQLOS. The very high value of this column indicates all the schedulers have a high load. There are 268 runnable tasks which mean all these tasks are assigned a worker and waiting to be scheduled on the runnable queue.   The next step is  to identify which queries are demanding a lot of CPU time. The below query is useful for this purpose (note, in its current form,  it only shows the top 10 records). SELECT TOP 10 st.text  ,st.dbid  ,st.objectid  ,qs.total_worker_time  ,qs.last_worker_time  ,qp.query_plan FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp ORDER BY qs.total_worker_time DESC This query as total_worker_time as the measure of CPU load and is in descending order of the  total_worker_time to show the most expensive queries and their plans at the top:      Note the BOL definitions for the important columns: total_worker_time - Total amount of CPU time, in microseconds, that was consumed by executions of this plan since it was compiled. last_worker_time - CPU time, in microseconds, that was consumed the last time the plan was executed.   I re-ran the same query again after few seconds and was returned the below output. After few seconds the SP dbo.TestProc1 is shown in fourth place and once again the last_worker_time is the highest. This means the procedure TestProc1 consumes a CPU time continuously each time it executes.      In this case, the primary cause for high CPU utilization was a stored procedure. You can view the execution plan by clicking on query_plan column to investigate why this is causing a high CPU load. I have used SQL Server 2008 (SP1) to test all the queries used in this article.

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• Inserting and Deleting Sub Rows in GridView

  - by Vincent Maverick Durano

  A user in the forums (http://forums.asp.net) is asking how to insert  sub rows in GridView and also add delete functionality for the inserted sub rows. In this post I'm going to demonstrate how to this in ASP.NET WebForms.  The basic idea to achieve this is we just need to insert row data in the DataSource that is being used in GridView since the GridView rows will be generated based on the DataSource data. To make it more clear then let's build up a sample application. To start fire up Visual Studio and create a WebSite or Web Application project and then add a new WebForm. In the WebForm ASPX page add this GridView markup below:   1: <asp:gridview ID="GridView1" runat="server" AutoGenerateColumns="false" onrowdatabound="GridView1_RowDataBound"> 2: <Columns> 3: <asp:BoundField DataField="RowNumber" HeaderText="Row Number" /> 4: <asp:TemplateField HeaderText="Header 1"> 5: <ItemTemplate> 6: <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> 7: </ItemTemplate> 8: </asp:TemplateField> 9: <asp:TemplateField HeaderText="Header 2"> 10: <ItemTemplate> 11: <asp:TextBox ID="TextBox2" runat="server"></asp:TextBox> 12: </ItemTemplate> 13: </asp:TemplateField> 14: <asp:TemplateField HeaderText="Header 3"> 15: <ItemTemplate> 16: <asp:TextBox ID="TextBox3" runat="server"></asp:TextBox> 17: </ItemTemplate> 18: </asp:TemplateField> 19: <asp:TemplateField HeaderText="Action"> 20: <ItemTemplate> 21: <asp:LinkButton ID="LinkButton1" runat="server" onclick="LinkButton1_Click" Text="Insert"></asp:LinkButton> 22: </ItemTemplate> 23: </asp:TemplateField> 24: </Columns> 25: </asp:gridview>   Then at the code behind source of ASPX page you can add this codes below:   1: private DataTable FillData() { 2:   3: DataTable dt = new DataTable(); 4: DataRow dr = null; 5:   6: //Create DataTable columns 7: dt.Columns.Add(new DataColumn("RowNumber", typeof(string))); 8:   9: //Create Row for each columns 10: dr = dt.NewRow(); 11: dr["RowNumber"] = 1; 12: dt.Rows.Add(dr); 13:   14: dr = dt.NewRow(); 15: dr["RowNumber"] = 2; 16: dt.Rows.Add(dr); 17:   18: dr = dt.NewRow(); 19: dr["RowNumber"] = 3; 20: dt.Rows.Add(dr); 21:   22: dr = dt.NewRow(); 23: dr["RowNumber"] = 4; 24: dt.Rows.Add(dr); 25:   26: dr = dt.NewRow(); 27: dr["RowNumber"] = 5; 28: dt.Rows.Add(dr); 29:   30: //Store the DataTable in ViewState for future reference 31: ViewState["CurrentTable"] = dt; 32:   33: return dt; 34:   35: } 36:   37: private void BindGridView(DataTable dtSource) { 38: GridView1.DataSource = dtSource; 39: GridView1.DataBind(); 40: } 41:   42: private DataRow InsertRow(DataTable dtSource, string value) { 43: DataRow dr = dtSource.NewRow(); 44: dr["RowNumber"] = value; 45: return dr; 46: } 47: //private DataRow DeleteRow(DataTable dtSource, 48:   49: protected void Page_Load(object sender, EventArgs e) { 50: if (!IsPostBack) { 51: BindGridView(FillData()); 52: } 53: } 54:   55: protected void LinkButton1_Click(object sender, EventArgs e) { 56: LinkButton lb = (LinkButton)sender; 57: GridViewRow row = (GridViewRow)lb.NamingContainer; 58: DataTable dtCurrentData = (DataTable)ViewState["CurrentTable"]; 59: if (lb.Text == "Insert") { 60: //Insert new row below the selected row 61: dtCurrentData.Rows.InsertAt(InsertRow(dtCurrentData, row.Cells[0].Text + "-sub"), row.RowIndex + 1); 62:   63: } 64: else { 65: //Delete selected sub row 66: dtCurrentData.Rows.RemoveAt(row.RowIndex); 67: } 68:   69: BindGridView(dtCurrentData); 70: ViewState["CurrentTable"] = dtCurrentData; 71: } 72:   73: protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e) { 74: if (e.Row.RowType == DataControlRowType.DataRow) { 75: if (e.Row.Cells[0].Text.Contains("-sub")) { 76: ((LinkButton)e.Row.FindControl("LinkButton1")).Text = "Delete"; 77: } 78: } 79: }   As you can see the code above is pretty straight forward and self explainatory but just to give you a short explaination the code above is composed of three (3) private methods which are the FillData(), BindGridView and InsertRow(). The FillData() method is a method that returns a DataTable and basically creates a dummy data in the DataTable to be used as the GridView DataSource. You can replace the code in that method if you want to use actual data from database but for the purpose of this example I just fill the DataTable with a dummy data on it. The BindGridVew is a method that handles the actual binding of GridVew. The InsertRow() is a method that returns a DataRow. This method handles the insertion of the sub row. Now in the LinkButton OnClick event, we casted the sender to a LinkButton to determine the specific object that fires up the event and get the row values. We then reference the Data from ViewState to get the current data that is being used in the GridView. If the LinkButton text is "Insert" then we will insert new row to the DataSource ( in this case the DataTable) based on the rowIndex if not then Delete the sub row that was added. Here are some screen shots of the output below: On initial load:   After inserting a sub row:   That's it! I hope someone find this post useful!   Technorati Tags: ASP.NET,C#,GridView

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• Record and Play your WebLogic Console Tasks Like a DVR

