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• CodePlex Daily Summary for Saturday, October 29, 2011

  CodePlex Daily Summary for Saturday, October 29, 2011Popular Releasespatterns & practices: Enterprise Library Contrib: Enterprise Library Contrib - 5.0 (Oct 2011): This release of Enterprise Library Contrib is based on the Microsoft patterns & practices Enterprise Library 5.0 core and contains the following: Common extensionsTypeConfigurationElement<T> - A Polymorphic Configuration Element without having to be part of a PolymorphicConfigurationElementCollection. AnonymousConfigurationElement - A Configuration element that can be uniquely identified without having to define its name explicitly. Data Access Application Block extensionsMySql Provider - ...Network Monitor Open Source Parsers: Network Monitor Parsers 3.4.2748: The Network Monitor Parsers packages contain parsers for more than 400 network protocols, including RFC based public protocols and protocols for Microsoft products defined in the Microsoft Open Specifications for Windows and SQL Server. NetworkMonitor_Parsers.msi is the base parser package which defines parsers for commonly used public protocols and protocols for Microsoft Windows. In this release, NetowrkMonitor_Parsers.msi continues to improve quality and fix bugs. It has included the fo...Duckworth Lewis Professional Edition Calculator: DLcalc 3.0: DLcalc 3.0 can perform Duckworth/Lewis Professional Edition calculations 100% accurately. It also produces over-by-over and ball-by-ball PAR score tables.Folder Bookmarks: Folder Bookmarks 2.2.0.1: In this version: Custom Icons - now you can change the icons of the bookmarks. By default, whenever an image is added, the icon is automatically changed to a thumbnail of the picture. This can be turned off in the settings (Options... > Settings) Ability to remove items from the 'Recent' category Bugfixes - 'Choose' button in 'Edit Bookmark' now works Another bug fix: another problem in the 'Edit Bookmark' windowMedia Companion: MC 3.420b Weekly: Ensure .NET 4.0 Full Framework is installed. (Available from http://www.microsoft.com/download/en/details.aspx?id=17718) Ensure the NFO ID fix is applied when transitioning from versions prior to 3.416b. (Details here) Movies Fixed: Fanart and poster scraping issues TV Shows (Re)Added: Rebuild single show Fixed: Issue when shows are moved from original location Ability to handle " for actor nicknames Crash when episode name contains "<" (does not scrape yet) Clears fanart when switch...patterns & practices - Unity: Unity 3.0 for .NET4.5 Preview: The Unity 3.0.1026.0 Preview enables Unity to work on .NET 4.5 with both the WinRT and desktop profiles. The major changes include: Unity projects updated to target .NET 4.5. Dynamic build plans modified to use compiled lambda expressions instead of Reflection.Emit Converting reflection to use the new TypeInfo for reflection. Projects updated to work with the Microsoft Visual Studio 2011 Preview Notes/Known Issues: The Microsoft.Practices.Unity.UnityServiceLocator class cannot be use...Managed Extensibility Framework: MEF 2 Preview 4: Detailed information on this release is available on the BCL team blog.Image Converter: Image Converter 0.3: New Features: - English and German support Technical Improvements: - Microsoft All Rules using Code Analysis Planned Features for future release: 1. Unit testing 2. Command line interface 3. Automatic UpdatesAcDown????? - Anime&Comic Downloader: AcDown????? v3.6: ?? ● AcDown??????????、??????，??????????????????????，???????Acfun、Bilibili、???、???、???、Tucao.cc、SF???、?????80????，???????????、?????????。 ● AcDown???????????????????????????，???，???????????????????。 ● AcDown???????C#??，????.NET Framework 2.0??。?????"Acfun?????"。 ????32??64? Windows XP/Vista/7 ????????????? ??：????????Windows XP???,?????????.NET Framework 2.0???(x86)?.NET Framework 2.0???(x64)，?????"?????????"??? ??????????????，??????????： ??"AcDown?????"????????? ?? v3.6?? ??“????”...DotNetNuke® Events: 05.02.01: This release fixes any know bugs from any previous version. Events 05.02.01 will work for any DNN version 5.5.0 and up. Full details on the changes can be found at http://dnnevents.codeplex.com/workitem/list/basic Please review and rate this release... (stars are welcome)BUG FIXESAdded validation around category cookie RSS feed was missing an explicit close of the file when writing. Fixed. Added extra security into detail view .ICS Files did not include correct line folding. Fixed Cha...Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.33: Add JSParser.ParseExpression method to parse JavaScript expressions rather than source-elements. Add -strict switch (CodeSettings.StrictMode) to force input code to ECMA5 Strict-mode (extra error-checking, "use strict" at top). Fixed bug when MinifyCode setting was set to false but RemoveUnneededCode was left it's default value of true.Path Copy Copy: 8.0: New version that mostly adds lots of requested features: 11340 11339 11338 11337 This version also features a more elaborate Settings UI that has several tabs. I tried to add some notes to better explain the use and purpose of the various options. The Path Copy Copy documentation is also on the way, both to explain how to develop custom plugins and to explain how to pre-configure options if you're a network admin. Stay tuned.MVC Controls Toolkit: Mvc Controls Toolkit 1.5.0: Added: The new Client Blocks feaure of Views A new "move" js method for the TreeViews The NewHtmlCreated js event to the DataGrid Improved the ChoiceList structure that now allows also the selection list of a dropdown to be chosen with a lambda expression Improved the AcceptViewHintAttribute controller filter. Now a client can specify not only the name of a View or Partial View it prefers, but also to receive just the rough data in Json format. Fixed: Issue with partial thrust Cl...Free SharePoint Master Pages: Buried Alive (Halloween) Theme: Release Notes *Created for Halloween, you will find theme file, custom css file and images. *Created by Al Roome @AlstarRoome Features: Custom styling for web part Custom background *Screenshot https://s3.amazonaws.com/kkhipple/post/sharepoint-showcase-halloween.pngDevForce Application Framework: DevForce AF 2.0.3 RTW: PrerequisitesWPF 4.0 Silverlight 4.0 DevForce 2010 6.1.3.1 Download ContentsDebug and Release Assemblies API Documentation Source code License.txt Requirements.txt Release HighlightsNew: EventAggregator event forwarding New: EntityManagerInterceptor<T> to intercept EntityManger events New: IHarnessAware to allow for ViewModel setup when executed inside of the Development Harness New: Improved design time stability New: Support for add-in development New: CoroutineFns.To...NicAudio: NicAudio 2.0.5: Minor change to accept special DTS stereo modes (LtRt, AB,...)NDepend TFS 2010 integration: version 0.5.0 beta 1: Only the activity and the VS plugin are avalaible right now. They basically work. Data types that are logged into tfs reports are subject to change. This is no big deal since data is not yet sent into the warehouse.Windows Azure Toolkit for Windows Phone: Windows Azure Toolkit for Windows Phone v1.3.1: Upgraded Windows Azure projects to Windows Azure Tools for Microsoft Visual Studio 2010 1.5 – September 2011 Upgraded the tools tools to support the Windows Phone Developer Tools RTW Update SQL Azure only scenarios to use ASP.NET Universal Providers (through the System.Web.Providers v1.0.1 NuGet package) Changed Shared Access Signature service interface to support more operations Refactored Blobs API to have a similar interface and usage to that provided by the Windows Azure SDK Stor...DotNetNuke® FAQ: 05.00.00: FAQ (Frequently Asked Questions) 05.00.00 will work for any DNN version 5.6.1 and up. It is the first version which is rewritten in C#. The scope of this update is to fix all known issues and improve user interface. Please review and rate this release... (stars are welcome)BUG FIXESManage Categories button text was not localized Edit/Add FAQ Entry: button text was not localized ENHANCEMENTSAdded an option to select the control for category display: Listbox with checkboxes (flat category ...SiteMap Editor for Microsoft Dynamics CRM 2011: SiteMap Editor (1.0.921.340): Added CodePlex and PayPal links New iconNew ProjectsAsynk: Asynk is a framework/application that allows existing applications to easily be extended with an offloaded asynchronous worker layer. Asynk is developed using C#.Blob Tower Defense: 3D tower defense game for Windows Phone 7. School project for Brno University of Technology, computer graphics class.Booz: Booz is... An extended version of the boo shell (booish2 to be precise). Offers additional commands like cd, md, ls etc. I hope this shell can be used to take the position of/surpass the native windows shell in the near future.CIMS: a sanction infomation system for sencience and technology of hustCrystalDot - Icon Collection / Pack (LGPL): .Net / Mono freundliche Varainte der Crystal-Icons von Everaldo Icon collection / pack for .NET and Mono designed by Everaldo - KDE style http://www.everaldo.com/crystal/dotetes: dotetes adalah teka teki silang tool dikembangkan dengan bahasa c#Emoe': This Project is a Windows Phone 7.1 application.Equation Inversion: Visual Studion 2008 Add-in for equation inversions.Exploring VMR Features on WEC7: This is the sample application helps you to do alpha blending the bitmap on camera streaming in Windows Embedded Compact 7 using Directshow video Renderer (VMR). It is a VS2008 based smart device project developed on C++. I have explained the sample application in the following blog link. http://www.e-consystems.com/blog/windowsce/?p=759 EzValidation: Custom validation extensions for ASP.NET MVC 3. Includes server and client side model based validation attributes for: -- Equal To -- Not Equal To -- Greater Than -- Greater Than or Equal To -- Less Than -- Less Than or Equal To Supports validating against: -- Another Model Field -- A Specific Value -- Current Date/Yesterday/Tomorrow (for Dates and Strings) Download & Install via NuGet "package-install ezvalidation"Flu.net: Flu.net is a tool that helps you creating your own fluent syntax for .NET Framework applications in a declarative fashion. It is aimed for infrastructures and other open-source projects use.For Chess Endgames: King vs. King Opposition Calculator: You must input the locations of 2 kings on a chessboard, and whose turn it is to move. The calculator will display which king has the opposition, and how it can be used or maintained.GameTrakXNA: This project aims to create a simple library to use the unique GameTrak controller within XNA and Flash.Google Speech Recognition Example: Google Speech Recognition contains a working example of application that uses google speech recognition API. App contains all necessary dlls to record, decode and send your voice request to google service and recieve a text representation of what you've said. It's developed in C#Interval Mandelbrot Explorer: Explore the Mandelbrot set using interval arithmetic.ISD training tasks: ISD training examples and tasksiTunesControlBar: The iTunesControlBar helps user control their iTunes Application while it is minimized. iTunesControlBar resides at the top of the screen, invisible when not used, and allows playback and volume control, library searches and media information without the need to bring up iTunes.iTurtle: A bunch of Powerscripts to automate server management in AD environment.M26WC - Mono 2.6 Wizard Control: Wizard which runs under Mono2.6 A fork of: http://aerowizard.codeplex.com/Microsoft Help Viewer 2: Help Viewer 2 is the help runtime for both Visual Studio 11 help and Windows 8 help. The code in this project will help you use and understand the HV2 runtime API.MONTRASEC: Monitoring Trafficking in human beings and Sexual Exploitation of Children: benchmarking for member state and EU reporting, turning the SIAMSECT templates into a user-friendly interface and reporting tool. MTF.NET Runtime: Managed Task Framework .NET Runtime The MTF.NET runtime software and resulting assemblies are required to run applications built using the Managed Task Framework.NET Professional (Visual Studio 2010 extension) software design editor. The MTF.NET team are committed to continuously improving the core MTF.NET runtime and ensuring it is always available free and fully transparent. Pandoras Box: A greenfield inversion of control project utilising the power and flexibility of expressions and preferring convention over configuration.Pass the Puzzle: Pass the Puzzle is a frantic word-guessing party game. The game displays a few letters, and the players must come up with words containing those letters. But beware: if the timer goes off, you lose! It is based on the folk party game Pass the Parcel and is written in C#.PerCiGal: Percigal is a project for the development of applications for managing your personal media library. It consists in - a windows application to use at home to catalog movies, TV series, cast and books, with the support of the Internet for information retrieval; - a web interface for viewing and cataloging everywhere your media; - an application for smartphones. Project Flying Carpet: Este jogo é um projeto para a cadeira Projeto de Jogos: Motores Jogos do curso de Jogos Digitais da Unisinos.proxy browser: sed leo Latin's Butterfly....Python Multiple Dispatch: Multiple dispatch (AKA multimethods) for Python 3 via a metaclass and type annotations.reDune: ?????????? ???? ? ????? «????????? ? ???????? ???????». ???????? ?? Dune2000 ?? Westwood ? Electronic Arts.Rereadable: Keep page from internet for read it latter.ServStop: ServStop is a .NET application that makes it easy to stop several system services at once. Now you don't have to change startup types or stop them one at a time. It has a simple list-based interface with the ability to save and load lists of user services to stop. Written in C#.SharePoint 2010 Audience Membership Workflow Activity (Full Trust): A simple SharePoint 2010 workflow activity / workflow condition to check whether the user initiating the workflow is a member of a specified audience. Farm-level .wsp solution, written in C#. Once installed, the workflow activity can be used in SharePoint Designer 2010 declarative workflows.SQL Server® to Firebird DB converter: Converts Microsoft SQL Server® database into Firebird database including entire structure and datastegitest: test projectSystem.Threading.Joins: The Joins project provides asynchronous concurrency semantics based on join calculus and modeled after the Microsoft Research C? (C Omega) project.TestAndroidGame: try dev a TestAndroidGametetribricks: block game Topographic Explorer: A project to import, convert, explore, manipulate, and save topographical maps. Looking to use C# and WPF.Trading: Under construction!!!Trombone: Trombone makes it easier for Windows Mobile Professional users to automate status reply through SMS. It's developed in Visual C# 2008.Tulsa SharePoint Interest Group: Repository for source code for the Tulsa SharePoint Interest Group's web site. The Tulsa SharePoint Interest Group is using the Community Kit for SharePoint. This project will house any modifications that are specific to our user group.World of Tanks RU tiny stats collection utilty.: Tiny utility to load players stats for World of Tanks RU server. Results saved to comma separated file.WS-Discovery Proxy: Attempt at creating general purpose WS-Discovery Proxy.Yamaha Tu?n Tr?c: This application is used to manage information for Yamaha Tu?n Tr?c

