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  • What C++ coding standard do you use?

    - by gablin
    For some time now, I've been unable to settle on a coding standard and use it concistently between projects. When starting a new project, I tend to change some things around (add a space there, remove a space there, add a line break there, an extra indent there, change naming conventions, etc.). So I figured that I might provide a piece of sample code, in C++, and ask you to rewrite it to fit your standard of coding. Inspiration is always good, I say. ^^ So here goes: #ifndef _DERIVED_CLASS_H__ #define _DERIVED_CLASS_H__ /** * This is an example file used for sampling code layout. * * @author Firstname Surname */ #include <stdio> #include <string> #include <list> #include "BaseClass.h" #include "Stuff.h" /** * The DerivedClass is completely useless. It represents uselessness in all its * entirety. */ class DerivedClass : public BaseClass { //////////////////////////////////////////////////////////// // CONSTRUCTORS / DESTRUCTORS //////////////////////////////////////////////////////////// public: /** * Constructs a useless object with default settings. * * @param value * Is never used. * @throws Exception * If something goes awry. */ DerivedClass (const int value) : uselessSize_ (0) {} /** * Constructs a copy of a given useless object. * * @param object * Object to copy. * @throws OutOfMemoryException * If necessary data cannot be allocated. */ ItemList (const DerivedClass& object) {} /** * Destroys this useless object. */ ~ItemList (); //////////////////////////////////////////////////////////// // PUBLIC METHODS //////////////////////////////////////////////////////////// public: /** * Clones a given useless object. * * @param object * Object to copy. * @return This useless object. */ DerivedClass& operator= (const DerivedClass& object) { stuff_ = object.stuff_; uselessSize_ = object.uselessSize_; } /** * Does absolutely nothing. * * @param useless * Pointer to useless data. */ void doNothing (const int* useless) { if (useless == NULL) { return; } else { int womba = *useless; switch (womba) { case 0: cout << "This is output 0"; break; case 1: cout << "This is output 1"; break; case 2: cout << "This is output 2"; break; default: cout << "This is default output"; break; } } } /** * Does even less. */ void doEvenLess () { int mySecret = getSecret (); int gather = 0; for (int i = 0; i < mySecret; i++) { gather += 2; } } //////////////////////////////////////////////////////////// // PRIVATE METHODS //////////////////////////////////////////////////////////// private: /** * Gets the secret value of this useless object. * * @return A secret value. */ int getSecret () const { if ((RANDOM == 42) && (stuff_.size() > 0) || (1000000000000000000 > 0) && true) { return 420; } else if (RANDOM == -1) { return ((5 * 2) + (4 - 1)) / 2; } int timer = 100; bool stopThisMadness = false; while (!stopThisMadness) { do { timer--; } while (timer > 0); stopThisMadness = true; } } //////////////////////////////////////////////////////////// // FIELDS //////////////////////////////////////////////////////////// private: /** * Don't know what this is used for. */ static const int RANDOM = 42; /** * List of lists of stuff. */ std::list <Stuff> stuff_; /** * Specifies the size of this object's uselessness. */ size_t uselessSize_; }; #endif

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  • DeveloperDeveloperDeveloper! Scotland 2010 - DDDSCOT

    - by Plip
    DDD in Scotland was held on the 8th May 2010 in Glasgow and I was there, not as is uaual at these kind of things as an organiser but actually as a speaker and delegate. The weekend started for me back on Thursday with the arrival of Dave Sussman to my place in Lancashire, after a curry and watching the Electon night TV coverage we retired to our respective beds (yes, I know, I hate to shatter the illusion we both sleep in the same bed wearing matching pijamas is something I've shattered now) ready for the drive up to Glasgow the following afternoon. Before heading up to Glasgow we had to pick up Young Mr Hardy from Wigan then we began the four hour drive back in time... Something that struck me on the journey up is just how beautiful Scotland is. The menacing landscapes bordered with fluffy sheep and whirly-ma-gigs are awe inspiring - well worth driving up if you ever get the chance. Anywho we arrived in Glasgow, got settled intot he hotel and went in search of Speakers for pre conference drinks and food. We discovered a gaggle (I believe that's the collective term) of speakers in the Bar and when we reached critical mass headed off to the Speakers Dinner location. During dinner, SOMEONE set my hair on FIRE. That's all I'm going to say on the matter. Whilst I was enjoying my evening there was something nagging at me, I realised that I should really write my session as I was due to give it the following morning. So after a few more drinks I headed back to the hotel and got some well earned sleep (and washed the fire damage out of my hair). Next day, headed off to the conference which was a lovely stroll through Glasgow City Centre. Non of us got mugged, murdered (or set on fire) arriving safely at the venue, which was a bonus.   I was asked to read out the opening Slides for Barry Carr's session which I did dilligently and with such professionalism that I shocked even myself. At which point I reliased in just over an hour I had to give my presentation, so headed back to the speaker room to finish writing it. Wham, bam and it was all over. Session seemed to go well. I was speaking on Exception Driven Development, which isn't so much a technical solution but rather a mindset around how one should treat exceptions and their code. To be honest, I've not been so nervous giving a session for years - something about this topic worried me, I was concerned I was being too abstract in my thinking or that what I was saying was so obvious that everyone would know it, but it seems to have been well recieved which makes me a happy Speaker. Craig Murphy has some brilliant pictures of DDD Scotland 2010. After my session was done I grabbed some lunch and headed back to the hotel and into town to do some shopping (thus my conspicuous omission from the above photo). Later on we headed out to the geek dinner which again was a rum affair followed by a few drinks and a little boogie woogie. All in all a well run, well attended conference, by the community for the community. I tip my hat to the whole team who put on DDD Scotland!       

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  • The WaitForAll Roadshow

    - by adweigert
    OK, so I took for granted some imaginative uses of WaitForAll but lacking that, here is how I am using. First, I have a nice little class called Parallel that allows me to spin together a list of tasks (actions) and then use WaitForAll, so here it is, WaitForAll's 15 minutes of fame ... First Parallel that allows me to spin together several Action delegates to execute, well in parallel.   public static class Parallel { public static ParallelQuery Task(Action action) { return new Action[] { action }.AsParallel(); } public static ParallelQuery> Task(Action action) { return new Action[] { action }.AsParallel(); } public static ParallelQuery Task(this ParallelQuery actions, Action action) { var list = new List(actions); list.Add(action); return list.AsParallel(); } public static ParallelQuery> Task(this ParallelQuery> actions, Action action) { var list = new List>(actions); list.Add(action); return list.AsParallel(); } }   Next, this is an example usage from an app I'm working on that just is rendering some basic computer information via WMI and performance counters. The WMI calls can be expensive given the distance and link speed of some of the computers it will be trying to communicate with. This is the actual MVC action from my controller to return the data for an individual computer.  public PartialViewResult Detail(string computerName) { var computer = this.Computers.Get(computerName); var perf = Factory.GetInstance(); var detail = new ComputerDetailViewModel() { Computer = computer }; try { var work = Parallel .Task(delegate { // Win32_ComputerSystem var key = computer.Name + "_Win32_ComputerSystem"; var system = this.Cache.Get(key); if (system == null) { using (var impersonation = computer.ImpersonateElevatedIdentity()) { system = computer.GetWmiContext().GetInstances().Single(); } this.Cache.Set(key, system); } detail.TotalMemory = system.TotalPhysicalMemory; detail.Manufacturer = system.Manufacturer; detail.Model = system.Model; detail.NumberOfProcessors = system.NumberOfProcessors; }) .Task(delegate { // Win32_OperatingSystem var key = computer.Name + "_Win32_OperatingSystem"; var os = this.Cache.Get(key); if (os == null) { using (var impersonation = computer.ImpersonateElevatedIdentity()) { os = computer.GetWmiContext().GetInstances().Single(); } this.Cache.Set(key, os); } detail.OperatingSystem = os.Caption; detail.OSVersion = os.Version; }) // Performance Counters .Task(delegate { using (var impersonation = computer.ImpersonateElevatedIdentity()) { detail.AvailableBytes = perf.GetSample(computer, "Memory", "Available Bytes"); } }) .Task(delegate { using (var impersonation = computer.ImpersonateElevatedIdentity()) { detail.TotalProcessorUtilization = perf.GetValue(computer, "Processor", "% Processor Time", "_Total"); } }).WithExecutionMode(ParallelExecutionMode.ForceParallelism); if (!work.WaitForAll(TimeSpan.FromSeconds(15), task => task())) { return PartialView("Timeout"); } } catch (Exception ex) { this.LogException(ex); return PartialView("Error.ascx"); } return PartialView(detail); }

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  • New Rapid Install StartCD 12.2.0.48 for EBS 12.2 Now Available