  - by james.bayer

  Automation using WebLogic Scripting Tool Today on the Oracle internal mailing list for WebLogic Server questions someone asked how to automate the configuration of the thread model for WebLogic Server and they were having trouble with the jython scripting syntax.  I’ve previously written about this feature called Work Managers and the associated constraints.  However, I did not show how to automate the process of configuring this without the console using WebLogic Scripting Tool – the jython scripting automation environment abbreviated as WLST.  I’ve written some very basic introductions to WLST before and there is also an Oracle By Example on the subject, but this is a bit more advanced.  Fear not because there is a really easy-to-use feature of the WLS console that lets you “Record” user actions just like a DVR.  Using these recordings of the web-based console, you can easily create a script even if you are unfamiliar with the WLST syntax and API.  I’m a big fan of both DVR’s and automation as can be evidenced with this old Halloween picture taken during simpler times.  Obviously the Cast Away and The Big Labowski references show some age.  I was a big Tivo fan-boy back in the day and I still think it’s the best DVR. I strongly believe that WebLogic Scripting Tool (WLST) is an absolutely essential tool for automating administration tasks in anything beyond a development environment.  Even in development environments you can make a case that it makes sense to start the automation for environments downstream.  I promise you that once you start using it for any tasks that you do even semi-regularly, you won’t go back to clicking through the console.  It’s simply so much more efficient and less error-prone to run a script. Let’s say you need to create a Work Manager and MaxThreadsConstraint – the easy way to do it is configure it in the WLS console first while capturing the commands with a recording.  See the images for the simple steps – click to enlarge. Record Console Configurations to a File Review the Recordings and Make Slight Modifications In order to make the recorded .py file directly callable as a stand-alone script I added calls to the connect() and edit() functions at the beginning and calls to disconnect() and exit() at the end – otherwise the main section of the script was provided by the console recording.  Below is the resulting file I saved as d:/temp/wm.py connect('weblogic','welcome1', 't3://localhost:7001') edit() startEdit()   cd('/SelfTuning/wl_server') cmo.createMaxThreadsConstraint('MaxThreadsConstraint-0')   cd('/SelfTuning/wl_server/MaxThreadsConstraints/MaxThreadsConstraint-0') set('Targets',jarray.array([ObjectName('com.bea:Name=examplesServer,Type=Server')], ObjectName)) cmo.setCount(5) cmo.unSet('ConnectionPoolName')   cd('/SelfTuning/wl_server') cmo.createWorkManager('WorkManager-0') cd('/SelfTuning/wl_server/WorkManagers/WorkManager-0') set('Targets',jarray.array([ObjectName('com.bea:Name=examplesServer,Type=Server')], ObjectName))   cmo.setMaxThreadsConstraint(getMBean('/SelfTuning/wl_server/MaxThreadsConstraints/MaxThreadsConstraint-0')) cmo.setIgnoreStuckThreads(false)   activate() disconnect() exit() Run the Script If you want to test it be sure to delete the Work Manager and MaxThreadConstraint that you had previously created in the console.  Do something like the following - set up the environment and tell WLST to execute the script which happens in the first 2 lines, the rest doesn’t require any user input: D:\Oracle\wls11g\wlserver_10.3\samples\domains\wl_server\bin>setDomainEnv.cmd D:\Oracle\wls11g\wlserver_10.3\samples\domains\wl_server>java weblogic.WLST d:\temp\wm.py   Initializing WebLogic Scripting Tool (WLST) ...   Welcome to WebLogic Server Administration Scripting Shell   Type help() for help on available commands   Connecting to t3://localhost:7001 with userid weblogic ... Successfully connected to Admin Server 'examplesServer' that belongs to domain 'wl_server'.   Warning: An insecure protocol was used to connect to the server. To ensure on-the-wire security, the SSL port or Admin port should be used instead.   Location changed to edit tree. This is a writable tree with DomainMBean as the root. To make changes you will need to start an edit session via startEdit().   For more help, use help(edit)   Starting an edit session ... Started edit session, please be sure to save and activate your changes once you are done. Activating all your changes, this may take a while ... The edit lock associated with this edit session is released once the activation is completed. Activation completed Disconnected from weblogic server: examplesServer     Exiting WebLogic Scripting Tool.   Now if you go back and look in the console the changes have been made and we now have a compete script.  Of course there is a full MBean reference and you can learn the nuances of jython and WLST, but why not the WLS console do most of the work for you!  Happy scripting.

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• ASP.NET Web API - Screencast series Part 3: Delete and Update

  - by Jon Galloway

  We're continuing a six part series on ASP.NET Web API that accompanies the getting started screencast series. This is an introductory screencast series that walks through from File / New Project to some more advanced scenarios like Custom Validation and Authorization. The screencast videos are all short (3-5 minutes) and the sample code for the series is both available for download and browsable online. I did the screencasts, but the samples were written by the ASP.NET Web API team. In Part 1 we looked at what ASP.NET Web API is, why you'd care, did the File / New Project thing, and did some basic HTTP testing using browser F12 developer tools. In Part 2 we started to build up a sample that returns data from a repository in JSON format via GET methods. In Part 3, we'll start to modify data on the server using DELETE and POST methods. So far we've been looking at GET requests, and the difference between standard browsing in a web browser and navigating an HTTP API isn't quite as clear. Delete is where the difference becomes more obvious. With a "traditional" web page, to delete something'd probably have a form that POSTs a request back to a controller that needs to know that it's really supposed to be deleting something even though POST was really designed to create things, so it does the work and then returns some HTML back to the client that says whether or not the delete succeeded. There's a good amount of plumbing involved in communicating between client and server. That gets a lot easier when we just work with the standard HTTP DELETE verb. Here's how the server side code works: public Comment DeleteComment(int id) { Comment comment; if (!repository.TryGet(id, out comment)) throw new HttpResponseException(HttpStatusCode.NotFound); repository.Delete(id); return comment; } If you look back at the GET /api/comments code in Part 2, you'll see that they start the exact same because the use cases are kind of similar - we're looking up an item by id and either displaying it or deleting it. So the only difference is that this method deletes the comment once it finds it. We don't need to do anything special to handle cases where the id isn't found, as the same HTTP 404 handling works fine here, too. Pretty much all "traditional" browsing uses just two HTTP verbs: GET and POST, so you might not be all that used to DELETE requests and think they're hard. Not so! Here's the jQuery method that calls the /api/comments with the DELETE verb: $(function() { $("a.delete").live('click', function () { var id = $(this).data('comment-id'); $.ajax({ url: "/api/comments/" + id, type: 'DELETE', cache: false, statusCode: { 200: function(data) { viewModel.comments.remove( function(comment) { return comment.ID == data.ID; } ); } } }); return false; }); }); So in order to use the DELETE verb instead of GET, we're just using $.ajax() and setting the type to DELETE. Not hard. But what's that statusCode business? Well, an HTTP status code of 200 is an OK response. Unless our Web API method sets another status (such as by throwing the Not Found exception we saw earlier), the default response status code is HTTP 200 - OK. That makes the jQuery code pretty simple - it calls the Delete action, and if it gets back an HTTP 200, the server-side delete was successful so the comment can be deleted. Adding a new comment uses the POST verb. It starts out looking like an MVC controller action, using model binding to get the new comment from JSON data into a c# model object to add to repository, but there are some interesting differences. public HttpResponseMessage<Comment> PostComment(Comment comment) { comment = repository.Add(comment); var response = new HttpResponseMessage<Comment>(comment, HttpStatusCode.Created); response.Headers.Location = new Uri(Request.RequestUri, "/api/comments/" + comment.ID.ToString()); return response; } First off, the POST method is returning an HttpResponseMessage<Comment>. In the GET methods earlier, we were just returning a JSON payload with an HTTP 200 OK, so we could just return the  model object and Web API would wrap it up in an HttpResponseMessage with that HTTP 200 for us (much as ASP.NET MVC controller actions can return strings, and they'll be automatically wrapped in a ContentResult). When we're creating a new comment, though, we want to follow standard REST practices and return the URL that points to the newly created comment in the Location header, and we can do that by explicitly creating that HttpResposeMessage and then setting the header information. And here's a key point - by using HTTP standard status codes and headers, our response payload doesn't need to explain any context - the client can see from the status code that the POST succeeded, the location header tells it where to get it, and all it needs in the JSON payload is the actual content. Note: This is a simplified sample. Among other things, you'll need to consider security and authorization in your Web API's, and especially in methods that allow creating or deleting data. We'll look at authorization in Part 6. As for security, you'll want to consider things like mass assignment if binding directly to model objects, etc. In Part 4, we'll extend on our simple querying methods form Part 2, adding in support for paging and querying.