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• Dynamic Filtering

  - by Ricardo Peres

  Continuing my previous posts on dynamic LINQ, now it's time for dynamic filtering. For now, I'll focus on string matching. There are three standard operators for string matching, which both NHibernate, Entity Framework and LINQ to SQL recognize: Equals Contains StartsWith EndsWith So, if we want to apply filtering by one of these operators on a string property, we can use this code: public enum MatchType { StartsWith = 0, EndsWith = 1, Contains = 2, Equals = 3 } public static List Filter(IEnumerable enumerable, String propertyName, String filter, MatchType matchType) { return (Filter(enumerable, typeof(T), propertyName, filter, matchType) as List); } public static IList Filter(IEnumerable enumerable, Type elementType, String propertyName, String filter, MatchType matchType) { MethodInfo asQueryableMethod = typeof(Queryable).GetMethods(BindingFlags.Static | BindingFlags.Public).Where(m = (m.Name == "AsQueryable") && (m.ContainsGenericParameters == false)).Single(); IQueryable query = (enumerable is IQueryable) ? (enumerable as IQueryable) : asQueryableMethod.Invoke(null, new Object [] { enumerable }) as IQueryable; MethodInfo whereMethod = typeof(Queryable).GetMethods(BindingFlags.Public | BindingFlags.Static).Where(m = m.Name == "Where").ToArray() [ 0 ].MakeGenericMethod(elementType); MethodInfo matchMethod = typeof(String).GetMethod ( (matchType == MatchType.StartsWith) ? "StartsWith" : (matchType == MatchType.EndsWith) ? "EndsWith" : (matchType == MatchType.Contains) ? "Contains" : "Equals", new Type [] { typeof(String) } ); PropertyInfo displayProperty = elementType.GetProperty(propertyName, BindingFlags.Public | BindingFlags.Instance); MemberExpression member = Expression.MakeMemberAccess(Expression.Parameter(elementType, "n"), displayProperty); MethodCallExpression call = Expression.Call(member, matchMethod, Expression.Constant(filter)); LambdaExpression where = Expression.Lambda(call, member.Expression as ParameterExpression); query = whereMethod.Invoke(null, new Object [] { query, where }) as IQueryable; MethodInfo toListMethod = typeof(Enumerable).GetMethod("ToList", BindingFlags.Static | BindingFlags.Public).MakeGenericMethod(elementType); IList list = toListMethod.Invoke(null, new Object [] { query }) as IList; return (list); } var list = new [] { new { A = "aa" }, new { A = "aabb" }, new { A = "ccaa" }, new { A = "ddaadd" } }; var contains = Filter(list, "A", "aa", MatchType.Contains); var endsWith = Filter(list, "A", "aa", MatchType.EndsWith); var startsWith = Filter(list, "A", "aa", MatchType.StartsWith); var equals = Filter(list, "A", "aa", MatchType.Equals); Perhaps I'll write some more posts on this subject in the near future. SyntaxHighlighter.config.clipboardSwf = 'http://alexgorbatchev.com/pub/sh/2.0.320/scripts/clipboard.swf'; SyntaxHighlighter.brushes.CSharp.aliases = ['c#', 'c-sharp', 'csharp']; SyntaxHighlighter.all();

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• Using the ASP.NET Cache to cache data in a Model or Business Object layer, without a dependency on System.Web in the layer - Part One.