    - by Max Arderius
    A new Rapid Install startCD (Patch 18086193) for Oracle E-Business Suite Release 12.2 is now available. We recommend that all EBS customers installing or upgrading to EBS 12.2 use this latest update. The startCD updates are distributed to customers via My Oracle Support Patch which can be uncompressed on top of any previous 12.2 startCD under the main staging area. This patch replaces any previous startCDs. What's New in This Update? This new startCD version 12.2.0.48 includes important fixes for multi-node Installs, RAC, pre-install checks, platform specific issues, and upgrade scenario failures: 18703814 - QREP:122:RI:ISSUE WITH CHECKOS.CMD 18689527 - QREP:122:RI:ISSUE WITH FNDCORE.DLL SHIPPED AS PART OF R122 PACKAGE 18548485 - QREP1224:4:JAR SIGNER ISSUE DUE TO THE RI UPGRADE AUTOCONFIG CHANGES 18535812 - QREP:1220.48_4: 12.2.0 UPGRADE FILE SYSTEM LAY OUT IS AFFECTING THE DB TABLES 18507545 - WIN: UNABLE TO LAY DOWN FS PRIOR TO 12.2 UPGRADE WITHOUT AFFECTING RUNNING DB 18476041 - UNABLE TO LAY DOWN FS PRIOR TO 12.2 UPGRADE WITHOUT AFFECTING PRODUCTION DB 18459887 - R12.2 INSTALLATION FAILURE - OPMNCTL: NOT FOUND 18436053 - START CD 48_4 - ISSUES WITH TEMP SPACE CHECK 18424747 - QREP1224.3:ADD SERVER BROWSE BUTTON NOT WORKING 18421132 - *RW-50010: ERROR: - SCRIPT HAS RETURNED AN ERROR: 1 18403700 - QREP122.48:RI:UPGRADE RI PRECHECK HUNG IN SPLIT TIER APPS NODE ( NO SILENT ) 18383075 - ADD VERBOSE OPTION TO RAC VALIDATION 18363584 - UPTAKE INSTALL SCRIPTS FOR XB48_4 18336093 - QREP:122:RI:PATCH FS ADMIN SERVICE RUNNING AFTER RI UPGRADE CONFIGURE MODE 18320278 - QREP:1224.3:PLATFORM SPECIFIC SYNTAX ERRORS WITH DATE COMMAND IN DB CHECKER 18314643 - DISABLE SID=DB_NAME FOR RI UPGRADE FLOW IN RAC 18298977 - RI: EXCEPTION WHILE CLICKING RAC NODES BUTTON ON A NON-RAC SERVER 18286816 - QREP122:STARTCD48_3:TRAVERSING FROM VISION PASSW SCREEN TO PROD 18286371 - QREP122:STARTCD48_3:AMBIGUOUS MESSAGE DURING STAGE AREA CHECK ON HP 18275403 - QREP122:48:RI UPGRADE WITH EOH POST CHECKS HANGS IN SPLIT TIER DB NODE 18270631 - QREP122.48:MULTI-NODE RI USING NON-DEFAULT PASSWORDS NOT WORKING 18266046 - QREP122:48:RI NOT ALLOWING TO IGNORE THE RAC PRE-CHECK FAILURE 18242201 - UPTAKE TXK INSTALL SCRIPTS AND PLATFORMS.ZIP INTO STARTCD XB48_3 18236428 - QREP122.47:RI UPGRADE EXISTING OH FOR NON-DEFAULT APPS PASSWORD NOT WORKING 18220640 - INCONSISTENT DATABASE PORTS DURING EBS 12.2 INSTALLATION FOR STARTCD 12.2.0.47 18138796 - QREP122:47:RI 10.1.2 TECHSTACK NOT WORKING IF WE RUN RI FROM NEW STARTCD LOC 18138396 - TST1220: CONTROL FILE NAMING IN RAPID INSTALL SEEMS TO HAVE ISSUES 18124144 - IMPROVE HANDLING ERRORS FOUND IN CLUVFY LOG DURING PREINSTALL CHECKS 18111361 - VALIDATE ASM DB DATA FILES PATH AS +<DATA GROUP>/<PATH> 18102504 - QREP1220.47_5: UNZIP PANEL DOES NOT CREATE THE CORRECT STAGE 18083342 - 12.2 UPGRADE JAVA.NET.BINDEXCEPTION: CANNOT ASSIGN REQUESTED ADDRESS 18082140 - QREP122:47:RAC DB VALIDATION IS FAILS WITH EXIT STATUS IS 6 18062350 - 12.2.3 UPG: 12.2.0 INSTALLATION LOGS 18050840 - RI: UPGRADE WITH EXISTING RAC OH:SECONDARY DB NODE NAME IS BLANK 18049813 - RAC LOV DEFAULTS NOT SAVED UNLESS "SELECT" IS CLICKED 18003592 - TST1220:ADDITIONAL FREE SPACE CHECK FOR RI NEEDS TO BE CHECKED 17981471 - REMOVE ASM SPACE CHECK FROM RACVALIDATIONS.SH 17942179 - R12.2 INSTALL FAILING AT ADRUN11G.SH WITH ERRORS RW-50004 & RW-50010 17893583 - QREP1220.47:VALIDATION OF O.S IN RAPIDWIZ IN THE DB NODE CONFIGURATION SCREEN 17886258 - CLEANUP FND_NODES DURING UPGRADE FLOW 17858010 - RI POST INSTALL CHECKS (SSH VERIFICATION) STEP IS FAILING 17799807 - GEOHR: 12.2.0 - ERRORS IN RAPIDWIZ AND ADCONFIG LOGS 17786162 - QREP1223.4:RI:SERVICE_NAMES IS PRINTED AS SERVICE_NAME IN RI SCREEN 17782455 - RI: CONFIRM DEFAULT APPS PASSWORD IN SILENT MODE KICKOFF 17778130 - RI:ADMIN SERVER TO BE UP ON PRIMARY MID-TIER IN MULTI-NODE UPGRADE FS CREATION 17773989 - UN-SUPPORTED PLATFORM SHOWS 32 BIT AS HARD-CODED 17772655 - RELEVANT MESSAGE DURING THE RAPDIWIZ -TECHSTACK 17759279 - VERIFICATION PANEL DOES NOT EXPAND TECHNOLOGY STACK 17759183 - BUILDSTAGE SCRIPT MENU NEEDS TO BE ADJUSTED 17737186 - DATABASE PRE-REQ CHECK INCORRECTLY REPORTS SUCCESS ON AIX 17708082 - 12.2 INSTALLATION - OS PRE-REQUISITES CHECK 17701676 - TST122: GENERATE WRONG S_DBSID FOR PATCH FILE SYSTEM AT PHASE PREPARE 17630972 - /TMP PRE-REQ INSTALLATION CHECK 17617245 - 12.2 VISION INSTALL FAILS ON AIX 17603342 - OMCS: DB STAGING COMPLAINS WHILE MOVING IT TO FINAL LOCATION 17591171 - OMCS: DB STAGING FAILS WITH FRESH INSTALL R12.2 17588765 - CHECKER VERSION AND PLUGIN VERSION 17561747 - BUILDSTAGE.SH FAILS WITH ERROR WHEN STAGE HOSTED ON 32BIT LINUX 17539198 - RAPID INSTALL NEEDS TO IGNORE NON-REQUIRED STAGE ELEMENTS 17272808 - APPS USERS THAT HAVE DEFAULT PASSWORD AFTER 12.2 RAPID INSTALL References 12.2 Documentation Library 1581299.1 : EBS 12.2 Product Information Center 1320300.1 : Oracle E-Business Suite Release Notes, Release 12.2 1606170.1 : Oracle E-Business Suite Technology Stack and Applications DBA Release Notes for Release 12.2.3 1624423.1 : Oracle E-Business Suite Technology Stack and Applications DBA Release Notes for R12.TXK.C.Delta.4 and R12.AD.C.Delta.4 1594274.1 : Oracle E-Business Suite Release 12.2: Consolidated List of Patches and Technology Bug Fixes Related Articles Oracle E-Business Suite 12.2 Now Available startCD options to install Oracle E-Business Suite Release 12.2

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  • New features in TFS Demo Setup 1.0.0.2

    - by Tarun Arora
    Release Notes – http://tfsdemosetup.codeplex.com/ | Download | Source Code | Report a Bug | Ideas Just pushed out the 2nd release of the TFS Demo setup on CodePlex, below a quick look at some of the new features/improvements in the tool… Details of the existing features can be found here. Feature 1 – Set up Work Items Queries as Team Favorites The task board looks cooler when the team favourite work item queries show up on the task board. The demo setup console application now has the ability to set up the work item queries as team favorites for you. If you want to see how you can add Team Favorites programmatically, refer to this blogpost here. Image 1 – Task board without Team Favorites Let’s see how the TFS Demo Setup application sets-up team favorites as part of the run… Open up the DemoDictionary.xml and you should be able to see the new node <TeamFavorites> this accepts multiple <TeamFavorite>. You simply need to specify the <Type> as Query and in the <Name> specify the name of the work item query that you would like added as a favorite. Image 2 – Highlighting the TeamFavorites block in DemoDictionary.xml So, when the demo set up application is run with the above config, work item queries “Blocked Tasks” and “Open Impediments” are added as team favorites. They then show up on the task board, as highlighted in the screen shot below. Image 3 – Team Favorites setup during the TFS demo setup app execution Feature 2 – Choose what you want to setup and exclude the rest I had a great feature request come in requesting the ability to exclude parts of the setup at the sole discretion of the executioner. To accommodate this, I have added an attribute with each block, the attribute “Run” accepts “true” or “false”. If you set the flag to true then at the time of execution that block would be considered for setup and if you set the flag to false, the block will be ignored during the setup. So, lets look at an example below… The attribute "Run” is set to true for TeamSettings, Team Favorites, TeamMembers and WorkItems. So, all of these would be setup as part of the demo setup application execution. Image 4 – New Attribute Run added to all blocks in DemoDictionary.xml If I did not want to recreate the team and did not want to add new work items but only wanted to add favorites and team members to the existing team “AgileChamps1” then I could simple run the application with below DemoDictionary.xml. Note – TeamSettings Run=”false” and WorkItems Run=”false”. Image 5 – TeamFavorites and TeamMembers set as true and others set to false Feature 3 – Usability Improvement If you try and assign a work item to a team member that does not exist then the application throws a nasty exception. This behaviour has now been changed, upon adding such a work item, the work items will be created and not assigned to any user. The work item id will be printed to the console making it simple for you to assign the work item manually. As you can see in the screen shot below, I am trying to assign the work item to a user “Tarun” and a user “v2” both are *not valid users in my team project collection* so the tool creates the work items and provides me the work item id and lets me know that since the user is invalid the work item could not be assigned to the user. Better user experience ae Image 6 – Behaviour if work item assigned to users are in valid users in team project That’s about it for the current release. I have some new features planned for the next release. Mean while if you have any ideas/comments please feel free to leave a comment. Stay tuned for more… Enjoy! Other posts on TFS Demo Setup can be found here.