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• Initial Review - Mastering Unreal Technology I: Introduction to Level Design with Unreal Engine 3

  - by Matt Christian

  Recently I purchased 3 large volumes on using the Unreal 3 Engine to create levels and custom games.  This past weekend I cracked the spine of the first and started reading.  Here are my early impressions (I'm ~250 pages into it, with appendices it's about 900). Pros Interestingly, the book starts with an overview of the Unreal engines leading up to Unreal 3 (including Gears of War) and follows with some discussion on planning a mod and what goes into the game development process.  This is nice for an intro to the book and is much preferred rather than a simple chapter detailing what is on the included CD, how to install and setup UnrealEd, etc...  While the chapter on Unreal history and planning can be considered 'fluff', it's much less 'fluffy' than most books provide. I need to mention one thing here that is pretty crucial in the way I'm going to continue reviewing this book.  Most technical books like this are used as a shelf reference; as a thick volume you use for looking up techniques every now and again.  Even so, I prefer reading from cover to cover, including chapters I may already be knowledgable on (I'm sure this is typical for most people).  If there was a chapter on installing UnrealEd (the previously mentioned 'fluff'), I would probably force myself to read it, even though I've installed the game and engine multiple times on different systems. Chapter 3 is where we really get to the introduction piece of UnrealEd, creating your first basic level.  This large chapter details creating two small rooms, adding static meshes, adding lighting, creating and adding particle emitters, creating a door that animates with Unreal Matinee and Kismet, static meshes with physics, and other little additions to make your level look less beginner.  This really is a chapter that overviews the entire rest of the book, as each chapter following details the creation and intermediate usages of Static Meshes, Materials, Lighting, etc... One other very nice part to this book is the way the tutorials are setup.  Each tutorial builds off the previous and all are step-by-step.  If you haven't completed one yet, you can find all the starting files on the CD that comes with the book. Cons While the description of the overview chapter (Chapter 3) is fresh in your mind, let me start the cons by saying this chapter is setup extremely confusing for the noob.  At one point, you end up creating a door mesh and setting it up as a InteropMesh so that it is ready to be animated, only to switch to particles and spend a good portion of time working on a different piece of the level.  Yes, this is actually how I develop my levels (jumping back and forth), though it's very odd for a book to jump out of sequence. The next item might be a positive or a negative depending on your skill level with UnrealEd.  Most of the introduction to the editor layout is found in one of the Appendices instead of before Chapter 3.  For new readers, this might lead to confusion as Appendix A would typically be read between Chapter 2 and 3.  However, this is a positive for those with some experience in UnrealEd as they don't have to force themselves through a 'learn every editor button' chapter.  I'm listing this in the Cons section as the book is 'Introduction to...' and is probably going to be directed toward a lot of very beginner developers. Finally, there's a lack of general description to a lot of the underlying engine and what each piece in UnrealEd is or does.  Sometimes you'll be performing Tutorial after Tutorial with barely a paragraph in between describing ANY of what you've just done.  Tutorial 1.1 Step 6 says to press Button X, so you do.  But why?  This is in part a problem with the structure of the tutorials rather than the content of the book.  Since the tutorials are so focused on a step-by-step (or procedural) description of a process, you learn the process and not why you're doing that.  For example, you might learn how to size a material to a surface, but will only learn what buttons to press and not what each one does. This becomes extremely apparent in the chapter on Static Meshes as most of the chapter is spent in 3D Studio Max.  Since there are books on 3DSM and modelling, the book really only tells you the steps and says to go grab a book on modelling if you're really interested in 3DSM.  Again, I've learned the process to develop my own meshes in 3DSM, but I don't know the why behind the steps. Conclusion So far the book is very good though I would have a hard time recommending it to a complete beginner.  I would suggest anyone looking at this book (obviously including the other 2, more advanced volumes) to pick up a copy of UDK or Unreal 3 (available online or via download services such as Steam) and watch some online tutorials and play with it first.  You'll find plenty of online videos available that were created by the authors and may suit as a better introduction to the editor.

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• My History with Agile

  - by Robert May

  I’m going to write my history with Agile here.  That way, in future posts, I can refer back to it, instead of typing it out in the post that contains information you may actually want to read.  Note that I’m actually a pretty senior developer, and do lots of technical interviews.  I’m an Agile fan because of the difference it makes in peoples lives and the improvement in quality it brings, and I’ll sacrifice my technological advance to help teams. Management History I started management pretty early in my career, starting with the first job that I ever had.  I actually do NOT have a CS or similar degree.  I have a Bachelor’s of Business Administration with an emphasis in Computer Information Systems. My first management gigs were around call center work and were very schedule oriented.  I didn’t understand the true value of teams, and I’m ashamed to admit, I actually installed a fingerprint scanner as a time clock in this job.  I shudder to think of the impact that I had on the team spirit.  I didn’t even trust them enough to fill out their time cards correctly.  How sad. I was managing nearly 100 people in this position, with the help of a great set of subordinates. I did try to come up with reward programs for the team, but again, didn’t understand the concept of team, so instead of letting the team determine how the rewards should work, I mandated from on high, which isn’t a good thing. I was told that I wasn’t the type that would be a good manager by people whom I respected a lot.  They said it because I was a computer geek, since they don’t understand good management either, but in retrospect, they were right about me then.  I was too green. After my first job, I went on to other jobs and with the exception of one job, I’ve managed people at them all.  The rest of the management story is important for understanding agile, so I’ll save it for my next post. Technical History I’ve been in software development for many, many years.  I technically started programming on a commodore 64 in basic.  I didn’t know that I was programming, but I was sure having fun.  That was followed by batch files, Gorilla hacking (I always had to win), WordPerfect Macro programming and other things that taught me the basics. My first “real” job was with a telephone company, and that’s where I made my first database application in DataEase, wrote my first VBA app and started using real programming tools, like turbo pascal, vb3-vb5, and semi-real tools like RPG and VisualRPG.  I wrote my first web page in 1994, and built my first data driven web page in 1995 using perlDB.  You really can do anything with Perl.  At this time, I also started a Linux based internet service provider that is still in operation today.  One of the people I worked with is now a Microsoft employee building and designing frameworks you probably know well.  Smart guy.  I also built my first ASP applications connecting to Sql Server 6.5, setup Exchange 5.5 for the company, and many other system administration stuff.  I’m a programmer by choice, mostly because I don’t really like PC support. From there, I went on to a large state agency.  I got to see and maintain true waterfall projects.  5 years of maintaining the 200 VB COM+ (MTS, actually) dlls that were used to calculate a single number is a long time.  That was all Microsoft DNS technologies.  SQL Server and VB6 were the tools of choice, although .net started to be a factor near the end of employment.  I did some heavy XML work at this job and even wrote an XSD parser and validator in VB6 that was a shim until MSXML 3.0 came out.  Prior to 3.0, XSD’s weren’t supported, and I didn’t want to write DTDs. Ironically, jobs after this were more generic.  I pretty much settled in on the .net framework and revisions of it.  Lots of WPF, some silverlight, lots of ASP.NET, some SQL Azure, lots of SQL Server, some Oracle, but I don’t think that I was as passionate about development and technologies.  I was more into the management of development.  I like people. Technorati Tags: Agile,history

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• My Tech Ed North America Preview - Content Edition