  - by Rhames

  ASP.NET applications can make use of the System.Web.Caching.Cache object to cache data and prevent repeated expensive calls to a database or other store. However, ideally an application should make use of caching at the point where data is retrieved from the database, which typically is inside a Business Objects or Model layer. One of the key features of using a UI pattern such as Model-View-Presenter (MVP) or Model-View-Controller (MVC) is that the Model and Presenter (or Controller) layers are developed without any knowledge of the UI layer. Introducing a dependency on System.Web into the Model layer would break this independence of the Model from the View. This article gives a solution to this problem, using dependency injection to inject the caching implementation into the Model layer at runtime. This allows caching to be used within the Model layer, without any knowledge of the actual caching mechanism that will be used. Create a sample application to use the caching solution Create a test SQL Server database This solution uses a SQL Server database with the same Sales data used in my previous post on calculating running totals. The advantage of using this data is that it gives nice slow queries that will exaggerate the effect of using caching! To create the data, first create a new SQL database called CacheSample. Next run the following script to create the Sale table and populate it: USE CacheSample GO   CREATE TABLE Sale(DayCount smallint, Sales money) CREATE CLUSTERED INDEX ndx_DayCount ON Sale(DayCount) go INSERT Sale VALUES (1,120) INSERT Sale VALUES (2,60) INSERT Sale VALUES (3,125) INSERT Sale VALUES (4,40)   DECLARE @DayCount smallint, @Sales money SET @DayCount = 5 SET @Sales = 10   WHILE @DayCount < 5000  BEGIN  INSERT Sale VALUES (@DayCount,@Sales)  SET @DayCount = @DayCount + 1  SET @Sales = @Sales + 15  END Next create a stored procedure to calculate the running total, and return a specified number of rows from the Sale table, using the following script: USE [CacheSample] GO   SET ANSI_NULLS ON GO   SET QUOTED_IDENTIFIER ON GO   -- ============================================= -- Author:        Robin -- Create date: -- Description:   -- ============================================= CREATE PROCEDURE [dbo].[spGetRunningTotals]       -- Add the parameters for the stored procedure here       @HighestDayCount smallint = null AS BEGIN       -- SET NOCOUNT ON added to prevent extra result sets from       -- interfering with SELECT statements.       SET NOCOUNT ON;         IF @HighestDayCount IS NULL             SELECT @HighestDayCount = MAX(DayCount) FROM dbo.Sale                   DECLARE @SaleTbl TABLE (DayCount smallint, Sales money, RunningTotal money)         DECLARE @DayCount smallint,                   @Sales money,                   @RunningTotal money         SET @RunningTotal = 0       SET @DayCount = 0         DECLARE rt_cursor CURSOR       FOR       SELECT DayCount, Sales       FROM Sale       ORDER BY DayCount         OPEN rt_cursor         FETCH NEXT FROM rt_cursor INTO @DayCount,@Sales         WHILE @@FETCH_STATUS = 0 AND @DayCount <= @HighestDayCount        BEGIN        SET @RunningTotal = @RunningTotal + @Sales        INSERT @SaleTbl VALUES (@DayCount,@Sales,@RunningTotal)        FETCH NEXT FROM rt_cursor INTO @DayCount,@Sales        END         CLOSE rt_cursor       DEALLOCATE rt_cursor         SELECT DayCount, Sales, RunningTotal       FROM @SaleTbl   END   GO   Create the Sample ASP.NET application In Visual Studio create a new solution and add a class library project called CacheSample.BusinessObjects and an ASP.NET web application called CacheSample.UI. The CacheSample.BusinessObjects project will contain a single class to represent a Sale data item, with all the code to retrieve the sales from the database included in it for simplicity (normally I would at least have a separate Repository or other object that is responsible for retrieving data, and probably a data access layer as well, but for this sample I want to keep it simple). The C# code for the Sale class is shown below: using System; using System.Collections.Generic; using System.Data; using System.Data.SqlClient;   namespace CacheSample.BusinessObjects {     public class Sale     {         public Int16 DayCount { get; set; }         public decimal Sales { get; set; }         public decimal RunningTotal { get; set; }           public static IEnumerable<Sale> GetSales(int? highestDayCount)         {             List<Sale> sales = new List<Sale>();               SqlParameter highestDayCountParameter = new SqlParameter("@HighestDayCount", SqlDbType.SmallInt);             if (highestDayCount.HasValue)                 highestDayCountParameter.Value = highestDayCount;             else                 highestDayCountParameter.Value = DBNull.Value;               string connectionStr = System.Configuration.ConfigurationManager .ConnectionStrings["CacheSample"].ConnectionString;               using(SqlConnection sqlConn = new SqlConnection(connectionStr))             using (SqlCommand sqlCmd = sqlConn.CreateCommand())             {                 sqlCmd.CommandText = "spGetRunningTotals";                 sqlCmd.CommandType = CommandType.StoredProcedure;                 sqlCmd.Parameters.Add(highestDayCountParameter);                   sqlConn.Open();                   using (SqlDataReader dr = sqlCmd.ExecuteReader())                 {                     while (dr.Read())                     {                         Sale newSale = new Sale();                         newSale.DayCount = dr.GetInt16(0);                         newSale.Sales = dr.GetDecimal(1);                         newSale.RunningTotal = dr.GetDecimal(2);                           sales.Add(newSale);                     }                 }             }               return sales;         }     } }   The static GetSale() method makes a call to the spGetRunningTotals stored procedure and then reads each row from the returned SqlDataReader into an instance of the Sale class, it then returns a List of the Sale objects, as IEnnumerable<Sale>. A reference to System.Configuration needs to be added to the CacheSample.BusinessObjects project so that the connection string can be read from the web.config file. In the CacheSample.UI ASP.NET project, create a single web page called ShowSales.aspx, and make this the default start up page. This page will contain a single button to call the GetSales() method and a label to display the results. The html mark up and the C# code behind are shown below: ShowSales.aspx <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ShowSales.aspx.cs" Inherits="CacheSample.UI.ShowSales" %>   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">   <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server">     <title>Cache Sample - Show All Sales</title> </head> <body>     <form id="form1" runat="server">     <div>         <asp:Button ID="btnTest1" runat="server" onclick="btnTest1_Click"             Text="Get All Sales" />         &nbsp;&nbsp;&nbsp;         <asp:Label ID="lblResults" runat="server"></asp:Label>         </div>     </form> </body> </html>   ShowSales.aspx.cs using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls;   using CacheSample.BusinessObjects;   namespace CacheSample.UI {     public partial class ShowSales : System.Web.UI.Page     {         protected void Page_Load(object sender, EventArgs e)         {         }           protected void btnTest1_Click(object sender, EventArgs e)         {             System.Diagnostics.Stopwatch stopWatch = new System.Diagnostics.Stopwatch();             stopWatch.Start();               var sales = Sale.GetSales(null);               var lastSales = sales.Last();               stopWatch.Stop();               lblResults.Text = string.Format( "Count of Sales: {0}, Last DayCount: {1}, Total Sales: {2}. Query took {3} ms", sales.Count(), lastSales.DayCount, lastSales.RunningTotal, stopWatch.ElapsedMilliseconds);         }       } }   Finally we need to add a connection string to the CacheSample SQL Server database, called CacheSample, to the web.config file: <?xmlversion="1.0"?>   <configuration>    <connectionStrings>     <addname="CacheSample"          connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;Initial Catalog=CacheSample"          providerName="System.Data.SqlClient" />  </connectionStrings>    <system.web>     <compilationdebug="true"targetFramework="4.0" />  </system.web>   </configuration>   Run the application and click the button a few times to see how long each call to the database takes. On my system, each query takes about 450ms. Next I shall look at a solution to use the ASP.NET caching to cache the data returned by the query, so that subsequent requests to the GetSales() method are much faster. Adding Data Caching Support I am going to create my caching support in a separate project called CacheSample.Caching, so the next step is to add a class library to the solution. We shall be using the application configuration to define the implementation of our caching system, so we need a reference to System.Configuration adding to the project. ICacheProvider<T> Interface The first step in adding caching to our application is to define an interface, called ICacheProvider, in the CacheSample.Caching project, with methods to retrieve any data from the cache or to retrieve the data from the data source if it is not present in the cache. Dependency Injection will then be used to inject an implementation of this interface at runtime, allowing the users of the interface (i.e. the CacheSample.BusinessObjects project) to be completely unaware of how the caching is actually implemented. As data of any type maybe retrieved from the data source, it makes sense to use generics in the interface, with a generic type parameter defining the data type associated with a particular instance of the cache interface implementation. The C# code for the ICacheProvider interface is shown below: using System; using System.Collections.Generic;   namespace CacheSample.Caching {     public interface ICacheProvider     {     }       public interface ICacheProvider<T> : ICacheProvider     {         T Fetch(string key, Func<T> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry);           IEnumerable<T> Fetch(string key, Func<IEnumerable<T>> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry);     } }   The empty non-generic interface will be used as a type in a Dictionary generic collection later to store instances of the ICacheProvider<T> implementation for reuse, I prefer to use a base interface when doing this, as I think the alternative of using object makes for less clear code. The ICacheProvider<T> interface defines two overloaded Fetch methods, the difference between these is that one will return a single instance of the type T and the other will return an IEnumerable<T>, providing support for easy caching of collections of data items. Both methods will take a key parameter, which will uniquely identify the cached data, a delegate of type Func<T> or Func<IEnumerable<T>> which will provide the code to retrieve the data from the store if it is not present in the cache, and absolute or relative expiry policies to define when a cached item should expire. Note that at present there is no support for cache dependencies, but I shall be showing a method of adding this in part two of this article. CacheProviderFactory Class We need a mechanism of creating instances of our ICacheProvider<T> interface, using Dependency Injection to get the implementation of the interface. To do this we shall create a CacheProviderFactory static class in the CacheSample.Caching project. This factory will provide a generic static method called GetCacheProvider<T>(), which shall return instances of ICacheProvider<T>. We can then call this factory method with the relevant data type (for example the Sale class in the CacheSample.BusinessObject project) to get a instance of ICacheProvider for that type (e.g. call CacheProviderFactory.GetCacheProvider<Sale>() to get the ICacheProvider<Sale> implementation). The C# code for the CacheProviderFactory is shown below: using System; using System.Collections.Generic;   using CacheSample.Caching.Configuration;   namespace CacheSample.Caching {     public static class CacheProviderFactory     {         private static Dictionary<Type, ICacheProvider> cacheProviders = new Dictionary<Type, ICacheProvider>();         private static object syncRoot = new object();           ///<summary>         /// Factory method to create or retrieve an implementation of the  /// ICacheProvider interface for type <typeparamref name="T"/>.         ///</summary>         ///<typeparam name="T">  /// The type that this cache provider instance will work with  ///</typeparam>         ///<returns>An instance of the implementation of ICacheProvider for type  ///<typeparamref name="T"/>, as specified by the application  /// configuration</returns>         public static ICacheProvider<T> GetCacheProvider<T>()         {             ICacheProvider<T> cacheProvider = null;             // Get the Type reference for the type parameter T             Type typeOfT = typeof(T);               // Lock the access to the cacheProviders dictionary             // so multiple threads can work with it             lock (syncRoot)             {                 // First check if an instance of the ICacheProvider implementation  // already exists in the cacheProviders dictionary for the type T                 if (cacheProviders.ContainsKey(typeOfT))                     cacheProvider = (ICacheProvider<T>)cacheProviders[typeOfT];                 else                 {                     // There is not already an instance of the ICacheProvider in       // cacheProviders for the type T                     // so we need to create one                       // Get the Type reference for the application's implementation of       // ICacheProvider from the configuration                     Type cacheProviderType = Type.GetType(CacheProviderConfigurationSection.Current. CacheProviderType);                     if (cacheProviderType != null)                     {                         // Now get a Type reference for the Cache Provider with the                         // type T generic parameter                         Type typeOfCacheProviderTypeForT = cacheProviderType.MakeGenericType(new Type[] { typeOfT });                         if (typeOfCacheProviderTypeForT != null)                         {                             // Create the instance of the Cache Provider and add it to // the cacheProviders dictionary for future use                             cacheProvider = (ICacheProvider<T>)Activator. CreateInstance(typeOfCacheProviderTypeForT);                             cacheProviders.Add(typeOfT, cacheProvider);                         }                     }                 }             }               return cacheProvider;                 }     } }   As this code uses Activator.CreateInstance() to create instances of the ICacheProvider<T> implementation, which is a slow process, the factory class maintains a Dictionary of the previously created instances so that a cache provider needs to be created only once for each type. The type of the implementation of ICacheProvider<T> is read from a custom configuration section in the application configuration file, via the CacheProviderConfigurationSection class, which is described below. CacheProviderConfigurationSection Class The implementation of ICacheProvider<T> will be specified in a custom configuration section in the application’s configuration. To handle this create a folder in the CacheSample.Caching project called Configuration, and add a class called CacheProviderConfigurationSection to this folder. This class will extend the System.Configuration.ConfigurationSection class, and will contain a single string property called CacheProviderType. The C# code for this class is shown below: using System; using System.Configuration;   namespace CacheSample.Caching.Configuration {     internal class CacheProviderConfigurationSection : ConfigurationSection     {         public static CacheProviderConfigurationSection Current         {             get             {                 return (CacheProviderConfigurationSection) ConfigurationManager.GetSection("cacheProvider");             }         }           [ConfigurationProperty("type", IsRequired=true)]         public string CacheProviderType         {             get             {                 return (string)this["type"];             }         }     } }   Adding Data Caching to the Sales Class We now have enough code in place to add caching to the GetSales() method in the CacheSample.BusinessObjects.Sale class, even though we do not yet have an implementation of the ICacheProvider<T> interface. We need to add a reference to the CacheSample.Caching project to CacheSample.BusinessObjects so that we can use the ICacheProvider<T> interface within the GetSales() method. Once the reference is added, we can first create a unique string key based on the method name and the parameter value, so that the same cache key is used for repeated calls to the method with the same parameter values. Then we get an instance of the cache provider for the Sales type, using the CacheProviderFactory, and pass the existing code to retrieve the data from the database as the retrievalMethod delegate in a call to the Cache Provider Fetch() method. The C# code for the modified GetSales() method is shown below: public static IEnumerable<Sale> GetSales(int? highestDayCount) {     string cacheKey = string.Format("CacheSample.BusinessObjects.GetSalesWithCache({0})", highestDayCount);       return CacheSample.Caching.CacheProviderFactory. GetCacheProvider<Sale>().Fetch(cacheKey,         delegate()         {             List<Sale> sales = new List<Sale>();               SqlParameter highestDayCountParameter = new SqlParameter("@HighestDayCount", SqlDbType.SmallInt);             if (highestDayCount.HasValue)                 highestDayCountParameter.Value = highestDayCount;             else                 highestDayCountParameter.Value = DBNull.Value;               string connectionStr = System.Configuration.ConfigurationManager. ConnectionStrings["CacheSample"].ConnectionString;               using (SqlConnection sqlConn = new SqlConnection(connectionStr))             using (SqlCommand sqlCmd = sqlConn.CreateCommand())             {                 sqlCmd.CommandText = "spGetRunningTotals";                 sqlCmd.CommandType = CommandType.StoredProcedure;                 sqlCmd.Parameters.Add(highestDayCountParameter);                   sqlConn.Open();                   using (SqlDataReader dr = sqlCmd.ExecuteReader())                 {                     while (dr.Read())                     {                         Sale newSale = new Sale();                         newSale.DayCount = dr.GetInt16(0);                         newSale.Sales = dr.GetDecimal(1);                         newSale.RunningTotal = dr.GetDecimal(2);                           sales.Add(newSale);                     }                 }             }               return sales;         },         null,         new TimeSpan(0, 10, 0)); }     This example passes the code to retrieve the Sales data from the database to the Cache Provider as an anonymous method, however it could also be written as a lambda. The main advantage of using an anonymous function (method or lambda) is that the code inside the anonymous function can access the parameters passed to the GetSales() method. Finally the absolute expiry is set to null, and the relative expiry set to 10 minutes, to indicate that the cache entry should be removed 10 minutes after the last request for the data. As the ICacheProvider<T> has a Fetch() method that returns IEnumerable<T>, we can simply return the results of the Fetch() method to the caller of the GetSales() method. This should be all that is needed for the GetSales() method to now retrieve data from a cache after the first time the data has be retrieved from the database. Implementing a ASP.NET Cache Provider The final step is to actually implement the ICacheProvider<T> interface, and add the implementation details to the web.config file for the dependency injection. The cache provider implementation needs to have access to System.Web. Therefore it could be placed in the CacheSample.UI project, or in its own project that has a reference to System.Web. Implementing the Cache Provider in a separate project is my favoured approach. Create a new project inside the solution called CacheSample.CacheProvider, and add references to System.Web and CacheSample.Caching to this project. Add a class to the project called AspNetCacheProvider. Make the class a generic class by adding the generic parameter <T> and indicate that the class implements ICacheProvider<T>. The C# code for the AspNetCacheProvider class is shown below: using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.Caching;   using CacheSample.Caching;   namespace CacheSample.CacheProvider {     public class AspNetCacheProvider<T> : ICacheProvider<T>     {         #region ICacheProvider<T> Members           public T Fetch(string key, Func<T> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry)         {             return FetchAndCache<T>(key, retrieveData, absoluteExpiry, relativeExpiry);         }           public IEnumerable<T> Fetch(string key, Func<IEnumerable<T>> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry)         {             return FetchAndCache<IEnumerable<T>>(key, retrieveData, absoluteExpiry, relativeExpiry);         }           #endregion           #region Helper Methods           private U FetchAndCache<U>(string key, Func<U> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry)         {             U value;             if (!TryGetValue<U>(key, out value))             {                 value = retrieveData();                 if (!absoluteExpiry.HasValue)                     absoluteExpiry = Cache.NoAbsoluteExpiration;                   if (!relativeExpiry.HasValue)                     relativeExpiry = Cache.NoSlidingExpiration;                   HttpContext.Current.Cache.Insert(key, value, null, absoluteExpiry.Value, relativeExpiry.Value);             }             return value;         }           private bool TryGetValue<U>(string key, out U value)         {             object cachedValue = HttpContext.Current.Cache.Get(key);             if (cachedValue == null)             {                 value = default(U);                 return false;             }             else             {                 try                 {                     value = (U)cachedValue;                     return true;                 }                 catch                 {                     value = default(U);                     return false;                 }             }         }           #endregion       } }   The two interface Fetch() methods call a private method called FetchAndCache(). This method first checks for a element in the HttpContext.Current.Cache with the specified cache key, and if so tries to cast this to the specified type (either T or IEnumerable<T>). If the cached element is found, the FetchAndCache() method simply returns it. If it is not found in the cache, the method calls the retrievalMethod delegate to get the data from the data source, and then adds this to the HttpContext.Current.Cache. The final step is to add the AspNetCacheProvider class to the relevant custom configuration section in the CacheSample.UI.Web.Config file. To do this there needs to be a <configSections> element added as the first element in <configuration>. This will match a custom section called <cacheProvider> with the CacheProviderConfigurationSection. Then we add a <cacheProvider> element, with a type property set to the fully qualified assembly name of the AspNetCacheProvider class, as shown below: <?xmlversion="1.0"?>   <configuration>  <configSections>     <sectionname="cacheProvider" type="CacheSample.Base.Configuration.CacheProviderConfigurationSection, CacheSample.Base" />  </configSections>    <connectionStrings>     <addname="CacheSample"          connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;Initial Catalog=CacheSample"          providerName="System.Data.SqlClient" />  </connectionStrings>    <cacheProvidertype="CacheSample.CacheProvider.AspNetCacheProvider`1, CacheSample.CacheProvider, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null">  </cacheProvider>    <system.web>     <compilationdebug="true"targetFramework="4.0" />  </system.web>   </configuration>   One point to note is that the fully qualified assembly name of the AspNetCacheProvider class includes the notation `1 after the class name, which indicates that it is a generic class with a single generic type parameter. The CacheSample.UI project needs to have references added to CacheSample.Caching and CacheSample.CacheProvider so that the actual application is aware of the relevant cache provider implementation. Conclusion After implementing this solution, you should have a working cache provider mechanism, that will allow the middle and data access layers to implement caching support when retrieving data, without any knowledge of the actually caching implementation. If the UI is not ASP.NET based, if for example it is Winforms or WPF, the implementation of ICacheProvider<T> would be written around whatever technology is available. It could even be a standalone caching system that takes full responsibility for adding and removing items from a global store. The next part of this article will show how this caching mechanism may be extended to provide support for cache dependencies, such as the System.Web.Caching.SqlCacheDependency. Another possible extension would be to cache the cache provider implementations instead of storing them in a static Dictionary in the CacheProviderFactory. This would prevent a build up of seldom used cache providers in the application memory, as they could be removed from the cache if not used often enough, although in reality there are probably unlikely to be vast numbers of cache provider implementation instances, as most applications do not have a massive number of business object or model types.