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  • How to Create SharePoint List and Insert List Item programmatically from a Windows Forms Application.

    - by Michael M. Bangoy
    In this post I’m going to demonstrate how to create SharePoint List and also Insert Items on the List from a Windows Forms Application. 1. Open Visual Studio and create a new project. On the project template select Windows Form Application under C#. 2. In order to communicate with Sharepoint from a Windows Forms Application we need to add the 2 Sharepoint Client DLL located in c:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\ISAPI.  3. Select the Microsoft.Sharepoint.Client.dll and Microsoft.Sharepoint.Client.Runtime.dll. (Your solution should look like the one below) 4. Open the Form1 in design view and from the Toolbox menu add a button on the form surface. Your form should look like the one below. 5. Double click the button to open the code view. Add Using statement to reference the Sharepoint Client Library then create method for the Create List. Your code should like the codes below. using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Security; using System.Windows.Forms; using SP = Microsoft.SharePoint.Client; namespace ClientObjectModel {     public partial class Form1 : Form     {         // url of the Sharepoint site         const string _context = "urlofthesharepointsite";         public Form1()         {             InitializeComponent();         }         private void Form1_Load(object sender, EventArgs e)         {                    }         private void cmdcreate_Click(object sender, EventArgs e)         {             try             {                 // declare the ClientContext Object                 SP.ClientContext _clientcontext = new SP.ClientContext(_context);                 SP.Web _site = _clientcontext.Web;                 // declare a ListCreationInfo                 SP.ListCreationInformation _listcreationinfo = new SP.ListCreationInformation();                 // set the Title and the Template of the List to be created                 _listcreationinfo.Title = "NewListFromCOM";                 _listcreationinfo.TemplateType = (int)SP.ListTemplateType.GenericList;                 // Call the add method to the ListCreatedInfo                 SP.List _list = _site.Lists.Add(_listcreationinfo);                 // Add Description field to the List                 SP.Field _Description = _list.Fields.AddFieldAsXml(@"                                     <Field Type='Text'                                         DisplayName='Description'>                                     </Field>", true, SP.AddFieldOptions.AddToDefaultContentType);                 // declare the List item Creation object for creating List Item                 SP.ListItemCreationInformation _itemcreationinfo = new SP.ListItemCreationInformation();                 // call the additem method of the list to insert a new List Item                 SP.ListItem _item = _list.AddItem(_itemcreationinfo);                 _item["Title"] = "New Item from Client Object Model";                 _item["Description"] = "This item was added by a Windows Forms Application";                 // call the update method                 _item.Update();                 // execute the query of the clientcontext                 _clientcontext.ExecuteQuery();                 // dispose the clientcontext                 _clientcontext.Dispose();                 MessageBox.Show("List Creation Successfull");             }             catch(Exception ex)             {                 MessageBox.Show("Error creating list" + ex.ToString());             }          }     } } 6. Hit F5 to run the application. A message will be displayed on the screen if the operation is successful and also if it fails. 7. To make that the operation of our Windows Form Application has really created the List and Inserted an item on it. Let’s open our SharePoint site. Once the SharePoint is open click on the Site Actions then View All Site Content. 7. Click the List to open it and check if an Item is inserted. That’s it. Hope this helps.

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  • Tyrus 1.8

    - by Pavel Bucek
    Another version of Tyrus, the reference implementation of JSR 356 – Java API for WebSocket is out! Complete list of fixes and features is below, but let me describe some of the new features in more detail. All information presented here is also available in Tyrusdocumentation. What’s new? First to mention is that JSR 356 Maintenance review Ballot is over and the change proposed for 1.1 release was accepted. More details about changes in the API can be found in this article. Important part is that Tyrus 1.8 implements this API, meaning you can use Lambda expressions and some features of Nashorn without the need for any workarounds. Almost all other features are related to client side support, which was significantly improved in this release. Firstly – I have to admit, that Tyrus client contained security issue – SSL Hostname verification was not performed when connecting to “wss” endpoints. This was fixed as part of TYRUS-339 and resulted in some changes in the client configuration API. Now you can control whether HostnameVerification should be performed (SslEngineConfigurator#setHostnameVerificationEnabled(boolean)) or even set your own HostnameVerifier (please use carefully): #setHostnameVerifier(…). Detailed description can be found in Host verification chapter. Another related enhancement is support for Http Basic and Digest authentication schemes. Tyrus client now enables users to provide credentials and underlying implementation will take care of everything else. Our implementation is strictly non pre-emptive, so the login information is sent always as a response to 401 Http Status Code. If the Basic and Digest are not good enough and there is a need to use some custom scheme or something which is not yet supported in Tyrus, custom Authenticator can be registered and the authentication part of the handshake process will be handled by it. Please seeClient HTTP Authentication chapter in the user guide for more details. There are other features, like fine-grain threadpool configuration for JDK client container, build-in Http redirect support and some reshuffling related to unifying the location of client configuration classes and properties definition – every property should be now part of ClientProperties class. All new features are described in the user guide – in chapterTyrus proprietary configuration. Update – Tyrus 1.8.1 There was another slightly late reported issue related to running in environments with SecurityManager enabled, so this version fixes that. Another noteworthy fixes are TYRUS-355 and TYRUS-361; the first one is about incorrect thread factory used for shared container timeout, which resulted in JVM waiting for that thread and not exiting as it should. The other issue enables relative URIs in Location header when using redirect feature. Links Tyrus homepage mailing list JIRA Complete list of changes: Bug [TYRUS-333] – Multiple endpoints on one client [TYRUS-334] – When connection is closed by a peer, periodic heartbeat pong is not stopped [TYRUS-336] – ReaderBuffer.getNextChars() keeps blocking a server thread after client has closed the session [TYRUS-338] – JDK client SSL filter needs better synchronization during handshake phase [TYRUS-339] – SSL hostname verification is missing [TYRUS-340] – Test PathParamTest are not stable with JDK client [TYRUS-341] – A control frame inside a stream of continuation frames is treated as the part of the stream [TYRUS-343] – ControlFrameInDataStreamTest does not pass on GF [TYRUS-345] – NPE is thrown, when shared container timeout property in JDK client is not set [TYRUS-346] – IllegalStateException is thrown, when using proxy in JDK client [TYRUS-347] – Introduce better synchronization in JDK client thread pool [TYRUS-348] – When a client and server close connection simultaneously, JDK client throws NPE [TYRUS-356] – Tyrus cannot determine the connection port for a wss URL [TYRUS-357] – Exception thrown in MessageHandler#OnMessage is not caught in @OnError method [TYRUS-359] – Client based on Java 7 Asynchronous IO makes application unexitable Improvement [TYRUS-328] – JDK 1.7 AIO Client container – threads – (setting threadpool, limits, …) [TYRUS-332] – Consolidate shared client properties into one file. [TYRUS-337] – Create an SSL version of Basic Servlet test New Feature [TYRUS-228] – Add client support for HTTP Basic/Digest Task [TYRUS-330] – create/run tests/servlet/basic via wss [TYRUS-335] – [clustering] – introduce RemoteSession and expose them via separate method (not include remote sessions in the getOpenSessions()) [TYRUS-344] – Introduce Client support for HTTP Redirect

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  • Taking a screenshot from within a Silverlight #WP7 application

    - by Laurent Bugnion
    Often times, you want to take a screenshot of an application’s page. There can be multiple reasons. For instance, you can use this to provide an easy feedback method to beta testers. I find this super invaluable when working on integration of design in an app, and the user can take quick screenshots, attach them to an email and send them to me directly from the Windows Phone device. However, the same mechanism can also be used to provide screenshots are a feature of the app, for example if the user wants to save the current status of his application, etc. Caveats Note the following: The code requires an XNA library to save the picture to the media library. To have this, follow the steps: In your application (or class library), add a reference to Microsoft.Xna.Framework. In your code, add a “using” statement to Microsoft.Xna.Framework.Media. In the Properties folder, open WMAppManifest.xml and add the following capability: ID_CAP_MEDIALIB. The method call will fail with an exception if the device is connected to the Zune application on the PC. To avoid this, either disconnect the device when testing, or end the Zune application on the PC. While the method call will not fail on the emulator, there is no way to access the media library, so it is pretty much useless on this platform. This method only prints Silverlight elements to the output image. Other elements (such as a WebBrowser control’s content for instance) will output a black rectangle. The code public static void SaveToMediaLibrary( FrameworkElement element, string title) { try { var bmp = new WriteableBitmap(element, null); var ms = new MemoryStream(); bmp.SaveJpeg( ms, (int)element.ActualWidth, (int)element.ActualHeight, 0, 100); ms.Seek(0, SeekOrigin.Begin); var lib = new MediaLibrary(); var filePath = string.Format(title + ".jpg"); lib.SavePicture(filePath, ms); MessageBox.Show( "Saved in your media library!", "Done", MessageBoxButton.OK); } catch { MessageBox.Show( "There was an error. Please disconnect your phone from the computer before saving.", "Cannot save", MessageBoxButton.OK); } } This method can save any FrameworkElement. Typically I use it to save a whole page, but you can pass any other element to it. On line 7, we create a new WriteableBitmap. This excellent class can render a visual tree into a bitmap. Note that for even more features, you can use the great WriteableBitmapEx class library (which is open source). On lines 9 to 16, we save the WriteableBitmap to a MemoryStream. The only format supported by default is JPEG, however it is possible to convert to other formats with the ImageTools library (also open source). Lines 18 to 20 save the picture to the Windows Phone device’s media library. Using the image To retrieve the image, simply launch the Pictures library on the phone. The image will be in Saved Pictures. From here, you can share the image (by email, for instance), or synchronize it with the PC using the Zune software. Saving to other platforms It is of course possible to save to other platforms than the media library. For example, you can send the image to a web service, or save it to the isolated storage on the device. To do this, instead of using a MemoryStream, you can use any other stream (such as a web request stream, or a file stream) and save to that instead. Hopefully this code will be helpful to you! Happy coding, Laurent   Laurent Bugnion (GalaSoft) Subscribe | Twitter | Facebook | Flickr | LinkedIn

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  • Building on someone else's DefaultButton Silverlight work...