  - by Chris Gardner

  As I promised in my last post, I feel the need to give you a rundown on all the technical content I am looking forward to checking out at Tech Ed this year. We shall start with the content I know I'll be able to see. This would be some demo stations in the Technical Learning Center. I will DEFINITELY be checking out the Windows Phone Device Bar. I will admit that I am a bit of a phone snob, and I just want to manhandle all that sexy, sexy tech. I am also planning on talking to the Windows Phone team and the Azure team. Year after year, I end up spending more time in either the TLC or taking certification tests than anywhere else. This leads me to the one "Exam Cram" session I hope to attend. There is a session to cram for 70-599: Designing and Developing Windows Phone Applications. I know this seems odd. I'm (sort of) an XNA guru. However, I'm not that up on my Silverlight. I know enough to add Silverlight to an XNA project. Now, let's talk breakout sessions. We always need to keep track of where we're going. I know, I talk about solving problems over forcing buzz words. However, it is important to know what those buzz words before you tell people not to use them. For this, we will look to the "What's New in Visual Studio 11" and "What's New in Microsoft .NET Framework 4.5." Of course, we do talk bad about buzz words around here. For this, I'm really looking forward to "Visual C#/Visual Basic: Becoming a Guru with Existing Features." I still have .NET 2 tricks that are crucial to my internal libraries. In depth knowledge will NEVER trump shortcut libraries. There is a session in ASP.NET for phones and tablets. For those of you that have not tried to use ASP.NET on a mobile device, there is one thing you really need to understand. Mobile devices don't use scroll bars. That's right; the thing with the least screen real estate doesn't use scroll bars. Thus, I am hoping this session will give some good advice in having an ASP.NET site target both mobile and desktop. The last "business only" session "The Accidental Team Foundation Server Admin." T & W Operations is a VERY small business. As such, I am the TFS admin because I'm the developer that is also the SQL Guru. I keep my server up, but it'd be nice to know some really cool tricks for the part time guy. This leads us the the fun sessions. Coding4Fun has a Kinect session. The Twitter followers will remember that I now have a Kinect for Windows sitting on my desk at work. I have gotten pretty handy with the device, but I KNOW I'm missing some good stuff. Finally, we come to Brian Prince's session on "Making Crazy Money with Games and the Cloud." Never mind the fact that we're using Azure at work. Never mind the fact that I'm actually using the cloud in a game. Never mind the fact that the session has the terms "Crazy Money" and "Games" in the title. If you've never seen Brian Prince speak, you're missing out. In the Hands-on-Labs, we are not allowed to make our own schedule. Instead, we're asked what sessions we can't miss, and they try to schedule around those times. This was the one session I said I couldn't miss. This should complete the technical content for the conference. Coming soon, I'll dig into the certifications I hope to attain. Then, we'll talk about the social activities for the week. Here's a preview of that. I am a member of The Krewe...

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• JavaScript Intellisense Improvements with VS 2010

  - by ScottGu

  This is the twentieth in a series of blog posts I’m doing on the upcoming VS 2010 and .NET 4 release.  Today’s blog post covers some of the nice improvements coming with JavaScript intellisense with VS 2010 and the free Visual Web Developer 2010 Express.  You’ll find with VS 2010 that JavaScript Intellisense loads much faster for large script files and with large libraries, and that it now provides statement completion support for more advanced scenarios compared to previous versions of Visual Studio. [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] Improved JavaScript Intellisense Providing Intellisense for a dynamic language like JavaScript is more involved than doing so with a statically typed language like VB or C#.  Correctly inferring the shape and structure of variables, methods, etc is pretty much impossible without pseudo-executing the actual code itself – since JavaScript as a language is flexible enough to dynamically modify and morph these things at runtime.  VS 2010’s JavaScript code editor now has the smarts to perform this type of pseudo-code execution as you type – which is how its intellisense completion is kept accurate and complete.  Below is a simple walkthrough that shows off how rich and flexible it is with the final release. Scenario 1: Basic Type Inference When you declare a variable in JavaScript you do not have to declare its type.  Instead, the type of the variable is based on the value assigned to it.  Because VS 2010 pseudo-executes the code within the editor, it can dynamically infer the type of a variable, and provide the appropriate code intellisense based on the value assigned to a variable. For example, notice below how VS 2010 provides statement completion for a string (because we assigned a string to the “foo” variable): If we later assign a numeric value to “foo” the statement completion (after this assignment) automatically changes to provide intellisense for a number: Scenario 2: Intellisense When Manipulating Browser Objects It is pretty common with JavaScript to manipulate the DOM of a page, as well as work against browser objects available on the client.  Previous versions of Visual Studio would provide JavaScript statement completion against the standard browser objects – but didn’t provide much help with more advanced scenarios (like creating dynamic variables and methods).  VS 2010’s pseudo-execution of code within the editor now allows us to provide rich intellisense for a much broader set of scenarios. For example, below we are using the browser’s window object to create a global variable named “bar”.  Notice how we can now get intellisense (with correct type inference for a string) with VS 2010 when we later try and use it: When we assign the “bar” variable as a number (instead of as a string) the VS 2010 intellisense engine correctly infers its type and modifies statement completion appropriately to be that of a number instead: Scenario 3: Showing Off Because VS 2010 is psudo-executing code within the editor, it is able to handle a bunch of scenarios (both practical and wacky) that you throw at it – and is still able to provide accurate type inference and intellisense. For example, below we are using a for-loop and the browser’s window object to dynamically create and name multiple dynamic variables (bar1, bar2, bar3…bar9).  Notice how the editor’s intellisense engine identifies and provides statement completion for them: Because variables added via the browser’s window object are also global variables – they also now show up in the global variable intellisense drop-down as well: Better yet – type inference is still fully supported.  So if we assign a string to a dynamically named variable we will get type inference for a string.  If we assign a number we’ll get type inference for a number.  Just for fun (and to show off!) we could adjust our for-loop to assign a string for even numbered variables (bar2, bar4, bar6, etc) and assign a number for odd numbered variables (bar1, bar3, bar5, etc): Notice above how we get statement completion for a string for the “bar2” variable.  Notice below how for “bar1” we get statement completion for a number:   This isn’t just a cool pet trick While the above example is a bit contrived, the approach of dynamically creating variables, methods and event handlers on the fly is pretty common with many Javascript libraries.  Many of the more popular libraries use these techniques to keep the size of script library downloads as small as possible.  VS 2010’s support for parsing and pseudo-executing libraries that use these techniques ensures that you get better code Intellisense out of the box when programming against them. Summary Visual Studio 2010 (and the free Visual Web Developer 2010 Express) now provide much richer JavaScript intellisense support.  This support works with pretty much all popular JavaScript libraries.  It should help provide a much better development experience when coding client-side JavaScript and enabling AJAX scenarios within your ASP.NET applications. Hope this helps, Scott P.S. You can read my previous blog post on VS 2008’s JavaScript Intellisense to learn more about our previous JavaScript intellisense (and some of the scenarios it supported).  VS 2010 obviously supports all of the scenarios previously enabled with VS 2008.

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• Simultaneously calling multiple methods on a WCF service from silverlight

  - by ola karlsson

  A while back I had to debug some performance issues in an existing Silverlight app, as the problem / solution was a bit obscure and finding info about it was quite tricky, I thought I’d share, maybe it can help the next person with this problem. The App On start, the app would do a number of calls to different methods on a WCF service, this to populate the UI with the necessary data. Recently one of those services had been changed and was now taking quite a bit longer than it used to. This was resulting in quite a long loading time for the whole UI, which was set up so it wouldn’t let the user interact with anything, until all the service calls had finished. First I broke out the longer running service call from the others, then removed the constraint that it had to be loaded for the UI in general to become responsive. I also added a loading indicator just on that area of the UI, thinking that the main UI would load while this particular section could keep loading independently. The Problem However this is where things started to get a bit strange. I found that even after these changes, the main UI wouldn’t activate until the long running call returned. So now, I did what I should have done to start with, I got Fiddler out and had a look at what was really happening. What I found was that, once the call to the long running service method was placed, all subsequent call were waiting for that one to return before executing. Not having really worked with WCF previously or knowing much about it in general, I was stumped… I knew of the issues where Silverlight is restricted by the browsers networking features in regards to number of simultaneous connections etc. However that just didn’t seem to be the issue here, you can clearly see in Fiddler that there’s numerous calls, but they’re just not returning. I thought of the problem maybe being in the WCF service, but the calls were really not that complicated and surely the service should be able to handle a lot more than what I was throwing at it! So I did what every developer does in this type of scenario, I hit the search engines. I did a whole bunch of searching on things like “multiple simultaneous WCF calls from Silverlight” and “Calling long running WCF services from Silverlight” etc. etc. This however, pretty much got me nowhere, I found a whole heap of resources on how to do WCF calls from Silverlight but most of them were very basic and of no use what so ever. The fog is clearing It wasn’t until I came across the term “ WCF blocking calls” and started incorporating that in my searches I started to get somewhere. Those searches quite quickly brought me to the following thread in the Silverlight forum “Long-running WCF call blocking subsequent calls” which discussed the exact problem I was facing and the best part, one of the guys there had the solution! The short answer is in the forum post and the guys answering, has also done a more extensive blog post about it called “Silverlight, WCF, and ASP.Net Configuration Gotchas” which covers it very well.  So come on what’s the solution?! I heard you ask, unless you’ve already gone to the links and looked it up ;) The Solution Well, it turns out that the issue is founded in a mix of Silverlight, Asp.Net and WCF, basically if you’re doing multiple calls to a single WCF web-service and you have Asp.Net session state enabled, the calls will be executed sequentially by the service, hence any long running calls will block subsequent ones. So why is Asp.Net session state effecting us, we’re working in Silverlight, right? We'll as mentioned earlier, by default Silverlight uses the browsers networking stack when doing service calls, hence to the WCF service, the call looks like it might as well be coming from a normal Asp.Net. To get around this, we look to a feature introduced in Silverlight 3, namely the Client HTTP Stack. The Client HTTP Stack to the rescue By using the following syntax (for example in our App.xaml.cs, Application_Startup method) WebRequest.RegisterPrefix("http://", WebRequestCreator.ClientHttp); we can set our Silverlight application to use the Client HTTP Stack, which incidentally solves our problem! By using Silverlights own networking stack, rather than that of the browser, we get around the Asp.Net - WCF session state issue. The above code specifies that all calls to addresses starting with “http://” should go through the client stack, this can actually be set more granular and you can specify it to be used only for certain domains etc. Summary The actual solution is well covered in the forum and blog posts I link to above. This post is more about sharing my experience, hopefully helping to spread the word about this and maybe make it a bit easier for the next poor guy with this issue to find the solution. Until next time, Ola