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• Don't Miss At Devoxx!!!

  - by Yolande Poirier

  Come by IoT Hack Fest which starts with the session: kickstart your Raspberry Pi and/or Leap Motion project, part II on Tuesday from 9:30am to 12:00pm to learn how to start a project with the Raspberry Pi and Leap Motion. In the afternoon, you can still join a project and create your own project with the help of experts on Raspberry Pi, Leap Motion and other boards.  At the Oracle booth, Java experts will be available  to answer your  questions and demo the new features of the Java Platform, including Java Embedded, JavaFX, Java SE and Java EE. This year, the chess game that was first demoed at JavaOne keynotes last September will be showcased at Devoxx.  Duke is coming to Devoxx this year. You can get your picture taken with Duke on Tuesday, Wednesday and Thursday (Nov. 12-14) from 12:00 to 18:00 Beer bash will be Tuesday from 17:30-19:30 and Wednesday/Thursday from 18:00 to 20:00 at the booth. Oracle is raffling off five Raspberry Pi's and a number of books every day. Make sure to stop by and get your badge scanned to enter the raffle. Raffles are Tuesday at 19:15 and Wednesday/Thursday at 19:45 at the Oracle booth.  The main conference sessions from Oracle Java experts are:  Wednesday 13 November Beyond Beauty: JavaFX, Parallax, Touch, Raspberry Pi, Gyroscopes, and Much More Angela Caicedo, Senior Member, Technical Staff, Oracle Room 7, 12:00–13:00 Lambda: A Peek Under the Hood, Brian Goetz, Software Architect, Oracle Room 8, 12:00–13:00 In Full Flow: Java 8 Lambdas in the Stream, Paul Sandoz, Software Developer, Oracle Room 8, 14:00–15:00 The Modular Java Platform and Project Jigsaw, Mark Reinhold, Chief Architect, Java Platform Group, Oracle, Room 8, 15:10–16:10 The Curious Case of JavaScript on the JVM, Attila Szegedi, Principal Member, Technical Staff, Oracle, Room 5, 16:40–17:40 Is It a Car? Is It a Computer? No, It’s a Raspberry Pi JavaFX Informatics System. Simon Ritter, Principal Technology Evangelist, Oracle Room 7, 16:40–17:40 Thursday 14 November Java EE 7: What’s New in the Java EE Platform Linda DeMichiel, Consulting Member, Technical Staff, Oracle, Room 8, 10:50–11:50 Java Microbenchmark Harness: The Lesser of the Two Evils, Aleksey Shipilev, Principal Member, Technical Staff, Oracle. Room 6, 14:00–15:00 Practical Restful Persistence, Shaun Smith, Senior Principal Product Manager, Oracle Room 8, 17:50–18:50 Friday 15 November Avatar.js, Server-Side JavaScript on the Java Platform, Jean-Francois Denise, Software Developer, Oracle Room 8, 11:50–12:50

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• Java Spotlight Episode 56: Stephan Jenssen, Java Champion, on Devoxx and Parleys

  - by Roger Brinkley

  Tweet Interview with Stephan Janssen, Java Champion, on Devoxx and Parleys Joining us this week on the Java All Star Developer Panel are Dalibor Topic, Java Free and Open Source Software Ambassador and Alexis Moussine-Pouchkine, Java EE Developer Advocate. Right-click or Control-click to download this MP3 file. You can also subscribe to the Java Spotlight Podcast Feed to get the latest podcast automatically. If you use iTunes you can open iTunes and subscribe with this link: Java Spotlight Podcast in iTunes. Show Notes News Devoxx Live Recording of the Java Spotlight Podcast. Come be part of the live recording. November 18, 10:45am in BOF 1 room next to the info desk Wanted: Java Code Brainteasers Adopt a JSR Flash to Focus on PC Browsing and Mobile Apps; Adobe to More Aggressively Contribute to HTML5 First binary snapshots of Project Lambda are available JSF 2.2 recent progress - Early Draft Latest OEPE (11.1.1.8) - Eclipse 3.7.1-based  Events Nov 14-18 Devoxx, Antwerp Nov 15-17, DOAG, Nuremberg, Germany Nov 22-25, OTN Developer Days in the Nordics Nov 22-23, Goto Conference, Prague Dec 6-8, Java One Brazil, Sao Paulo Feature interview Stephan Janssen is a serial entrepreneur that has founded several successful organizations such as the Belgian Java User Group (BeJUG) in 1996, JCS Int. in 1998, JavaPolis in 2002 and now Parleys.com in 2006. He has been using Java since its early releases in 1995 with experience of developing and implementing real world Java solutions in the finance and manufacturing industries. Today Stephan is the CTO of the Java Competence Center at RealDolmen. He was selected by BEA Systems as the first European (independent) BEA Technical Director. He has also been recognized by the Server Side as one of the 54 Who is Who in Enterprise Java 2004. Sun has recognized in 2005 his efforts for the Java Community and has engaged him in the Java Champion project. He has spoken at numerous Java and JUG conferences around the world. Mail Bag What's Cool Increased interest in Mobile and Embedded topics, on the heels of the JavaOne announcements. Speaking engagements, etc PodFodder: John Duimovich on IBM & OpenJDK at JavaOne 2011 Oracle Releases Oracle Solaris 11, the First Cloud OS Show Transcripts Transcript for this show is available here when available.

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• Devoxx!!

  - by Yolande

  0 0 1 350 2000 Oracle Corporation 16 4 2346 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;}  Announcing Devoxx London! Taking place on  March 26th and 27th, 2013 right before Devoxx  France on March 28th and 29th, this will be the first  edition of Devoxx UK!. The call for papers begins  on December 1st for Devoxx in London and Paris.  Speakers will be able to present at the two  conferences in the same week. Oracle committed  to fully sponsor the three Devoxx conferences in  2013 with a platinum sponsorship. Over 5,000 developers are expected to attend those conferences. Five dancing NAO robots welcomed attendees at the keynote. Stephan Janssen offers the JUGs to replicate Devoxx4kids workshops using his content and web infrastructure.  He recommended organizing kid events because “the workshops were really fun and such rewarding experience.” Stephan also announced the redesign of Parleys with Html 5 and GlassFish. Friendlier to speakers, they will be able to post their slides online before their talks and then sync the talk's sound track with the slides. Nandini Ramani, VP of product development explained in her keynote address the growing role of Java from enterprise application development to cloud computing to embedded machine-to-machines systems. “Java continues to drive the applications and devices that enrich our interactivity with the world around us” she said. The Java platform has expanded its reach with the OS X and Linux ARM support on Java SE and with two new releases, Java SE embedded and Java embedded Suite 7.0 middleware platform.  Coming up next year is JDK 8, which will include Project Lambda, Project Nashorn and more. As part of that release, JavaFX will offer 3D and third-party component integration. At Devoxx, the slick and interactive schedules were designed with JavaFX. The earliest version of the Java EE 7 SDK is available for download and has WebSocket support, improved JSON support and more.  Stephen Chin arrived on stage with his bike, ending his European NightHacking tour. Check the hacking sessions online here