    - by KyleBurns
    This week I was handed a "simple" requirement - have a search screen execute its search when the user pressed the Enter key instead of having to move hands from keyboard to mouse and click Search.  That is a reasonable request that has been met for years both in Windows and Web apps.  I did a quick scan for code to pilfer and found Patrick Cauldwell's Blog posting "A 'Default Button' In Silverlight".  This posting was a great start and I'm glad that the basic work had been done for me, but I ran into one issue - when using bound textboxes (I'm a die-hard MVVM enthusiast when it comes to Silverlight development), the search was being executed before the textbox I was in when the Enter key was pressed updated its bindings.  With a little bit of reflection work, I think I have found a good generic solution that builds upon Patrick's to make it more binding-friendly.  Also, I wanted to set the DefaultButton at a higher level than on each TextBox (or other control for that matter), so the use of mine is intended to be set somewhere such as the LayoutRoot or other high level control and will apply to all controls beneath it in the control tree.  I haven't tested this on controls that treat the Enter key special themselves in the mix. The real change from Patrick's solution here is that in the KeyUp event, I grab the source of the KeyUp event (in my case the textbox containing search criteria) and loop through the static fields on the element's type looking for DependencyProperty instances.  When I find a DependencyProperty, I grab the value and query for bindings.  Each time I find a binding, UpdateSource is called to make sure anything bound to any property of the field has the opportunity to update before the action represented by the DefaultButton is executed. Here's the code: public class DefaultButtonService { public static DependencyProperty DefaultButtonProperty = DependencyProperty.RegisterAttached("DefaultButton", typeof (Button), typeof (DefaultButtonService), new PropertyMetadata (null, DefaultButtonChanged)); private static void DefaultButtonChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { var uiElement = d as UIElement; var button = e.NewValue as Button; if (uiElement != null && button != null) { uiElement.KeyUp += (sender, arg) => { if (arg.Key == Key.Enter) { var element = arg.OriginalSource as FrameworkElement; if (element != null) { UpdateBindings(element); } if (button.IsEnabled) { button.Focus(); var peer = new ButtonAutomationPeer(button); var invokeProv = peer.GetPattern(PatternInterface.Invoke) as IInvokeProvider; if (invokeProv != null) invokeProv.Invoke(); arg.Handled = true; } } }; } } public static DefaultButtonService GetDefaultButton(UIElement obj) { return (DefaultButtonService) obj.GetValue(DefaultButtonProperty); } public static void SetDefaultButton(DependencyObject obj, DefaultButtonService button) { obj.SetValue(DefaultButtonProperty, button); } public static void UpdateBindings(FrameworkElement element) { element.GetType().GetFields(BindingFlags.Public | BindingFlags.Static).ForEach(field => { if (field.FieldType.IsAssignableFrom(typeof(DependencyProperty))) { try { var dp = field.GetValue(null) as DependencyProperty; if (dp != null) { var binding = element.GetBindingExpression(dp); if (binding != null) { binding.UpdateSource(); } } } // ReSharper disable EmptyGeneralCatchClause catch (Exception) // ReSharper restore EmptyGeneralCatchClause { // swallow exceptions } } }); } }

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  • Session and Pop Up Window

    - by imran_ku07
     Introduction :        Session is the secure state management. It allows the user to store their information in one page and access in another page. Also it is so much powerful that store any type of object. Every user's session is identified by their cookie, which client presents to server. But unfortunately when you open a new pop up window, this cookie is not post to server with request, due to which server is unable to identify the session data for current user.         In this Article i will show you how to handle this situation,  Description :         During working in a application, i was getting an Exception saying that Session is null, when a pop window opens. After seeing the problem more closely i found that ASP.NET_SessionId cookie for parent page is not post in cookie header of child (popup) window.         Therefore for making session present in both parent and child (popup) window, you have to present same cookie. For cookie sharing i passed parent SessionID in query string,   window.open('http://abc.com/s.aspx?SASID=" & Session.SessionID &','V');           and in Application_PostMapRequestHandler application Event, check if the current request has no ASP.NET_SessionId cookie and SASID query string is not null then add this cookie to Request before Session is acquired, so that Session data remain same for both parent and popup window.    Private Sub Application_PostMapRequestHandler(ByVal sender As Object, ByVal e As EventArgs)           If (Request.Cookies("ASP.NET_SessionId") Is Nothing) AndAlso (Request.QueryString("SASID") IsNot Nothing) Then               Request.Cookies.Add(New HttpCookie("ASP.NET_SessionId", Request.QueryString("SASID")))           End If       End Sub           Now access Session in your parent and child window without any problem. How this works :          ASP.NET (both Web Form or MVC) uses a cookie (ASP.NET_SessionId) to identify the user who is requesting. Cookies are may be persistent (saved permanently in user cookies ) or non-persistent (saved temporary in browser memory). ASP.NET_SessionId cookie saved as non-persistent. This means that if the user closes the browser, the cookie is immediately removed. This is a sensible step that ensures security. That's why ASP.NET unable to identify that the request is coming from the same user. Therefore every browser instance get it's own ASP.NET_SessionId. To resolve this you need to present the same parent ASP.NET_SessionId cookie to the server when open a popup window.           You can confirm this situation by using some tools like Firebug, Fiddler,  Summary :          Hopefully you will enjoy after reading this article, by seeing that how to workaround the problem of sharing Session between different browser instances by sharing their Session identifier Cookie.

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  • PASS: International Travels

    - by Bill Graziano
    Nihao!  One of the largest changes PASS is going through is the the expansion outside the US and Canada.  We’ve had international chapters and events in Europe since the early 2000’s.  But nothing on the scale we’re seeing now.  Since January 1st there have been 18 SQL Saturday events outside North America and 19 events in North America.  We hope to have three international SQLRally events outside the US in FY13 (budget willing).  I don’t know the exact percentage of chapters outside the US but it’s got be 50% or higher. We recently started an effort to remake the Board to better reflect the growing global face of PASS.  This involves assigning some Board seats to geographic regions.  You can ask questions about this in our feedback forum, participate in a Twitter chat or ask questions directly of Board members.  You can email me at if you’d like to ask a question directly.  We’re doing this very slowly and deliberately in hopes that a long communication cycle gives us a chance to address all the issues that our members will raise. After the Summit we passed a budget exception allocating an extra $20,000 for Board members to travel to local events.  I think it’s important for Board members to visit new areas and talk to more of our members.  I sent out an email asking where people had attended events outside their home city.  Here’s the list I got back: Albuquerque, Amsterdam, Boston, Brisbane, Chicago, Colorado Springs, Columbus, Dallas, Houston, Jacksonville, Las Vegas, London, Louisville, Minneapolis, New York City, Orange County, Orlando, Pensacola, Perth, Philadelphia, Phoenix, Redmond, Seattle, Silicon Valley, Sydney, Tampa Bay, Vancouver, Washington DC and Wellington.  (Disclaimer: Some of this travel was paid for by employers or Board members themselves.  Some of this travel may have been completed before the Summit.  That’s still one heck of a list!) The last SQL Saturday event this fiscal year is SQL Saturday Shanghai.  And that’s one I’m attending.  This is our first event in China and is being put on in cooperation with the local Microsoft office.  Hopefully this event will be the start of a growing community in China that includes chapters, SQL Saturdays and maybe a SQLRally or two in the future.  I’m excited to speak with people that are just starting down this path and watching this community grow. I encourage you to visit the PASS Global Growth site and read through the material there.  This is the biggest change we’ve made to our governance since I’ve been on the Board.  You need to understand how it affects you and how it affects the organization. And wish me luck on the 15 hour flight to Shanghai on Friday afternoon.  Rob Farley flies from Australia to the US for PASS events multiple times per year and I don’t know how he does it so often.  I think one of these is going to wipe me out.  (And Nihao (knee-how) is Chinese for Hello.)