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• Simple Excel Export with EPPlus

  - by Jesse Taber

  Originally posted on: http://geekswithblogs.net/GruffCode/archive/2013/10/30/simple-excel-export-with-epplus.aspxAnyone I’ve ever met who works with an application that sits in front of a lot of data loves it when they can get that data exported to an Excel file for them to mess around with offline. As both developer and end user of a little website project that I’ve been working on, I found myself wanting to be able to get a bunch of the data that the application was collecting into an Excel file. The great thing about being both an end user and a developer on a project is that you can build the features that you really want! While putting this feature together I came across the fantastic EPPlus library. This library is certainly very well known and popular, but I was so impressed with it that I thought it was worth a quick blog post. This library is extremely powerful; it lets you create and manipulate Excel 2007/2010 spreadsheets in .NET code with a high degree of flexibility. My only gripe with the project is that they are not touting how insanely easy it is to build a basic Excel workbook from a simple data source. If I were running this project the approach I’m about to demonstrate in this post would be front and center on the landing page for the project because it shows how easy it really is to get started and serves as a good way to ease yourself in to some of the more advanced features. The website in question uses RavenDB, which means that we’re dealing with POCOs to model the data throughout all layers of the application. I love working like this so when it came time to figure out how to export some of this data to an Excel spreadsheet I wanted to find a way to take an IEnumerable<T> and just have it dumped to Excel with each item in the collection being modeled as a single row in the Excel worksheet. Consider the following class: public class Employee { public int Id { get; set; } public string Name { get; set; } public decimal HourlyRate { get; set; } public DateTime HireDate { get; set; } } Now let’s say we have a collection of these represented as an IEnumerable<Employee> and we want to be able to output it to an Excel file for offline querying/manipulation. As it turns out, this is dead simple to do with EPPlus. Have a look: public void ExportToExcel(IEnumerable<Employee> employees, FileInfo targetFile) { using (var excelFile = new ExcelPackage(targetFile)) { var worksheet = excelFile.Workbook.Worksheets.Add("Sheet1"); worksheet.Cells["A1"].LoadFromCollection(Collection: employees, PrintHeaders: true); excelFile.Save(); } } That’s it. Let’s break down what’s going on here: Create a ExcelPackage to model the workbook (Excel file). Note that the ‘targetFile’ value here is a FileInfo object representing the location on disk where I want the file to be saved. Create a worksheet within the workbook. Get a reference to the top-leftmost cell (addressed as A1) and invoke the ‘LoadFromCollection’ method, passing it our collection of Employee objects. Behind the scenes this is reflecting over the properties of the type provided and pulling out any public members to become columns in the resulting Excel output. The ‘PrintHeaders’ parameter tells EPPlus to grab the name of the property and put it in the first row. Save the Excel file All of the heavy lifting here is being done by the ‘LoadFromCollection’ method, and that’s a good thing. Now, this was really easy to do, but it has some limitations. Using this approach you get a very plain, un-styled Excel worksheet. The column widths are all set to the default. The number format for all cells is ‘General’ (which proves particularly interesting if you have a DateTime property in your data source). I’m a “no frills” guy, so I wasn’t bothered at all by trading off simplicity for style and formatting. That said, EPPlus has tons of samples that you can download that illustrate how to apply styles and formatting to cells and a ton of other advanced features that are way beyond the scope of this post.

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• HTG Explains: Why is Printer Ink So Expensive?

  - by Chris Hoffman

  Printer ink is expensive, more expensive per drop than fine champagne or even human blood. If you haven’t gone paperless, you’ll notice that you’re paying a lot for new ink cartridges — more than seems reasonable. Purchasing the cheapest inkjet printer and buying official ink cartridge replacements is the most expensive thing you can do. There are ways to save money on ink if you must continue to print documents. Cheap Printers, Expensive Ink Ink jet printers are often very cheap. That’s because they’re sold at cost, or even at a loss — the manufacturer either makes no profit from the printer itself or loses money. The manufacturer will make most of its money from the printer cartridges you buy later. Even if the company does make a bit of money from each printer sold, it makes a much larger profit margin on ink. Rather than selling you a printer that may be rather expensive, they want to sell you a cheap printer and make money on an ongoing basis by providing expensive printer ink. It’s been compared to the razor model — sell a razor cheaply and mark up the razor blades. Rather than making a one-time profit on the razor, you’ll make continuing profit as the customer keeps buying razor blade replacements — or ink, in this case. Many printer manufacturers go out of their way to make it difficult for you to use unofficial ink cartridges, building microchips into their official ink cartridges. If you use an unofficial cartridge or refill an official cartridge, the printer may refuse to use it. Lexmark once argued in court that unofficial microchips that enable third-party ink cartridges would violate their copyright and Lexmark has argued that creating an unofficial microchip to bypass this restriction on third-party ink would violate Lexmark’s copyright and be illegal under the US DMCA. Luckily, they lost this argument. What Printer Companies Say Printer companies have put forth their own arguments in the past, attempting to justify the high cost of official ink cartridges and microchips that block any competition. In a Computer World story from 2010, HP argued that they spend a billion dollars each year on “ink research and development.” They point out that printer ink “must be formulated to withstand heating to 300 degrees, vaporization, and being squirted at 30 miles per hour, at a rate of 36,000 drops per second, through a nozzle one third the size of a human hair. After all that it must dry almost instantly on the paper.” They also argue that printers have become more efficient and use less ink to print, while third-party cartridges are less reliable. Companies that use microchips in their ink cartridges argue that only the microchip has the ability to enforce an expiration date, preventing consumers from using old ink cartridges. There’s something to all these arguments, sure — but they don’t seem to justify the sky-high cost of printer ink or the restriction on using third-party or refilled cartridges. Saving Money on Printing Ultimately, the price of something is what people are willing to pay and printer companies have found that most consumers are willing to pay this much for ink cartridge replacements. Try not to fall for it: Don’t buy the cheapest inkjet printer. Consider your needs when buying a printer and do some research. You’ll save more money in the long run. Consider these basic tips to save money on printing: Buy Refilled Cartridges: Refilled cartridges from third parties are generally much cheaper. Printer companies warn us away from these, but they often work very well. Refill Your Own Cartridges: You can get do-it-yourself kits for refilling your own printer ink cartridges, but this can be messy. Your printer may refuse to accept a refilled cartridge if the cartridge contains a microchip. Switch to a Laser Printer: Laser printers use toner, not ink cartridges. If you print a lot of black and white documents, a laser printer can be cheaper. Buy XL Cartridges: If you are buying official printer ink cartridges, spend more money each time. The cheapest ink cartridges won’t contain much ink at all, while larger “XL” ink cartridges will contain much more ink for only a bit more money. It’s often cheaper to buy in bulk. Avoid Printers With Tri-Color Ink Cartridges: If you’re printing color documents, you’ll want to get a printer that uses separate ink cartridges for all its colors. For example, let’s say your printer has a “Color” cartridge that contains blue, green, and red ink. If you print a lot of blue documents and use up all your blue ink, the Color cartridge will refuse to function — now all you can do is throw away your cartridge and buy a new one, even if the green and red ink chambers are full. If you had a printer with separate color cartridges, you’d just have to replace the blue cartridge. If you’ll be buying official ink cartridges, be sure to compare the cost of cartridges when buying a printer. The cheapest printer may be more expensive in the long run. Of course, you’ll save the most money if you stop printing entirely and go paperless, keeping digital copies of your documents instead of paper ones. Image Credit: Cliva Darra on Flickr     