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• TechCast Live: "Java and Oracle, One Year Later" Replay Now Available

  - by Justin Kestelyn

  Earlier this week I had the opportunity to chat with Ajay Patel, Oracle's VP leading the Java Evangelist team, about "the state of the union" wrt Oracle and Java. Take a look: And here are some choice quotes, some paraphrased, as helpfully transcribed by Java evangelist Terrence Barr: "One key thing we have learned ... Java is not just a platform, it is also an ecosystem, and you can't have an ecosystem without a community." "The objectives, strategically [for Java at Oracle] have been pretty clear: How do we drive adoption, how do we build a larger, stronger developer community, how do we really make the platform much more competitive." "It's about transparency, involvement. IBM, RedHat, Apple have all agreed to working with us to make OpenJDK the best platform for open source development ... it is a sign that the community has been waiting to move the Java platform forward." "It's not just about Oracle anymore, it's about Java, the technology, the community, the developer base, and how we work with them to move the innovation forward." "Java is strategic to Oracle, and the community is strategic for Java to be successful ... it is critical to our business." On JavaFX 2.0: "... is coming to beta soon, with a release planned in second half [of 2011] ... will give you a new, high-performance graphics engine, the new API for JavaFX ... you will see a very strong, relevant platform for levering rich media platforms." On the JDK and SE: "... aggressively moving forward, JDK 7 is now code complete ... looking good for getting JDK 7 out by summer as we promised. Started work on JDK 8, Jigsaw and Lambda are moving along nicely, on track for JDK 8 release next year ... good progress." On Java EE and Glassfish: "... Very excited to have Glassfish 3.1 released, with clustering and management capabilities ... working with the JCP to shortly submit a number of JSRs for Java EE 7 ... You'll see Java EE 7 becoming the platform for cloud-based development." "You will see Oracle continue to step up to this role of Java steward, making sure that the language, the technology, the platform ... is competitive, relevant, and widely adopted." Making progress!

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• Is 2 lines of push/pop code for each pre-draw-state too many?

  - by Griffin

  I'm trying to simplify vector graphics management in XNA; currently by incorporating state preservation. 2X lines of push/pop code for X states feels like too many, and it just feels wrong to have 2 lines of code that look identical except for one being push() and the other being pop(). The goal is to eradicate this repetitiveness,and I hoped to do so by creating an interface in which a client can give class/struct refs in which he wants restored after the rendering calls. Also note that many beginner-programmers will be using this, so forcing lambda expressions or other advanced C# features to be used in client code is not a good idea. I attempted to accomplish my goal by using Daniel Earwicker's Ptr class: public class Ptr<T> { Func<T> getter; Action<T> setter; public Ptr(Func<T> g, Action<T> s) { getter = g; setter = s; } public T Deref { get { return getter(); } set { setter(value); } } } an extension method: //doesn't work for structs since this is just syntatic sugar public static Ptr<T> GetPtr <T> (this T obj) { return new Ptr<T>( ()=> obj, v=> obj=v ); } and a Push Function: //returns a Pop Action for later calling public static Action Push <T> (ref T structure) where T: struct { T pushedValue = structure; //copies the struct data Ptr<T> p = structure.GetPtr(); return new Action( ()=> {p.Deref = pushedValue;} ); } However this doesn't work as stated in the code. How might I accomplish my goal? Example of code to be refactored: protected override void RenderLocally (GraphicsDevice device) { if (!(bool)isCompiled) {Compile();} //TODO: make sure state settings don't implicitly delete any buffers/resources RasterizerState oldRasterState = device.RasterizerState; DepthFormat oldFormat = device.PresentationParameters.DepthStencilFormat; DepthStencilState oldBufferState = device.DepthStencilState; { //Rendering code } device.RasterizerState = oldRasterState; device.DepthStencilState = oldBufferState; device.PresentationParameters.DepthStencilFormat = oldFormat; }

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• Why would I learn C++11, having known C and C++?

  - by Shahbaz

  I am a programmer in C and C++, although I don't stick to either language and write a mixture of the two. Sometimes having code in classes, possibly with operator overloading, or templates and the oh so great STL is obviously a better way. Sometimes use of a simple C function pointer is much much more readable and clear. So I find beauty and practicality in both languages. I don't want to get into the discussion of "If you mix them and compile with a C++ compiler, it's not a mix anymore, it's all C++" I think we all understand what I mean by mixing them. Also, I don't want to talk about C vs C++, this question is all about C++11. C++11 introduces what I think are significant changes to how C++ works, but it has introduced many special cases that change how different features behave in different circumstances, placing restrictions on multiple inheritance, adding lambda functions, etc. I know that at some point in the future, when you say C++ everyone would assume C++11. Much like when you say C nowadays, you most probably mean C99. That makes me consider learning C++11. After all, if I want to continue writing code in C++, I may at some point need to start using those features simply because my colleagues have. Take C for example. After so many years, there are still many people learning and writing code in C. Why? Because the language is good. What good means is that, it follows many of the rules to create a good programming language. So besides being powerful (which easy or hard, almost all programming languages are), C is regular and has few exceptions, if any. C++11 however, I don't think so. I'm not sure that the changes introduced in C++11 are making the language better. So the question is: Why would I learn C++11? Update: My original question in short was: "I like C++, but the new C++11 doesn't look good because of this and this and this. However, deep down something tells me I need to learn it. So, I asked this question here so that someone would help convince me to learn it." However, the zealous people here can't tolerate pointing out a flaw in their language and were not at all constructive in this manner. After the moderator edited the question, it became more like a "So, how about this new C++11?" which was not at all my question. Therefore, in a day or too I am going to delete this question if no one comes up with an actual convincing argument. P.S. If you are interested in knowing what flaws I was talking about, you can edit my question and see the previous edits.

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• LINQ to Twitter v2.1.09 Released

  - by Joe Mayo

  Originally posted on: http://geekswithblogs.net/WinAZ/archive/2013/10/15/linq-to-twitter-v2.1.09-released.aspxToday, I released LINQ to Twitter v2.1.09. Here are important new changes. Bug Fixes This is primarily a bug fix release. Most notably, there were authentication problems in WinRT apps. This is now fixed. New Features One new feature is the addition of ApplicationOnlyAuthentication for WinRT. It is fully async.  Here’s how it works: var auth = new WinRtApplicationOnlyAuthorizer { Credentials = new InMemoryCredentials { ConsumerKey = "", ConsumerSecret = "" } }; if (auth == null || !auth.IsAuthorized) { await auth.AuthorizeAsync(); } var twitterCtx = new TwitterContext(auth); (from search in twitterCtx.Search where search.Type == SearchType.Search && search.Query == SearchTextBox.Text select search) .MaterializedAsyncCallback( async response => await Dispatcher.RunAsync( CoreDispatcherPriority.Normal, async () => { Search searchResponse = response.State.Single(); string message = string.Format( "Search returned {0} statuses", searchResponse.Statuses.Count); await new MessageDialog(message, "Search Complete").ShowAsync(); })); It’s called the WinRtApplicationOnlyAuthorizer. You only need two tokens, ConsumerKey and ConsumerSecret, which come from your Twitter API application settings page. Note: You need a Twitter Application, which you can create at https://dev.twitter.com/. The MaterializedAsyncCallback materializes your query and handles the response. I put everything together in a lambda for demonstration purposes, but you can always replace the callback with a handler of type Action<TwitterAsyncResponse<IEnumerable<T>>>, where T is Search for this example. On the Horizon The next version of LINQ to Twitter is in development. I discussed it at LINQ to Twitter Async. This isn’t complete, but you can download the source code at the LINQ to Twitter site on CodePlex. I’ve competed all the spikes for what I thought would be the hard parts and now have prototypes of queries and commands working. This would be a good time to provide feedback if there are features in the current version that you think could be improved. The current driving forces for the next version will be async and PCL.   @JoeMayo

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• ??????????????? -Oracle ACE ????????