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  • Question on the implementation of my Entity System

    - by miguel.martin
    I am currently creating an Entity System, in C++, it is almost completed (I have all the code there, I just have to add a few things and test it). The only thing is, I can't figure out how to implement some features. This Entity System is based off a bit from the Artemis framework, however it is different. I'm not sure if I'll be able to type this out the way my head processing it. I'm going to basically ask whether I should do something over something else. Okay, now I'll give a little detail on my Entity System itself. Here are the basic classes that my Entity System uses to actually work: Entity - An Id (and some methods to add/remove/get/etc Components) Component - An empty abstract class ComponentManager - Manages ALL components for ALL entities within a Scene EntitySystem - Processes entities with specific components Aspect - The class that is used to help determine what Components an Entity must contain so a specific EntitySystem can process it EntitySystemManager - Manages all EntitySystems within a Scene EntityManager - Manages entities (i.e. holds all Entities, used to determine whether an Entity has been changed, enables/disables them, etc.) EntityFactory - Creates (and destroys) entities and assigns an ID to them Scene - Contains an EntityManager, EntityFactory, EntitySystemManager and ComponentManager. Has functions to update and initialise the scene. Now in order for an EntitySystem to efficiently know when to check if an Entity is valid for processing (so I can add it to a specific EntitySystem), it must recieve a message from the EntityManager (after a call of activate(Entity& e)). Similarly the EntityManager must know when an Entity is destroyed from the EntityFactory in the Scene, and also the ComponentManager must know when an Entity is created AND destroyed. I do have a Listener/Observer pattern implemented at the moment, but with this pattern I may remove a Listener (which is this case is dependent on the method being called). I mainly have this implemented for specific things related to a game, i.e. Teams, Tagging of entities, etc. So... I was thinking maybe I should call a private method (using friend classes) to send out when an Entity has been activated, deleted, etc. i.e. taken from my EntityFactory void EntityFactory::killEntity(Entity& e) { // if the entity doesn't exsist in the entity manager within the scene if(!getScene()->getEntityManager().doesExsist(e)) { return; // go back to the caller! (should throw an exception or something..) } // tell the ComponentManager and the EntityManager that we killed an Entity getScene()->getComponentManager().doOnEntityWillDie(e); getScene()->getEntityManager().doOnEntityWillDie(e); // notify the listners for(Mouth::iterator i = getMouth().begin(); i != getMouth().end(); ++i) { (*i)->onEntityWillDie(*this, e); } _idPool.addId(e.getId()); // add the ID to the pool delete &e; // delete the entity } As you can see on the lines where I am telling the ComponentManager and the EntityManager that an Entity will die, I am calling a method to make sure it handles it appropriately. Now I realise I could do this without calling it explicitly, with the help of that for loop notifying all listener objects connected to the EntityFactory's Mouth (an object used to tell listeners that there's an event), however is this a good idea (good design, or what)? I've gone over the PROS and CONS, I just can't decide what I want to do. Calling Explicitly: PROS Faster? Since these functions are explicitly called, they can't be "removed" CONS Not flexible Bad design? (friend functions) Calling through Listener objects (i.e. ComponentManager/EntityManager inherits from a EntityFactoryListener) PROS More Flexible? Better Design? CONS Slower? (virtual functions) Listeners can be removed, i.e. may be removed and not get called again during the program, which could cause in a crash. P.S. If you wish to view my current source code, I am hosting it on BitBucket.

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  • Administer, manage, monitor, and fine tune the performance of your Oracle SOA Suite 11g Service Infrastructure and SOA composite applications.

    - by JuergenKress
    Key Features of the book If you are an Oracle SOA suite administrator, then this book is your bible. It gives you everything you need to know about all your tasks and help you to apply what you learn in your everyday life right from the first chapter. The book walks through promoting code across environments, performance tuning the service infrastructure, monitoring the environment, configuring security policies, managing the dehydration store, backing and restoring environments and so on. Packed with real-world examples from authors' own experiences, this books offers a unique insight into Oracle SOA Suite Administration. Detailed description The book begins with an introduction of SOA and quickly moves on to management of SOA composite applications. Readers will learn how to manage composite applications, their deployments and lifecycles. Equipped with this knowledge, readers will be introduced to monitoring and performance tuning SOA Suite, monitoring instances, messages, and composite applications, managing faults and exceptions, configuring audit levels of composite applications to include end-to-end monitoring through the use of extended logging as well as administering and configuring all SOA Suite components. A very important aspect of administration is tuning and optimizing the infrastructure for performance and book offers real work recommendations to monitor and performance tune service engines, the underlying WebLogic server, threads and timeouts, files systems, and composite applications. It also covers detailed administration of individual service components, configuring the infrastructure MBeans using both Oracle Enterprise Manager Fusion Middleware Control and WLST based scripts, migrating worklist preferences and BAM data across environments, setting up Email, LDAP and custom XPath. An administrator is always trusted with troubleshooting and root causing problems in the infrastructure and this book will help you through the troubleshooting approaches as how to identify faults and exception through extended logging and thread dumps and find solutions to common startup problems and deployment issues. The advanced contents of this book explains OWSM security framework and how to secure components deployed to the infrastructure along with the details of all groundwork needed to ready the environment. Last few chapters help you to understand and deal with managing the metadata services repository and dehydration store, backup and recovery and concluding with advanced topics such as silent/scripted installations, cloning, upgrading, patching and high availability installations. Packed with real-world examples, and tips straight from the trench; this book offers insights into SOA Suite administration that you will not find elsewhere. Part of our writing style in this book draws heavily on the philosophy of reuse and as such the book provide an ample of executable SQL queries and WLST scripts that administrators can reuse and extend to perform most of the administration tasks such as monitoring instances, processing times, instance states and perform automatic deployments, tuning, migration, and installation. These scripts are spread over each of the chapters in the book and can also be downloaded from here. The book is available in different formats at the following websites: Paperback and eBook versions & Kindle version. It is available for order and signed copies are available through our web site. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit  www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Mix Forum Technorati Tags: SOA book,SOA Suite Adminsitration,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

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  • Application Module Extension in Oracle Application R12

    - by Manoj Madhusoodanan
    In this blog I will describe how to Extend Application Module.I will explain this based on my previous blog PL/SQL based EO.  I want to extend FndUserAM to add a procedure to raise a custom business event when the FND_USER has created successfully. Here I am using a custom business event "xxcust.oracle.apps.demo_event". Please find the code used in Business Event. TablePackage Following steps needs to perform. 1) Download all files pertaining to "Entity Object Based on PL/SQL" to JDEV_USER_HOME/myprojects and JDEV_USER_HOME/myclasses.If you want to see the content of source java file decompile it and save it in JDEV_USER_HOME/myprojects. 2) Create XXFndUserAM as follows. 3) Add following method to XXFndUserAMImpl.    import oracle.apps.fnd.framework.OAException;   import oracle.apps.fnd.framework.server.OADBTransactionImpl;   import oracle.apps.fnd.wf.bes.BusinessEvent;   import oracle.apps.fnd.wf.bes.BusinessEventException;    import java.sql.Connection;     public void raiseEvent(String userName) {        String eventName = "xxcust.oracle.apps.demo_event";        String eventKey = userName;        Connection conn = ((OADBTransactionImpl)getOADBTransaction()).getJdbcConnection();         BusinessEvent event = null;         try{             event = new BusinessEvent(eventName, eventKey);             /* Setting Parameters */             event.setStringProperty("USER_NAME",userName);             event.setStringProperty("STATUS","User has created sucessfully");             event.raise(conn);             }             catch (BusinessEventException e) {                 throw new OAException("Exception occured when invoking web service - "+e.getMessage());             }             getOADBTransaction().commit();    } 4) Create a controller which extends from xxcust.oracle.apps.fnd.user.webui.CreateFndUserCO.Call raiseEvent method from new controller. 5) Create substitution for FndUserAM. 6) Migrate following files to $JAVA_TOP. xxcustom.oracle.apps.fnd.user.server.FndUserAMImpl.javaxxcustom.oracle.apps.fnd.user.server.XXFndUserAM.xmlxxcustom.oracle.apps.fnd.user.webui.XXCreateFndUserCO.java 8) Migrate the substitution. 9) Restart the server. 10) Personalize the page /xxcust/oracle/apps/fnd/user/webuiCreateFndUserPG and set the new controller. 11) Verify the substitution has properly applied by clicking About the Page. 12) Access the page and create a user. You can the the result of the Business Event.

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  • Oracle GoldenGate Active-Active Part 1

    - by Nick_W
    My name is Nick Wagner, and I'm a recent addition to the Oracle Maximum Availability Architecture (MAA) product management team.  I've spent the last 15+ years working on database replication products, and I've spent the last 10 years working on the Oracle GoldenGate product.  So most of my posting will probably be focused on OGG.  One question that comes up all the time is around active-active replication with Oracle GoldenGate.  How do I know if my application is a good fit for active-active replication with GoldenGate?   To answer that, it really comes down to how you plan on handling conflict resolution.  I will delve into topology and deployment in a later blog, but here is a simple architecture: The two most common resolution routines are host based resolution and timestamp based resolution. Host based resolution is used less often, but works with the fewest application changes.  Think of it like this: any transactions from SystemA always take precedence over any transactions from SystemB.  If there is a conflict on SystemB, then the record from SystemA will overwrite it.  If there is a conflict on SystemA, then it will be ignored.  It is quite a bit less restrictive, and in most cases, as long as all the tables have primary keys, host based resolution will work just fine.  Timestamp based resolution, on the other hand, is a little trickier. In this case, you can decide which record is overwritten based on timestamps. For example, does the older record get overwritten with the newer record?  Or vice-versa?  This method not only requires primary keys on every table, but it also requires every table to have a timestamp/date column that is updated each time a record is inserted or updated on the table.  Most homegrown applications can always be customized to include these requirements, but it's a little more difficult with 3rd party applications, and might even be impossible for large ERP type applications.  If your database has these features - whether it’s primary keys for host based resolution, or primary keys and timestamp columns for timestamp based resolution - then your application could be a great candidate for active-active replication.  But table structure is not the only requirement.  The other consideration applies when there is a conflict; i.e., do I need to perform any notification or track down the user that had their data overwritten?  In most cases, I don't think it's necessary, but if it is required, OGG can always create an exceptions table that contains all of the overwritten transactions so that people can be notified. It's a bit of extra work to implement this type of option, but if the business requires it, then it can be done. Unless someone is constantly monitoring this exception table or has an automated process in dealing with exceptions, there will be a delay in getting a response back to the end user. Ideally, when setting up active-active resolution we can include some simple procedural steps or configuration options that can reduce, or in some cases eliminate the potential for conflicts.  This makes the whole implementation that much easier and foolproof.  And I'll cover these in my next blog. 