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• An Alphabet of Eponymous Aphorisms, Programming Paradigms, Software Sayings, Annoying Alliteration

  - by Brian Schroer

  Malcolm Anderson blogged about “Einstein’s Razor” yesterday, which reminded me of my favorite software development “law”, the name of which I can never remember. It took much Wikipedia-ing to find it (Hofstadter’s Law – see below), but along the way I compiled the following list: Amara’s Law: We tend to overestimate the effect of a technology in the short run and underestimate the effect in the long run. Brook’s Law: Adding manpower to a late software project makes it later. Clarke’s Third Law: Any sufficiently advanced technology is indistinguishable from magic. Law of Demeter: Each unit should only talk to its friends; don't talk to strangers. Einstein’s Razor: “Make things as simple as possible, but not simpler” is the popular paraphrase, but what he actually said was “It can scarcely be denied that the supreme goal of all theory is to make the irreducible basic elements as simple and as few as possible without having to surrender the adequate representation of a single datum of experience”, an overly complicated quote which is an obvious violation of Einstein’s Razor. (You can tell by looking at a picture of Einstein that the dude was hardly an expert on razors or other grooming apparati.) Finagle's Law of Dynamic Negatives: Anything that can go wrong, will—at the worst possible moment. - O'Toole's Corollary: The perversity of the Universe tends towards a maximum. Greenspun's Tenth Rule: Any sufficiently complicated C or Fortran program contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Common Lisp. (Morris’s Corollary: “…including Common Lisp”) Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's Law. Issawi’s Omelet Analogy: One cannot make an omelet without breaking eggs - but it is amazing how many eggs one can break without making a decent omelet. Jackson’s Rules of Optimization: Rule 1: Don't do it. Rule 2 (for experts only): Don't do it yet. Kaner’s Caveat: A program which perfectly meets a lousy specification is a lousy program. Liskov Substitution Principle (paraphrased): Functions that use pointers or references to base classes must be able to use objects of derived classes without knowing it Mason’s Maxim: Since human beings themselves are not fully debugged yet, there will be bugs in your code no matter what you do. Nils-Peter Nelson’s Nil I/O Rule: The fastest I/O is no I/O.    Occam's Razor: The simplest explanation is usually the correct one. Parkinson’s Law: Work expands so as to fill the time available for its completion. Quentin Tarantino’s Pie Principle: “…you want to go home have a drink and go and eat pie and talk about it.” (OK, he was talking about movies, not software, but I couldn’t find a “Q” quote about software. And wouldn’t it be cool to write a program so great that the users want to eat pie and talk about it?) Raymond’s Rule: Computer science education cannot make anybody an expert programmer any more than studying brushes and pigment can make somebody an expert painter.  Sowa's Law of Standards: Whenever a major organization develops a new system as an official standard for X, the primary result is the widespread adoption of some simpler system as a de facto standard for X. Turing’s Tenet: We shall do a much better programming job, provided we approach the task with a full appreciation of its tremendous difficulty, provided that we respect the intrinsic limitations of the human mind and approach the task as very humble programmers.  Udi Dahan’s Race Condition Rule: If you think you have a race condition, you don’t understand the domain well enough. These rules didn’t exist in the age of paper, there is no reason for them to exist in the age of computers. When you have race conditions, go back to the business and find out actual rules. Van Vleck’s Kvetching: We know about as much about software quality problems as they knew about the Black Plague in the 1600s. We've seen the victims' agonies and helped burn the corpses. We don't know what causes it; we don't really know if there is only one disease. We just suffer -- and keep pouring our sewage into our water supply. Wheeler’s Law: All problems in computer science can be solved by another level of indirection... Except for the problem of too many layers of indirection. Wheeler also said “Compatibility means deliberately repeating other people's mistakes.”. The Wrong Road Rule of Mr. X (anonymous): No matter how far down the wrong road you've gone, turn back. Yourdon’s Rule of Two Feet: If you think your management doesn't know what it's doing or that your organisation turns out low-quality software crap that embarrasses you, then leave. Zawinski's Law of Software Envelopment: Every program attempts to expand until it can read mail. Zawinski is also responsible for “Some people, when confronted with a problem, think 'I know, I'll use regular expressions.' Now they have two problems.” He once commented about X Windows widget toolkits: “Using these toolkits is like trying to make a bookshelf out of mashed potatoes.”

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• HTML5 and CSS3 Editing in Windows Live Writer

  - by Rick Strahl

  Windows Live Writer is a wonderful tool for editing blog posts and getting them posted to your blog. What makes it nice is that it has a small set of useful features, plus a simple plug-in model that has spawned many useful add-ins. Small tool with a reasonably decent plug-in model to extend equals a great solution to a simple problem. If you're running Windows, have a blog and aren’t using Live Writer you’re probably doing it wrong…One of Live Writer’s nice features is that it can download your blog’s CSS for preview and edit displays. It lets you edit your content inside of the context of that CSS using the WYSIWYG editor, so your content actually looks very close to what you’ll see on your blog while you’re editing your post. Unfortunately Live Writer renders the HTML content in the Web Browser Control’s  default IE 7 rendering mode. Yeah you read that right: IE 7 is the default for the Web Browser control and most applications that use it, are stuck in this modus unless the application explicitly overrides this default. The Web Browser control does not use the version of Internet Explorer installed on the system (IE 10 on my Win8 machine) but uses IE 7 mode for ‘compatibility’ for old applications.If you are importing your blog’s CSS that may suck if you’re using rich HTML 5 and CSS 3 formatting. Hack the Registry to get Live Writer to render using IE 9 or 10In order to get Live Writer (or any other application that uses the Web Browser Control for that matter) to render you can apply a registry hack that overrides the Web Browser Control engine usage for a specific application. I wrote about this in detail in a previous blog post a couple of years back.Here’s how you can set up Windows Live Writer to render your CSS 3 by making a change in your registry:The above is for setup on a 64 bit machine, where I configure Live Writer which is a 32 bit application for using IE 10 rendering. The keys set are as follows:32bit Configuration on 64 bit machine:HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Internet Explorer\Main\FeatureControl\FEATURE_BROWSER_EMULATIONKey: WindowsLiveWriter.exeValue: 9000 or 10000  (IE 9 or 10 respectively) (DWORD value)On a 32 bit only machine: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main\FeatureControl\FEATURE_BROWSER_EMULATIONKey: WindowsLiveWriter.exeValue: 9000 or 10000  (IE 9 or 10 respectively) (DWORD value)Use decimal values of 9000, 10000 or 11000 to specify specific versions of Internet Explorer. This is a minor tweak, but it’s nice to actually see my blog posts now with the proper CSS formatting intact. Notice the rounded borders and shadow on the code blocks as well as the overflow-x and scrollbars that show up. In this particular case I can see what the code blocks actually look like in a specific resolution – much better than in the old plain view which just chopped things off at the end of the window frame. There are a few other elements that now show properly in the editor as well including block quotes and note boxes that I occasionally use. It’s minor stuff, but it makes the editing experience better yet and closer to the final things so there are less republish operations than I previously had. Sweet!Note that this approach of putting an IE version override into the registry works with most applications that use the Web Browser control. If you are using the Web Browser control in your own applications, it’s a good idea to switch the browser to a more recent version so you can take advantage of HTML 5 and CSS 3 in your browser displayed content by automatically setting this flag in the registry or as part of the application’s startup routine if not dedicated setup tool is used. At the very least you might set it to 9000 (IE 9) which supports most of the basic CSS3 features and is a decent baseline that works for most Windows 7 and 8 machines. If running pre-IE9, the browser will fall back to IE7 rendering and look bad but at least more recent browsers will see an improved experience.I’m surprised that there aren’t more vendors and third party apps using this feature. You can see in my first screen shot that there are only very few entries in the registry key group on my machine – any other apps use the Web Browser control are using IE7. Go figure. Certainly Windows Live Writer should be writing this key into the registry automatically as part of installation to support this functionality out of the box, but alas since it does not, this registry hack lets you get your way anyway…Resources.reg Files to register Live Write Browser Emulation (set for IE9)Specifying Internet Explorer Version for ApplicationsSnagIt LiveWriter Plug-inDownload Windows Live WriterDownload Windows Live Writer with Chocolatey© Rick Strahl, West Wind Technologies, 2005-2013Posted in Live Writer  Windows   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Chart Control in ASP.Net 4 – Second Part