  - by OTN-J Master

  ??????????????????????Oracle ACE??2014?6???????Oracle ACE?15????????Oracle ACE??????????????????????????????????? ????????????OK???·?????????????????????? Oracle ACE???????Oracle ACE?????????? (OTN??????) OTN ????????Oracle ACE???????????????¦?? ???????????????????????????????????????????????????????????????????????????????????????????????????????????????????? Japan Oracle User Group (JPOUG) ??????????????9?????????????????????????????????Oracle Database 12c?????????????????????????????????????????????????????AWS??????????????????????????????????????????????????????????????????????????????????????????????????JPOUG ???????????????????????????????????????????????????????????????Blog??????????????Oracle ACE??????????Oracle ACE??????????????????????????????????Oracle ACE?????(http://www.oracle.com/technetwork/jp/community/index-098108-ja.html)??????????????????????????????????????????????????????????????????????????????????????????????????????????????(JPOUG)????????Web???Blog????????????????¦?? ???????Oracle9i SE??Oracle11g EE(RAC????)??????????????????????????????????????????????????(?)Oracle Exadata????????????????(???????????????”???”????????????????)?Oracle Database 12c?Adaptive Plan?????Adaptive Join Method??????????????????????????5????SQL???10???????????????????????????????????????????????????????????????????Adaptive plan????????????????????Oracle ACE??????????JPOUG (Japan Oracle Users Group)??????Blog???????????????????????????????????????????Oracle ACE??????????Oracle ACE??????Blog??????????????????????(?????????????????????????????????????)?????????????????????????????????????????Oracle ACE??????????????????????????????????????????????????????????????¦?? ?????????WebLogic Server ??????? Oracle Fusion Middleware ??????????????????Oracle ACE ????????WebLogic Server ??????????????JJUG (??Java????????) ???????????????????Java SE 8 ????????????????????????????????????? Lambda ????????????????????????? WebLogic Server ?????????????????????????????????????Oracle ACE??????????ACE Associate ?????????????????????????????????????????????????????? ACE ?????????(?)??? Normal 0 0 2 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0mm 5.4pt 0mm 5.4pt; mso-para-margin:0mm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.5pt; mso-bidi-font-size:11.0pt; font-family:"Century","serif"; mso-ascii-font-family:Century; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Century; mso-hansi-theme-font:minor-latin; mso-font-kerning:1.0pt;}  

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• Do You Really Know Your Programming Languages?

  - by Kristopher Johnson

  I am often amazed at how little some of my colleagues know or care about their craft. Something that constantly frustrates me is that people don't want to learn any more than they need to about the programming languages they use every day. Many programmers seem content to learn some pidgin sub-dialect, and stick with that. If they see a keyword or construct that they aren't familiar with, they'll complain that the code is "tricky." What would you think of a civil engineer who shied away from calculus because it had "all those tricky math symbols?" I'm not suggesting that we all need to become "language lawyers." But if you make your living as a programmer, and claim to be a competent user of language X, then I think at a minimum you should know the following: Do you know the keywords of the language and what they do? What are the valid syntactic forms? How are memory, files, and other operating system resources managed? Where is the official language specification and library reference for the language? The last one is the one that really gets me. Many programmers seem to have no idea that there is a "specification" or "standard" for any particular language. I still talk to people who think that Microsoft invented C++, and that if a program doesn't compile under VC6, it's not a valid C++ program. Programmers these days have it easy when it comes to obtaining specs. Newer languages like C#, Java, Python, Ruby, etc. all have their documentation available for free from the vendors' web sites. Older languages and platforms often have standards controlled by standards bodies that demand payment for specs, but even that shouldn't be a deterrent: the C++ standard is available from ISO for $30 (and why am I the only person I know who has a copy?). Programming is hard enough even when you do know the language. If you don't, I don't see how you have a chance. What do the rest of you think? Am I right, or should we all be content with the typical level of programming language expertise? Update: Several great comments here. Thanks. A couple of people hit on something that I didn't think about: What really irks me is not the lack of knowledge, but the lack of curiosity and willingness to learn. It seems some people don't have any time to hone their craft, but they have plenty of time to write lots of bad code. And I don't expect people to be able to recite a list of keywords or EBNF expressions, but I do expect that when they see some code, they should have some inkling of what it does. Few people have complete knowledge of every dark corner of their language or platform, but everyone should at least know enough that when they see something unfamiliar, they will know how to get whatever additional information they need to understand it.

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• Routes on a sphere surface - Find geodesic?

  - by CaNNaDaRk

  I'm working with some friends on a browser based game where people can move on a 2D map. It's been almost 7 years and still people play this game so we are thinking of a way to give them something new. Since then the game map was a limited plane and people could move from (0, 0) to (MAX_X, MAX_Y) in quantized X and Y increments (just imagine it as a big chessboard). We believe it's time to give it another dimension so, just a couple of weeks ago, we began to wonder how the game could look with other mappings: Unlimited plane with continous movement: this could be a step forward but still i'm not convinced. Toroidal World (continous or quantized movement): sincerely I worked with torus before but this time I want something more... Spherical world with continous movement: this would be great! What we want Users browsers are given a list of coordinates like (latitude, longitude) for each object on the spherical surface map; browsers must then show this in user's screen rendering them inside a web element (canvas maybe? this is not a problem). When people click on the plane we convert the (mouseX, mouseY) to (lat, lng) and send it to the server which has to compute a route between current user's position to the clicked point. What we have We began writing a Java library with many useful maths to work with Rotation Matrices, Quaternions, Euler Angles, Translations, etc. We put it all together and created a program that generates sphere points, renders them and show them to the user inside a JPanel. We managed to catch clicks and translate them to spherical coords and to provide some other useful features like view rotation, scale, translation etc. What we have now is like a little (very little indeed) engine that simulates client and server interaction. Client side shows points on the screen and catches other interactions, server side renders the view and does other calculus like interpolating the route between current position and clicked point. Where is the problem? Obviously we want to have the shortest path to interpolate between the two route points. We use quaternions to interpolate between two points on the surface of the sphere and this seemed to work fine until i noticed that we weren't getting the shortest path on the sphere surface: We though the problem was that the route is calculated as the sum of two rotations about X and Y axis. So we changed the way we calculate the destination quaternion: We get the third angle (the first is latitude, the second is longitude, the third is the rotation about the vector which points toward our current position) which we called orientation. Now that we have the "orientation" angle we rotate Z axis and then use the result vector as the rotation axis for the destination quaternion (you can see the rotation axis in grey): What we got is the correct route (you can see it lays on a great circle), but we get to this ONLY if the starting route point is at latitude, longitude (0, 0) which means the starting vector is (sphereRadius, 0, 0). With the previous version (image 1) we don't get a good result even when startin point is 0, 0, so i think we're moving towards a solution, but the procedure we follow to get this route is a little "strange" maybe? In the following image you get a view of the problem we get when starting point is not (0, 0), as you can see starting point is not the (sphereRadius, 0, 0) vector, and as you can see the destination point (which is correctly drawn!) is not on the route. The magenta point (the one which lays on the route) is the route's ending point rotated about the center of the sphere of (-startLatitude, 0, -startLongitude). This means that if i calculate a rotation matrix and apply it to every point on the route maybe i'll get the real route, but I start to think that there's a better way to do this. Maybe I should try to get the plane through the center of the sphere and the route points, intersect it with the sphere and get the geodesic? But how? Sorry for being way too verbose and maybe for incorrect English but this thing is blowing my mind! EDIT: This code version is related to the first image: public void setRouteStart(double lat, double lng) { EulerAngles tmp = new EulerAngles ( Math.toRadians(lat), 0, -Math.toRadians(lng)); //set route start Quaternion qtStart.setInertialToObject(tmp); //do other stuff like drawing start point... } public void impostaDestinazione(double lat, double lng) { EulerAngles tmp = new AngoliEulero( Math.toRadians(lat), 0, -Math.toRadians(lng)); qtEnd.setInertialToObject(tmp); //do other stuff like drawing dest point... } public V3D interpolate(double totalTime, double t) { double _t = t/totalTime; Quaternion q = Quaternion.Slerp(qtStart, qtEnd, _t); RotationMatrix.inertialQuatToIObject(q); V3D p = matInt.inertialToObject(V3D.Xaxis.scale(sphereRadius)); //other stuff, like drawing point ... return p; } //mostly taken from a book! public static Quaternion Slerp(Quaternion q0, Quaternion q1, double t) { double cosO = q0.dot(q1); double q1w = q1.w; double q1x = q1.x; double q1y = q1.y; double q1z = q1.z; if (cosO < 0.0f) { q1w = -q1w; q1x = -q1x; q1y = -q1y; q1z = -q1z; cosO = -cosO; } double sinO = Math.sqrt(1.0f - cosO*cosO); double O = Math.atan2(sinO, cosO); double oneOverSinO = 1.0f / senoOmega; k0 = Math.sin((1.0f - t) * O) * oneOverSinO; k1 = Math.sin(t * O) * oneOverSinO; // Interpolate return new Quaternion( k0*q0.w + k1*q1w, k0*q0.x + k1*q1x, k0*q0.y + k1*q1y, k0*q0.z + k1*q1z ); } A little dump of what i get (again check image 1): Route info: Sphere radius and center: 200,000, (0.0, 0.0, 0.0) Route start: lat 0,000 °, lng 0,000 ° @v: (200,000, 0,000, 0,000), |v| = 200,000 Route end: lat 30,000 °, lng 30,000 ° @v: (150,000, 86,603, 100,000), |v| = 200,000 Qt dump: (w, x, y, z), rot. angle°, (x, y, z) rot. axis Qt start: (1,000, 0,000, -0,000, 0,000); 0,000 °; (1,000, 0,000, 0,000) Qt end: (0,933, 0,067, -0,250, 0,250); 42,181 °; (0,186, -0,695, 0,695) Route start: lat 30,000 °, lng 10,000 ° @v: (170,574, 30,077, 100,000), |v| = 200,000 Route end: lat 80,000 °, lng -50,000 ° @v: (22,324, -26,604, 196,962), |v| = 200,000 Qt dump: (w, x, y, z), rot. angle°, (x, y, z) rot. axis Qt start: (0,962, 0,023, -0,258, 0,084); 31,586 °; (0,083, -0,947, 0,309) Qt end: (0,694, -0,272, -0,583, -0,324); 92,062 °; (-0,377, -0,809, -0,450)

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• Emacs 24.1: How do I restore i-search Ctrl-Y behavior from older versions?