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  • Dynamically load and call delegates based on source data

    - by makerofthings7
    Assume I have a stream of records that need to have some computation. Records will have a combination of these functions run Sum, Aggregate, Sum over the last 90 seconds, or ignore. A data record looks like this: Date;Data;ID Question Assuming that ID is an int of some kind, and that int corresponds to a matrix of some delegates to run, how should I use C# to dynamically build that launch map? I'm sure this idea exists... it is used in Windows Forms which has many delegates/events, most of which will never actually be invoked in a real application. The sample below includes a few delegates I want to run (sum, count, and print) but I don't know how to make the quantity of delegates fire based on the source data. (say print the evens, and sum the odds in this sample) using System; using System.Threading; using System.Collections.Generic; internal static class TestThreadpool { delegate int TestDelegate(int parameter); private static void Main() { try { // this approach works is void is returned. //ThreadPool.QueueUserWorkItem(new WaitCallback(PrintOut), "Hello"); int c = 0; int w = 0; ThreadPool.GetMaxThreads(out w, out c); bool rrr =ThreadPool.SetMinThreads(w, c); Console.WriteLine(rrr); // perhaps the above needs time to set up6 Thread.Sleep(1000); DateTime ttt = DateTime.UtcNow; TestDelegate d = new TestDelegate(PrintOut); List<IAsyncResult> arDict = new List<IAsyncResult>(); int count = 1000000; for (int i = 0; i < count; i++) { IAsyncResult ar = d.BeginInvoke(i, new AsyncCallback(Callback), d); arDict.Add(ar); } for (int i = 0; i < count; i++) { int result = d.EndInvoke(arDict[i]); } // Give the callback time to execute - otherwise the app // may terminate before it is called //Thread.Sleep(1000); var res = DateTime.UtcNow - ttt; Console.WriteLine("Main program done----- Total time --> " + res.TotalMilliseconds); } catch (Exception e) { Console.WriteLine(e); } Console.ReadKey(true); } static int PrintOut(int parameter) { // Console.WriteLine(Thread.CurrentThread.ManagedThreadId + " Delegate PRINTOUT waited and printed this:"+parameter); var tmp = parameter * parameter; return tmp; } static int Sum(int parameter) { Thread.Sleep(5000); // Pretend to do some math... maybe save a summary to disk on a separate thread return parameter; } static int Count(int parameter) { Thread.Sleep(5000); // Pretend to do some math... maybe save a summary to disk on a separate thread return parameter; } static void Callback(IAsyncResult ar) { TestDelegate d = (TestDelegate)ar.AsyncState; //Console.WriteLine("Callback is delayed and returned") ;//d.EndInvoke(ar)); } }

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  • Is there a theory for "transactional" sequences of failing and no-fail actions?

    - by Ross Bencina
    My question is about writing transaction-like functions that execute sequences of actions, some of which may fail. It is related to the general C++ principle "destructors can't throw," no-fail property, and maybe also with multi-phase transactions or exception safety. However, I'm thinking about it in language-neutral terms. My concern is with correctly designing error handling in C++ functions that must be reliable. I would like to know what the concepts below are called so that I can learn more about them. I'm sorry that I can't ask the question more directly. Since I don't know this area I have provided an example to explain my question. The question is at the end. Here goes: Consider a sequence of steps or actions executed sequentially, where actions belong to one of two classes: those that always succeed, and those that may fail. In the examples below: S stands for an action that always succeeds (called "no-fail" in some settings). F stands for an action that may fail (for example, it might fail to allocate memory or do I/O that could fail). Consider a sequences of actions (executed sequentially from left to right): S->S->S->S Since each action in the sequence above succeeds, the whole sequence succeeds. On the other hand, the following sequence may fail because the last action may fail: S->S->S->F So, claim: a sequence has the no-fail (S) property if and only if all of its actions are no-fail. Now, I'm interested in action sequences that form "atomic transactions", with "failure atomicity," i.e. where either the whole sequence completes successfully, or there is no effect. I.e. if some action fails, the earlier ones must be rolled back. This requires that any successfully executed actions prior to a failing action must always be able to be rolled back. Consider the sequence: S->S->S->F S<-S<-S In the example above, the first row is the forward path of the transaction, and the second row are inverse actions (executed from right to left) that can be used to roll back if the final top row actions fails. It seems to me that for a transaction to support failure atomicity, the following invariant must hold: Claim: To support failure atomicity (either completion or complete roll-back on failure) all actions preceding the latest failable (F) action on the forward path (marked * in the example below) must have no-fail (S) inverses. The following is an example of a sequence that supports failure atomicity: * S->F->F->F S<-S<-S Further, if we want the transaction to be able to attempt cancellation mid-way through, but still guarantee either full completion or full rollback then we need the following property: Claim: To support failure atomicity and cancellation mid-way through execution, in the face of errors in the inverse (cancellation) path, all actions following the earliest failable (F) inverse on the reverse path (marked *) must be no-fail (S). F->F->F->S->S S<-S<-F<-F * I believe that these two conditions guarantee that an abortable/cancelable transaction will never get "stuck". My questions are: What is the study and theory of these properties called? are my claims correct? and what else is there to know? UPDATE 1: Updated terminology: what I previously called "robustness" is called atomicity in the database literature. UPDATE 2: Added explicit reference to failure atomicity, which seems to be a thing.

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  • JOGL2 test compiles, but doesn't execute - help?

    - by Chuchinyi
    I have a problem with JOGL2. My JOGL2Template.java compiles fine, but executing it results in the following error: D:\java\java\jogl>javac JOGL2Template.java <== compile ok D:\java\java\jogl>java JOGL2Template <== execute error Exception in thread "main" java.lang.ExceptionInInitializerError at javax.media.opengl.GLProfile.<clinit>(GLProfile.java:1176) at JOGL2Template.<init>(JOGL2Template.java:24) at JOGL2Template.main(JOGL2Template.java:57) Caused by: java.lang.SecurityException: no certificate for gluegen-rt.dll in D:\ java\lib\gluegen-rt-natives-windows-i586.jar at com.jogamp.common.util.JarUtil.validateCertificate(JarUtil.java:350) at com.jogamp.common.util.JarUtil.validateCertificates(JarUtil.java:324) at com.jogamp.common.util.cache.TempJarCache.validateCertificates(TempJa rCache.java:328) at com.jogamp.common.util.cache.TempJarCache.bootstrapNativeLib(TempJarC ache.java:283) at com.jogamp.common.os.Platform$3.run(Platform.java:308) at java.security.AccessController.doPrivileged(Native Method) at com.jogamp.common.os.Platform.loadGlueGenRTImpl(Platform.java:298) at com.jogamp.common.os.Platform.<clinit>(Platform.java:207) ... 3 more Here is the JOGL2Template.java source code: import java.awt.Dimension; import java.awt.Frame; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import javax.media.opengl.GLAutoDrawable; import javax.media.opengl.GLCapabilities; import javax.media.opengl.GLEventListener; import javax.media.opengl.GLProfile; import javax.media.opengl.awt.GLCanvas; import com.jogamp.opengl.util.FPSAnimator; import javax.swing.JFrame; /* * JOGL 2.0 Program Template For AWT applications */ public class JOGL2Template extends JFrame implements GLEventListener { private static final int CANVAS_WIDTH = 640; // Width of the drawable private static final int CANVAS_HEIGHT = 480; // Height of the drawable private static final int FPS = 60; // Animator's target frames per second // Constructor to create profile, caps, drawable, animator, and initialize Frame public JOGL2Template() { // Get the default OpenGL profile that best reflect your running platform. GLProfile glp = GLProfile.getDefault(); // Specifies a set of OpenGL capabilities, based on your profile. GLCapabilities caps = new GLCapabilities(glp); // Allocate a GLDrawable, based on your OpenGL capabilities. GLCanvas canvas = new GLCanvas(caps); canvas.setPreferredSize(new Dimension(CANVAS_WIDTH, CANVAS_HEIGHT)); canvas.addGLEventListener(this); // Create a animator that drives canvas' display() at 60 fps. final FPSAnimator animator = new FPSAnimator(canvas, FPS); addWindowListener(new WindowAdapter() { // For the close button @Override public void windowClosing(WindowEvent e) { // Use a dedicate thread to run the stop() to ensure that the // animator stops before program exits. new Thread() { @Override public void run() { animator.stop(); System.exit(0); } }.start(); } }); add(canvas); pack(); setTitle("OpenGL 2 Test"); setVisible(true); animator.start(); // Start the animator } public static void main(String[] args) { new JOGL2Template(); } @Override public void init(GLAutoDrawable drawable) { // Your OpenGL codes to perform one-time initialization tasks // such as setting up of lights and display lists. } @Override public void display(GLAutoDrawable drawable) { // Your OpenGL graphic rendering codes for each refresh. } @Override public void reshape(GLAutoDrawable drawable, int x, int y, int w, int h) { // Your OpenGL codes to set up the view port, projection mode and view volume. } @Override public void dispose(GLAutoDrawable drawable) { // Hardly used. } } Any ideas what might be the cause of these errors?