  - by sreejukg

    Couple of weeks before, I have written an introduction about the chart control available in .Net framework. In that article, I explained the basic usage of the chart control with a simple example. You can read that article from the url http://weblogs.asp.net/sreejukg/archive/2010/12/31/getting-started-with-chart-control-in-asp-net-4-0.aspx. In this article I am going to demonstrate how one can generate various types of charts that can be generated easily using the ASP.Net chart control. Let us recollect the data sample we were working in the previous sample. The following is the data I used in the previous article. id SaleAmount SalesPerson SaleType SaleDate CompletionStatus (%) 1 1000 Jack Development 2010-01-01 100 2 300 Mills Consultancy 2010-04-14 90 3 4000 Mills Development 2010-05-15 80 4 2500 Mike eMarketting 2010-06-15 40 5 1080 Jack Development 2010-07-15 30 6 6500 Mills Consultancy 2010-08-24 65 In this article I am going to demonstrate various graphical reports generated from this data with the help of chart control. The following are the reports I am going to generate 1. Representation of share of Sales by each Sales person. 2. Representation of share of sales data according to sale type 3. Representation of sales progress over time period I am going to demonstrate how to bind the chart control programmatically. In order to facilitate this, I created an aspx page named “SalesAnalysis.Aspx” to my project. In the page I added the following controls 1. Dropdownlist control – with id ddlAnalysisType, user will use this to choose the type of chart they want to see. 2. A Button control – with id btnSubmit , by clicking this button, the chart based on the dropdownlist selection will be shown to the user 3. A label Control – with id lblMessage, to display the message to the user, initially this will ask the user to select an option and click on the button. 4. Chart control – with id chrtAnalysis, by default, I set visible = false so that during the page load the chart will be hidden to the users. The following is the initial output of the page. Generating chart for salesperson share Now from Visual Studio, I have double clicked on the button; it created the event handler btnSubmit_Click. In the button Submit event handler, I am using a switch case to execute the corresponding SQL statement and bind it to the chart control. The below is the code for generating the sales person share chart using a pie chart. The above code produces the following output The steps for creating the above chart can be summarized as follows. You specify a chart area, then a series and bind the chart to some x and y values. That is it. If you want to control the chart size and position, you can set the properties for the ChartArea.Position element. For e.g. in the previous code, after instantiating the chart area, setting the below code will give you a bigger pie chart. c.Position.Width = 100; c.Position.Height = 100; The width and height values are in percentage. In this case the chart will be generated by utilizing all the width and height of the chart object. See the output updated with the width and height set to 100% each. Generate Chart for sales type share Now for generating the chart according to the sales type, you just need to change the SQL query and x and y values of the chart. The Sql query used is “SELECT SUM(saleAmount) amount, SaleType from SalesData group by SaleType” and the X-Value is amount and Y-Values is SaleType. s.XValueMember = "SaleType"; s.YValueMembers = "amount"; After modifying the above code with these, the following output is generated. Generate Chart for sales progress over time period For generating the progress of sale chart against sales amount / period, line chart is the ideal tool. In order to facilitate the line chart, you can use Chart Type as System.Web.UI.DataVisualization.Charting.SeriesChartType.Line. Also we need to retrieve the amount and sales date from the data source. I have used the following query to facilitate this. “SELECT SaleAmount, SaleDate FROM SalesData” The output for the line chart is as follows Now you have seen how easily you can build various types of charts. Chart control is an excellent one that helps you to bring business intelligence to your applications. What I demonstrated in only a small part of what you can do with the chart control. Refer http://msdn.microsoft.com/en-us/library/dd456632.aspx for further reading. If you want to get the project files in zip format, post your email below. Hope you enjoyed reading this article.

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• Class Loading Deadlocks

  - by tomas.nilsson

  Mattis follows up on his previous post with one more expose on Class Loading Deadlocks As I wrote in a previous post, the class loading mechanism in Java is very powerful. There are many advanced techniques you can use, and when used wrongly you can get into all sorts of trouble. But one of the sneakiest deadlocks you can run into when it comes to class loading doesn't require any home made class loaders or anything. All you need is classes depending on each other, and some bad luck. First of all, here are some basic facts about class loading: 1) If a thread needs to use a class that is not yet loaded, it will try to load that class 2) If another thread is already loading the class, the first thread will wait for the other thread to finish the loading 3) During the loading of a class, one thing that happens is that the <clinit method of a class is being run 4) The <clinit method initializes all static fields, and runs any static blocks in the class. Take the following class for example: class Foo { static Bar bar = new Bar(); static { System.out.println("Loading Foo"); } } The first time a thread needs to use the Foo class, the class will be initialized. The <clinit method will run, creating a new Bar object and printing "Loading Foo" But what happens if the Bar object has never been used before either? Well, then we will need to load that class as well, calling the Bar <clinit method as we go. Can you start to see the potential problem here? A hint is in fact #2 above. What if another thread is currently loading class Bar? The thread loading class Foo will have to wait for that thread to finish loading. But what happens if the <clinit method of class Bar tries to initialize a Foo object? That thread will have to wait for the first thread, and there we have the deadlock. Thread one is waiting for thread two to initialize class Bar, thread two is waiting for thread one to initialize class Foo. All that is needed for a class loading deadlock is static cross dependencies between two classes (and a multi threaded environment): class Foo { static Bar b = new Bar(); } class Bar { static Foo f = new Foo(); } If two threads cause these classes to be loaded at exactly the same time, we will have a deadlock. So, how do you avoid this? Well, one way is of course to not have these circular (static) dependencies. On the other hand, it can be very hard to detect these, and sometimes your design may depend on it. What you can do in that case is to make sure that the classes are first loaded single threadedly, for example during an initialization phase of your application. The following program shows this kind of deadlock. To help bad luck on the way, I added a one second sleep in the static block of the classes to trigger the unlucky timing. Notice that if you uncomment the "//Foo f = new Foo();" line in the main method, the class will be loaded single threadedly, and the program will terminate as it should. public class ClassLoadingDeadlock { // Start two threads. The first will instansiate a Foo object, // the second one will instansiate a Bar object. public static void main(String[] arg) { // Uncomment next line to stop the deadlock // Foo f = new Foo(); new Thread(new FooUser()).start(); new Thread(new BarUser()).start(); } } class FooUser implements Runnable { public void run() { System.out.println("FooUser causing class Foo to be loaded"); Foo f = new Foo(); System.out.println("FooUser done"); } } class BarUser implements Runnable { public void run() { System.out.println("BarUser causing class Bar to be loaded"); Bar b = new Bar(); System.out.println("BarUser done"); } } class Foo { static { // We are deadlock prone even without this sleep... // The sleep just makes us more deterministic try { Thread.sleep(1000); } catch(InterruptedException e) {} } static Bar b = new Bar(); } class Bar { static { try { Thread.sleep(1000); } catch(InterruptedException e) {} } static Foo f = new Foo(); }

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• JavaScript Class Patterns

  - by Liam McLennan

  To write object-oriented programs we need objects, and likely lots of them. JavaScript makes it easy to create objects: var liam = { name: "Liam", age: Number.MAX_VALUE }; But JavaScript does not provide an easy way to create similar objects. Most object-oriented languages include the idea of a class, which is a template for creating objects of the same type. From one class many similar objects can be instantiated. Many patterns have been proposed to address the absence of a class concept in JavaScript. This post will compare and contrast the most significant of them. Simple Constructor Functions Classes may be missing but JavaScript does support special constructor functions. By prefixing a call to a constructor function with the ‘new’ keyword we can tell the JavaScript runtime that we want the function to behave like a constructor and instantiate a new object containing the members defined by that function. Within a constructor function the ‘this’ keyword references the new object being created -  so a basic constructor function might be: function Person(name, age) { this.name = name; this.age = age; this.toString = function() { return this.name + " is " + age + " years old."; }; } var john = new Person("John Galt", 50); console.log(john.toString()); Note that by convention the name of a constructor function is always written in Pascal Case (the first letter of each word is capital). This is to distinguish between constructor functions and other functions. It is important that constructor functions be called with the ‘new’ keyword and that not constructor functions are not. There are two problems with the pattern constructor function pattern shown above: It makes inheritance difficult The toString() function is redefined for each new object created by the Person constructor. This is sub-optimal because the function should be shared between all of the instances of the Person type. Constructor Functions with a Prototype JavaScript functions have a special property called prototype. When an object is created by calling a JavaScript constructor all of the properties of the constructor’s prototype become available to the new object. In this way many Person objects can be created that can access the same prototype. An improved version of the above example can be written: function Person(name, age) { this.name = name; this.age = age; } Person.prototype = { toString: function() { return this.name + " is " + this.age + " years old."; } }; var john = new Person("John Galt", 50); console.log(john.toString()); In this version a single instance of the toString() function will now be shared between all Person objects. Private Members The short version is: there aren’t any. If a variable is defined, with the var keyword, within the constructor function then its scope is that function. Other functions defined within the constructor function will be able to access the private variable, but anything defined outside the constructor (such as functions on the prototype property) won’t have access to the private variable. Any variables defined on the constructor are automatically public. Some people solve this problem by prefixing properties with an underscore and then not calling those properties by convention. function Person(name, age) { this.name = name; this.age = age; } Person.prototype = { _getName: function() { return this.name; }, toString: function() { return this._getName() + " is " + this.age + " years old."; } }; var john = new Person("John Galt", 50); console.log(john.toString()); Note that the _getName() function is only private by convention – it is in fact a public function. Functional Object Construction Because of the weirdness involved in using constructor functions some JavaScript developers prefer to eschew them completely. They theorize that it is better to work with JavaScript’s functional nature than to try and force it to behave like a traditional class-oriented language. When using the functional approach objects are created by returning them from a factory function. An excellent side effect of this pattern is that variables defined with the factory function are accessible to the new object (due to closure) but are inaccessible from anywhere else. The Person example implemented using the functional object construction pattern is: var john = new Person("John Galt", 50); console.log(john.toString()); var personFactory = function(name, age) { var privateVar = 7; return { toString: function() { return name + " is " + age * privateVar / privateVar + " years old."; } }; }; var john2 = personFactory("John Lennon", 40); console.log(john2.toString()); Note that the ‘new’ keyword is not used for this pattern, and that the toString() function has access to the name, age and privateVar variables because of closure. This pattern can be extended to provide inheritance and, unlike the constructor function pattern, it supports private variables. However, when working with JavaScript code bases you will find that the constructor function is more common – probably because it is a better approximation of mainstream class oriented languages like C# and Java. Inheritance Both of the above patterns can support inheritance but for now, favour composition over inheritance. Summary When JavaScript code exceeds simple browser automation object orientation can provide a powerful paradigm for controlling complexity. Both of the patterns presented in this article work – the choice is a matter of style. Only one question still remains; who is John Galt?

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• JavaScript Class Patterns

  - by Liam McLennan

  To write object-oriented programs we need objects, and likely lots of them. JavaScript makes it easy to create objects: var liam = { name: "Liam", age: Number.MAX_VALUE }; But JavaScript does not provide an easy way to create similar objects. Most object-oriented languages include the idea of a class, which is a template for creating objects of the same type. From one class many similar objects can be instantiated. Many patterns have been proposed to address the absence of a class concept in JavaScript. This post will compare and contrast the most significant of them. Simple Constructor Functions Classes may be missing but JavaScript does support special constructor functions. By prefixing a call to a constructor function with the ‘new’ keyword we can tell the JavaScript runtime that we want the function to behave like a constructor and instantiate a new object containing the members defined by that function. Within a constructor function the ‘this’ keyword references the new object being created -  so a basic constructor function might be: function Person(name, age) { this.name = name; this.age = age; this.toString = function() { return this.name + " is " + age + " years old."; }; } var john = new Person("John Galt", 50); console.log(john.toString()); Note that by convention the name of a constructor function is always written in Pascal Case (the first letter of each word is capital). This is to distinguish between constructor functions and other functions. It is important that constructor functions be called with the ‘new’ keyword and that not constructor functions are not. There are two problems with the pattern constructor function pattern shown above: It makes inheritance difficult The toString() function is redefined for each new object created by the Person constructor. This is sub-optimal because the function should be shared between all of the instances of the Person type. Constructor Functions with a Prototype JavaScript functions have a special property called prototype. When an object is created by calling a JavaScript constructor all of the properties of the constructor’s prototype become available to the new object. In this way many Person objects can be created that can access the same prototype. An improved version of the above example can be written: function Person(name, age) { this.name = name; this.age = age; } Person.prototype = { toString: function() { return this.name + " is " + this.age + " years old."; } }; var john = new Person("John Galt", 50); console.log(john.toString()); In this version a single instance of the toString() function will now be shared between all Person objects. Private Members The short version is: there aren’t any. If a variable is defined, with the var keyword, within the constructor function then its scope is that function. Other functions defined within the constructor function will be able to access the private variable, but anything defined outside the constructor (such as functions on the prototype property) won’t have access to the private variable. Any variables defined on the constructor are automatically public. Some people solve this problem by prefixing properties with an underscore and then not calling those properties by convention. function Person(name, age) { this.name = name; this.age = age; } Person.prototype = { _getName: function() { return this.name; }, toString: function() { return this._getName() + " is " + this.age + " years old."; } }; var john = new Person("John Galt", 50); console.log(john.toString()); Note that the _getName() function is only private by convention – it is in fact a public function. Functional Object Construction Because of the weirdness involved in using constructor functions some JavaScript developers prefer to eschew them completely. They theorize that it is better to work with JavaScript’s functional nature than to try and force it to behave like a traditional class-oriented language. When using the functional approach objects are created by returning them from a factory function. An excellent side effect of this pattern is that variables defined with the factory function are accessible to the new object (due to closure) but are inaccessible from anywhere else. The Person example implemented using the functional object construction pattern is: var personFactory = function(name, age) { var privateVar = 7; return { toString: function() { return name + " is " + age * privateVar / privateVar + " years old."; } }; }; var john2 = personFactory("John Lennon", 40); console.log(john2.toString()); Note that the ‘new’ keyword is not used for this pattern, and that the toString() function has access to the name, age and privateVar variables because of closure. This pattern can be extended to provide inheritance and, unlike the constructor function pattern, it supports private variables. However, when working with JavaScript code bases you will find that the constructor function is more common – probably because it is a better approximation of mainstream class oriented languages like C# and Java. Inheritance Both of the above patterns can support inheritance but for now, favour composition over inheritance. Summary When JavaScript code exceeds simple browser automation object orientation can provide a powerful paradigm for controlling complexity. Both of the patterns presented in this article work – the choice is a matter of style. Only one question still remains; who is John Galt?

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