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  • Learn Many Languages

    - by Jeff Foster
    My previous blog, Deliberate Practice, discussed the need for developers to “sharpen their pencil” continually, by setting aside time to learn how to tackle problems in different ways. However, the Sapir-Whorf hypothesis, a contested and somewhat-controversial concept from language theory, seems to hold reasonably true when applied to programming languages. It states that: “The structure of a language affects the ways in which its speakers conceptualize their world.” If you’re constrained by a single programming language, the one that dominates your day job, then you only have the tools of that language at your disposal to think about and solve a problem. For example, if you’ve only ever worked with Java, you would never think of passing a function to a method. A good developer needs to learn many languages. You may never deploy them in production, you may never ship code with them, but by learning a new language, you’ll have new ideas that will transfer to your current “day-job” language. With the abundant choices in programming languages, how does one choose which to learn? Alan Perlis sums it up best. “A language that doesn‘t affect the way you think about programming is not worth knowing“ With that in mind, here’s a selection of languages that I think are worth learning and that have certainly changed the way I think about tackling programming problems. Clojure Clojure is a Lisp-based language running on the Java Virtual Machine. The unique property of Lisp is homoiconicity, which means that a Lisp program is a Lisp data structure, and vice-versa. Since we can treat Lisp programs as Lisp data structures, we can write our code generation in the same style as our code. This gives Lisp a uniquely powerful macro system, and makes it ideal for implementing domain specific languages. Clojure also makes software transactional memory a first-class citizen, giving us a new approach to concurrency and dealing with the problems of shared state. Haskell Haskell is a strongly typed, functional programming language. Haskell’s type system is far richer than C# or Java, and allows us to push more of our application logic to compile-time safety. If it compiles, it usually works! Haskell is also a lazy language – we can work with infinite data structures. For example, in a board game we can generate the complete game tree, even if there are billions of possibilities, because the values are computed only as they are needed. Erlang Erlang is a functional language with a strong emphasis on reliability. Erlang’s approach to concurrency uses message passing instead of shared variables, with strong support from both the language itself and the virtual machine. Processes are extremely lightweight, and garbage collection doesn’t require all processes to be paused at the same time, making it feasible for a single program to use millions of processes at once, all without the mental overhead of managing shared state. The Benefits of Multilingualism By studying new languages, even if you won’t ever get the chance to use them in production, you will find yourself open to new ideas and ways of coding in your main language. For example, studying Haskell has taught me that you can do so much more with types and has changed my programming style in C#. A type represents some state a program should have, and a type should not be able to represent an invalid state. I often find myself refactoring methods like this… void SomeMethod(bool doThis, bool doThat) { if (!(doThis ^ doThat)) throw new ArgumentException(“At least one arg should be true”); if (doThis) DoThis(); if (doThat) DoThat(); } …into a type-based solution, like this: enum Action { DoThis, DoThat, Both }; void SomeMethod(Action action) { if (action == Action.DoThis || action == Action.Both) DoThis(); if (action == Action.DoThat || action == Action.Both) DoThat(); } At this point, I’ve removed the runtime exception in favor of a compile-time check. This is a trivial example, but is just one of many ideas that I’ve taken from one language and implemented in another.

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  • WiX, MSDeploy and an appealing configuration/deployment paradigm

    - by alexhildyard
    I do a lot of application and server configuration; I've done this for many years and have tended to view the complexity of this strictly in terms of the complexity of the ultimate configuration to be deployed. For example, specific APIs aside, I would tend to regard installing a server certificate as a more complex activity than, say, copying a file or adding a Registry entry.My prejudice revolved around the idea of a sequential deployment script that not only had the explicit prescription to apply a specific server configuration, but also made the implicit presumption that the server in question was in a good known state. Scripts like this fail for hundreds of reasons -- the Default Website didn't exist; the application had already been deployed; the application had already been partially deployed and failed to rollback fully, and so on. And so the problem is that the more complex the configuration activity, the more scope for error in any individual part of that activity, and therefore the greater the chance the server in question will not end up at exactly the desired configuration level.Recently I was introduced to a completely different mindset, which, for want of a better turn of phrase, I will call the "make it so" mindset. It's extremely simple both to explain and to implement. In place of the head-down, imperative script you used to use, you substitute a set of checks -- much like exception handlers -- around each configuration activity, starting with a check of the current system state. Thus the configuration logic becomes: "IF these services aren't started then start them, and IF XYZ website doesn't exist then create it, and IF these shares don't exist then create them, and IF these shares aren't permissioned in some particular way, then permission them so." This works. Really well, in my experience. Scenario 1: You want to get a system into a good known state; it's already in a good known state; you quickly realise there is nothing to do.Scenario 2: You want to get the system into a good known state; your script is flawed or the system is bust; it cannot be put into that state. You know exactly where (at least part of) the problem is and why.Scenario 3: You want to get the system into a good known state; people are fiddling around with the system just now. That's fine. You do what you can, and later you come back and try it againScenario 4: No one wants to deploy anything; they want you to prove that the previous deployment was successful. So you re-run the deployment script with the "-WhatIf" flag. It reports that there was nothing to change. There's your proof.I mentioned two technologies in the title -- MSI and MSDeploy. I am thinking specifically of the conversation that took place here. Having worked with both technologies, I think Rob Mensching's response is appropriately nuanced, and in essence the difference is this: sometimes your target is either to achieve a specific new server state, or to rollback to a known good one. Then again, your target may be to configure what you can, and to understand what you can't. Implicitly MSDeploy's "rollback" is simply to redeploy the previous version, whereas a well-crafted MSI will actively put your system into that state without further intervention. Either way, if all goes well it will leave you with a system in one of two states, whereas MSDeploy could leave your system in one of many states. The key is that MSDeploy and MSI are complementary technologies; which suits you best depends as much on Operational guidance as your Configuration remit.What I wanted to say was that I have always been for atomic, transactional-based configuration, but having worked with the "make it so" paradigm, I have been favourably impressed by the actual results. I'm tempted to put a more technical post up on this in due course.

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  • Omni-directional light shadow mapping with cubemaps in WebGL

    - by Winged
    First of all I must say, that I have read a lot of posts describing an usage of cubemaps, but I'm still confused about how to use them. My goal is to achieve a simple omni-directional (point) light type shading in my WebGL application. I know that there is a lot more techniques (like using Two-Hemispheres or Camera Space Shadow Mapping) which are way more efficient, but for an educational purpose cubemaps are my primary goal. Till now, I have adapted a simple shadow mapping which works with spotlights (with one exception: I don't know how to cut off the glitchy part beyond the reach of a single shadow map texture): glitchy shadow mapping<<< So for now, this is how I understand the usage of cubemaps in shadow mapping: Setup a framebuffer (in case of cubemaps - 6 framebuffers; 6 instead of 1 because every usage of framebufferTexture2D slows down an execution which is nicely described here <<<) and a texture cubemap. Also in WebGL depth components are not well supported, so I need to render it to RGBA first. this.texture = gl.createTexture(); gl.bindTexture(gl.TEXTURE_CUBE_MAP, this.texture); gl.texParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MIN_FILTER, gl.LINEAR); gl.texParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MAG_FILTER, gl.LINEAR); for (var face = 0; face < 6; face++) gl.texImage2D(gl.TEXTURE_CUBE_MAP_POSITIVE_X + face, 0, gl.RGBA, this.size, this.size, 0, gl.RGBA, gl.UNSIGNED_BYTE, null); gl.bindTexture(gl.TEXTURE_CUBE_MAP, null); this.framebuffer = []; for (face = 0; face < 6; face++) { this.framebuffer[face] = gl.createFramebuffer(); gl.bindFramebuffer(gl.FRAMEBUFFER, this.framebuffer[face]); gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_CUBE_MAP_POSITIVE_X + face, this.texture, 0); gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT, gl.RENDERBUFFER, this.depthbuffer); var e = gl.checkFramebufferStatus(gl.FRAMEBUFFER); // Check for errors if (e !== gl.FRAMEBUFFER_COMPLETE) throw "Cubemap framebuffer object is incomplete: " + e.toString(); } Setup the light and the camera (I'm not sure if should I store all of 6 view matrices and send them to shaders later, or is there a way to do it with just one view matrix). Render the scene 6 times from the light's position, each time in another direction (X, -X, Y, -Y, Z, -Z) for (var face = 0; face < 6; face++) { gl.bindFramebuffer(gl.FRAMEBUFFER, shadow.buffer.framebuffer[face]); gl.viewport(0, 0, shadow.buffer.size, shadow.buffer.size); gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT); camera.lookAt( light.position.add( cubeMapDirections[face] ) ); scene.draw(shadow.program); } In a second pass, calculate the projection a a current vertex using light's projection and view matrix. Now I don't know If should I calculate 6 of them, because of 6 faces of a cubemap. ScaleMatrix pushes the projected vertex into the 0.0 - 1.0 region. vDepthPosition = ScaleMatrix * uPMatrixFromLight * uVMatrixFromLight * vWorldVertex; In a fragment shader calculate the distance between the current vertex and the light position and check if it's deeper then the depth information read from earlier rendered shadow map. I know how to do it with a 2D Texture, but I have no idea how should I use cubemap texture here. I have read that texture lookups into cubemaps are performed by a normal vector instead of a UV coordinate. What vector should I use? Just a normalized vector pointing to the current vertex? For now, my code for this part looks like this (not working yet): float shadow = 1.0; vec3 depth = vDepthPosition.xyz / vDepthPosition.w; depth.z = length(vWorldVertex.xyz - uLightPosition) * linearDepthConstant; float shadowDepth = unpack(textureCube(uDepthMapSampler, vWorldVertex.xyz)); if (depth.z > shadowDepth) shadow = 0.5; Could you give me some hints or examples (preferably in WebGL code) how I should build it?

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  • Problem with creating a deterministic finite automata (DFA) - Mercury

    - by Jabba The hut
    I would like to have a deterministic finite automata (DFA) simulated in Mercury. But I’m s(t)uck at several places. Formally, a DFA is described with the following characteristics: a setOfStates S, an inputAlphabet E <-- summation symbol, a transitionFunction : S × E -- S, a startState s € S, a setOfAcceptableFinalStates F =C S. A DFA will always starts in the start state. Then the DFA will read all the characters on the input, one by one. Based on the current input character and the current state, there will be made to a new state. These transitions are defined in the transitions function. when the DFA is in one of his acceptable final states, after reading the last character, then will the DFA accept the input, If not, then the input will be is rejected. The figure shows a DFA the accepting strings where the amount of zeros, is a plurality of three. Condition 1 is the initial state, and also the only acceptable state. for each input character is the corresponding arc followed to the next state. Link to Figure What must be done A type “mystate” which represents a state. Each state has a number which is used for identification. A type “transition” that represents a possible transition between states. Each transition has a source_state, an input_character, and a final_state. A type “statemachine” that represents the entire DFA. In the solution, the DFA must have the following properties: The set of all states, the input alphabet, a transition function, represented as a set of possible transitions, a set of accepting final states, a current state of the DFA A predicate “init_machine (state machine :: out)” which unifies his arguments with the DFA, as shown as in the Figure. The current state for the DFA is set to his initial state, namely, 1. The input alphabet of the DFA is composed of the characters '0'and '1'. A user can enter a text, which will be controlled by the DFA. the program will continues until the user types Ctrl-D and simulates an EOF. If the user use characters that are not allowed into the input alphabet of the DFA, then there will be an error message end the program will close. (pred require) Example Enter a sentence: 0110 String is not ok! Enter a sentence: 011101 String is not ok! Enter a sentence: 110100 String is ok! Enter a sentence: 000110010 String is ok! Enter a sentence: 011102 Uncaught exception Mercury: Software Error: Character does not belong to the input alphabet! the thing wat I have. :- module dfa. :- interface. :- import_module io. :- pred main(io.state::di, io.state::uo) is det. :- implementation. :- import_module int,string,list,bool. 1 :- type mystate ---> state(int). 2 :- type transition ---> trans(source_state::mystate, input_character::bool, final_state::mystate). 3 (error, finale_state and current_state and input_character) :- type statemachine ---> dfa(list(mystate),list(input_character),list(transition),list(final_state),current_state(mystate)) 4 missing a lot :- pred init_machine(statemachine :: out) is det. %init_machine(statemachine(L_Mystate,0,L_transition,L_final_state,1)) :- <-probably fault 5 not perfect main(!IO) :- io.write_string("\nEnter a sentence: ", !IO), io.read_line_as_string(Input, !IO), ( Invoer = ok(StringVar), S1 = string.strip(StringVar), (if S1 = "mustbeabool" then io.write_string("Sentenceis Ok! ", !IO) else io.write_string("Sentence is not Ok!.", !IO)), main(!IO) ; Invoer = eof ; Invoer = error(ErrorCode), io.format("%s\n", [s(io.error_message(ErrorCode))], !IO) ). Hope you can help me kind regards

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  • C# 5 Async, Part 3: Preparing Existing code For Await

    - by Reed
    While the Visual Studio Async CTP provides a fantastic model for asynchronous programming, it requires code to be implemented in terms of Task and Task<T>.  The CTP adds support for Task-based asynchrony to the .NET Framework methods, and promises to have these implemented directly in the framework in the future.  However, existing code outside the framework will need to be converted to using the Task class prior to being usable via the CTP. Wrapping existing asynchronous code into a Task or Task<T> is, thankfully, fairly straightforward.  There are two main approaches to this. Code written using the Asynchronous Programming Model (APM) is very easy to convert to using Task<T>.  The TaskFactory class provides the tools to directly convert APM code into a method returning a Task<T>.  This is done via the FromAsync method.  This method takes the BeginOperation and EndOperation methods, as well as any parameters and state objects as arguments, and returns a Task<T> directly. For example, we could easily convert the WebRequest BeginGetResponse and EndGetResponse methods into a method which returns a Task<WebResponse> via: Task<WebResponse> task = Task.Factory .FromAsync<WebResponse>( request.BeginGetResponse, request.EndGetResponse, null); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Event-based Asynchronous Pattern (EAP) code can also be wrapped into a Task<T>, though this requires a bit more effort than the one line of code above.  This is handled via the TaskCompletionSource<T> class.  MSDN provides a detailed example of using this to wrap an EAP operation into a method returning Task<T>.  It demonstrates handling cancellation and exception handling as well as the basic operation of the asynchronous method itself. The basic form of this operation is typically: Task<YourResult> GetResultAsync() { var tcs = new TaskCompletionSource<YourResult>(); // Handle the event, and setup the task results... this.GetResultCompleted += (o,e) => { if (e.Error != null) tcs.TrySetException(e.Error); else if (e.Cancelled) tcs.TrySetCanceled(); else tcs.TrySetResult(e.Result); }; // Call the asynchronous method this.GetResult(); // Return the task from the TaskCompletionSource return tcs.Task; } We can easily use these methods to wrap our own code into a method that returns a Task<T>.  Existing libraries which cannot be edited can be extended via Extension methods.  The CTP uses this technique to add appropriate methods throughout the framework. The suggested naming for these methods is to define these methods as “Task<YourResult> YourClass.YourOperationAsync(…)”.  However, this naming often conflicts with the default naming of the EAP.  If this is the case, the CTP has standardized on using “Task<YourResult> YourClass.YourOperationTaskAsync(…)”. Once we’ve wrapped all of our existing code into operations that return Task<T>, we can begin investigating how the Async CTP can be used with our own code.

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  • Missing Fields and Default Values

    - by PointsToShare
    © 2011 By: Dov Trietsch. All rights reserved Dealing with Missing Fields and Default Values New fields and new default values are not propagated throughout the list. They only apply to new and updated items and not to items already entered. They are only prospective. We need to be able to deal with this issue. Here is a scenario. The user has an old list with old items and adds a new field. The field is not created for any of the old items. Trying to get its value raises an Argument Exception. Here is another: a default value is added to a field. All the old items, where the field was not assigned a value, do not get the new default value. The two can also happen in tandem – a new field is added with a default. The older items have neither. Even better, if the user changes the default value, the old items still carry the old defaults. Let’s go a bit further. You have already written code for the list, be it an event receiver, a feature receiver, a console app or a command extension, in which you span all the fields and run on selected items – some new (no problem) and some old (problems aplenty). Had you written defensive code, you would be able to handle the situation, including similar changes in the future. So, without further ado, here’s how. Instead of just getting the value of a field in an item – item[field].ToString() – use the function below. I use ItemValue(item, fieldname, “mud in your eye”) and if “mud in your eye” is what I get, I know that the item did not have the field.   /// <summary> /// Return the column value or a default value /// </summary> private static string ItemValue(SPItem item, string column, string defaultValue) {     try     {         return item[column].ToString();     }     catch (NullReferenceException ex)     {         return defaultValue;     }     catch (ArgumentException ex)     {         return defaultValue;     } } I also use a similar function to return the default and a funny default-default to ascertain that the default does not exist. Here it is:  /// <summary> /// return a fields default or the "default" default. /// </summary> public static string GetFieldDefault(SPField fld, string defValue) {     try     {         // -- Check if default exists.         return fld.DefaultValue.ToString();     }     catch (NullReferenceException ex)     {         return defValue;     }     catch (ArgumentException ex)     {         return defValue;     } } How is this defensive? You have trapped an expected error and dealt with it. Therefore the program did not stop cold in its track and the required code ran to its end. Now, take a further step - write to a log (See Logging – a log blog). Read your own log every now and then, and act accordingly. That’s all Folks!

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  • I am trying to create an windows application watcher? [migrated]

    - by Broken_Code
    I recently started coding in c #(in may this year) and well I find it best to learn by working with code. this application http://www.c-sharpcorner.com/UploadFile/satisharveti/ActiveApplicationWatcher01252007024921AM/ActiveApplicationWatcher.aspx. I am trying to recreate it however mine will be saving the information into an sql database(new at this as well). I am having some coding problems though as it does not do what I expect it to do. THis is the main code I am using. private void GetTotalTimer() { DateTime now = DateTime.Now; IntPtr hwnd = APIFunc.getforegroundWindow(); Int32 pid = APIFunc.GetWindowProcessID(hwnd); Process p = Process.GetProcessById(pid); appName = p.ProcessName; const int nChars = 256; int handle = 0; StringBuilder Buff = new StringBuilder(nChars); handle = GetForegroundWindow(); appltitle = APIFunc.ActiveApplTitle().Trim().Replace("\0", ""); //if (GetWindowText(handle, Buff, nChars) > 0) //{ // string strbuff = Buff.ToString(); // StrWindow = strbuff; #region insert statement try { if (Conn.State == ConnectionState.Closed) { Conn.Open(); } if (Conn.State == ConnectionState.Open) { SqlCommand com = new SqlCommand("Select top 1 [Window Title] From TimerLogs ORDER BY [Time of Event] DESC", Conn); SqlDataReader reader = com.ExecuteReader(); startTime = DateTime.Now; string time = now.ToString(); if (!reader.HasRows) { reader.Close(); cmd = new SqlCommand("insert into [TimerLogs] values(@time,@appName,@appltitle,@Elapsed_Time,@userName)", Conn); cmd.Parameters.AddWithValue("@time", time); cmd.Parameters.AddWithValue("@appName", appName); cmd.Parameters.AddWithValue("@appltitle", appltitle); cmd.Parameters.AddWithValue("@Elapsed_Time", blank.ToString()); cmd.Parameters.AddWithValue("@userName", userName); cmd.ExecuteNonQuery(); Conn.Close(); } else if(reader.HasRows) { reader.Read(); if (appltitle != reader.ToString()) { reader.Close(); endTime = DateTime.Now; appduration = endTime.Subtract(startTime); cmd = new SqlCommand("insert into [TimerLogs] values (@time,@appName,@appltitle,@Elapsed_Time,@userName)", Conn); cmd.Parameters.AddWithValue("@time", time); cmd.Parameters.AddWithValue("@appName", appName); cmd.Parameters.AddWithValue("@appltitle", appltitle); cmd.Parameters.AddWithValue("@Elapsed_Time", appduration.ToString()); cmd.Parameters.AddWithValue("@userName", userName); cmd.ExecuteNonQuery(); reader.Close(); Conn.Close(); } } } } catch (Exception) { } //} #endregion ActivityTimer.Start(); Processing = "Working"; } Unfortunately this is the result. it is not saving the data as I expect it to. What am i doing wrong I had thought that with the sql reader it would first check for a value and only save if they do not match however it is saving whether there is a match or not.

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