  - by Eric

  In emacs 24.1, when you do Ctrl-Y in an interactive search, it yanks the kill buffer into the search string ("it pastes the clipboard contents" in any-other-app's language) and tries to match it. In the last 20 versions or so, pressing Ctrl-Y matches the rest of the current line. I have two very common use cases: Match this line, revert the buffer, and search for the line (less often:) Where else is this text in the buffer? I tried modifying /lisp/isearch.el, switching the bindings for isearch-yank-line (which I want) and isearch-yank-kill (which I'm fine binding to the ridiculous \M-s\C-e key sequence). But I don't think this file even gets picked up. But I don't think this file even gets loaded. If I explicitly load it, I still get the 24.1 behavior. Here's my change: (add-hook 'isearch-mode-hook (lambda () (define-key isearch-mode-map "\C-y" 'isearch-yank-line) (define-key isearch-mode-map "\M-s\C-e" 'isearch-yank-kill) )) No change in the behavior. I even tried hacking isearch.el, still no change. This is on Windows btw, but I suspect it doesn't matter. Could someone tell me how I can restore the old binding?

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• New features of C# 4.0

  This article covers New features of C# 4.0. Article has been divided into below sections. Introduction. Dynamic Lookup. Named and Optional Arguments. Features for COM interop. Variance. Relationship with Visual Basic. Resources. Other interested readings… 22 New Features of Visual Studio 2008 for .NET Professionals 50 New Features of SQL Server 2008 IIS 7.0 New features Introduction It is now close to a year since Microsoft Visual C# 3.0 shipped as part of Visual Studio 2008. In the VS Managed Languages team we are hard at work on creating the next version of the language (with the unsurprising working title of C# 4.0), and this document is a first public description of the planned language features as we currently see them. Please be advised that all this is in early stages of production and is subject to change. Part of the reason for sharing our plans in public so early is precisely to get the kind of feedback that will cause us to improve the final product before it rolls out. Simultaneously with the publication of this whitepaper, a first public CTP (community technology preview) of Visual Studio 2010 is going out as a Virtual PC image for everyone to try. Please use it to play and experiment with the features, and let us know of any thoughts you have. We ask for your understanding and patience working with very early bits, where especially new or newly implemented features do not have the quality or stability of a final product. The aim of the CTP is not to give you a productive work environment but to give you the best possible impression of what we are working on for the next release. The CTP contains a number of walkthroughs, some of which highlight the new language features of C# 4.0. Those are excellent for getting a hands-on guided tour through the details of some common scenarios for the features. You may consider this whitepaper a companion document to these walkthroughs, complementing them with a focus on the overall language features and how they work, as opposed to the specifics of the concrete scenarios. C# 4.0 The major theme for C# 4.0 is dynamic programming. Increasingly, objects are “dynamic” in the sense that their structure and behavior is not captured by a static type, or at least not one that the compiler knows about when compiling your program. Some examples include a. objects from dynamic programming languages, such as Python or Ruby b. COM objects accessed through IDispatch c. ordinary .NET types accessed through reflection d. objects with changing structure, such as HTML DOM objects While C# remains a statically typed language, we aim to vastly improve the interaction with such objects. A secondary theme is co-evolution with Visual Basic. Going forward we will aim to maintain the individual character of each language, but at the same time important new features should be introduced in both languages at the same time. They should be differentiated more by style and feel than by feature set. The new features in C# 4.0 fall into four groups: Dynamic lookup Dynamic lookup allows you to write method, operator and indexer calls, property and field accesses, and even object invocations which bypass the C# static type checking and instead gets resolved at runtime. Named and optional parameters Parameters in C# can now be specified as optional by providing a default value for them in a member declaration. When the member is invoked, optional arguments can be omitted. Furthermore, any argument can be passed by parameter name instead of position. COM specific interop features Dynamic lookup as well as named and optional parameters both help making programming against COM less painful than today. On top of that, however, we are adding a number of other small features that further improve the interop experience. Variance It used to be that an IEnumerable<string> wasn’t an IEnumerable<object>. Now it is – C# embraces type safe “co-and contravariance” and common BCL types are updated to take advantage of that. Dynamic Lookup Dynamic lookup allows you a unified approach to invoking things dynamically. With dynamic lookup, when you have an object in your hand you do not need to worry about whether it comes from COM, IronPython, the HTML DOM or reflection; you just apply operations to it and leave it to the runtime to figure out what exactly those operations mean for that particular object. This affords you enormous flexibility, and can greatly simplify your code, but it does come with a significant drawback: Static typing is not maintained for these operations. A dynamic object is assumed at compile time to support any operation, and only at runtime will you get an error if it wasn’t so. Oftentimes this will be no loss, because the object wouldn’t have a static type anyway, in other cases it is a tradeoff between brevity and safety. In order to facilitate this tradeoff, it is a design goal of C# to allow you to opt in or opt out of dynamic behavior on every single call. The dynamic type C# 4.0 introduces a new static type called dynamic. When you have an object of type dynamic you can “do things to it” that are resolved only at runtime: dynamic d = GetDynamicObject(…); d.M(7); The C# compiler allows you to call a method with any name and any arguments on d because it is of type dynamic. At runtime the actual object that d refers to will be examined to determine what it means to “call M with an int” on it. The type dynamic can be thought of as a special version of the type object, which signals that the object can be used dynamically. It is easy to opt in or out of dynamic behavior: any object can be implicitly converted to dynamic, “suspending belief” until runtime. Conversely, there is an “assignment conversion” from dynamic to any other type, which allows implicit conversion in assignment-like constructs: dynamic d = 7; // implicit conversion int i = d; // assignment conversion Dynamic operations Not only method calls, but also field and property accesses, indexer and operator calls and even delegate invocations can be dispatched dynamically: dynamic d = GetDynamicObject(…); d.M(7); // calling methods d.f = d.P; // getting and settings fields and properties d[“one”] = d[“two”]; // getting and setting thorugh indexers int i = d + 3; // calling operators string s = d(5,7); // invoking as a delegate The role of the C# compiler here is simply to package up the necessary information about “what is being done to d”, so that the runtime can pick it up and determine what the exact meaning of it is given an actual object d. Think of it as deferring part of the compiler’s job to runtime. The result of any dynamic operation is itself of type dynamic. Runtime lookup At runtime a dynamic operation is dispatched according to the nature of its target object d: COM objects If d is a COM object, the operation is dispatched dynamically through COM IDispatch. This allows calling to COM types that don’t have a Primary Interop Assembly (PIA), and relying on COM features that don’t have a counterpart in C#, such as indexed properties and default properties. Dynamic objects If d implements the interface IDynamicObject d itself is asked to perform the operation. Thus by implementing IDynamicObject a type can completely redefine the meaning of dynamic operations. This is used intensively by dynamic languages such as IronPython and IronRuby to implement their own dynamic object models. It will also be used by APIs, e.g. by the HTML DOM to allow direct access to the object’s properties using property syntax. Plain objects Otherwise d is a standard .NET object, and the operation will be dispatched using reflection on its type and a C# “runtime binder” which implements C#’s lookup and overload resolution semantics at runtime. This is essentially a part of the C# compiler running as a runtime component to “finish the work” on dynamic operations that was deferred by the static compiler. Example Assume the following code: dynamic d1 = new Foo(); dynamic d2 = new Bar(); string s; d1.M(s, d2, 3, null); Because the receiver of the call to M is dynamic, the C# compiler does not try to resolve the meaning of the call. Instead it stashes away information for the runtime about the call. This information (often referred to as the “payload”) is essentially equivalent to: “Perform an instance method call of M with the following arguments: 1. a string 2. a dynamic 3. a literal int 3 4. a literal object null” At runtime, assume that the actual type Foo of d1 is not a COM type and does not implement IDynamicObject. In this case the C# runtime binder picks up to finish the overload resolution job based on runtime type information, proceeding as follows: 1. Reflection is used to obtain the actual runtime types of the two objects, d1 and d2, that did not have a static type (or rather had the static type dynamic). The result is Foo for d1 and Bar for d2. 2. Method lookup and overload resolution is performed on the type Foo with the call M(string,Bar,3,null) using ordinary C# semantics. 3. If the method is found it is invoked; otherwise a runtime exception is thrown. Overload resolution with dynamic arguments Even if the receiver of a method call is of a static type, overload resolution can still happen at runtime. This can happen if one or more of the arguments have the type dynamic: Foo foo = new Foo(); dynamic d = new Bar(); var result = foo.M(d); The C# runtime binder will choose between the statically known overloads of M on Foo, based on the runtime type of d, namely Bar. The result is again of type dynamic. The Dynamic Language Runtime An important component in the underlying implementation of dynamic lookup is the Dynamic Language Runtime (DLR), which is a new API in .NET 4.0. The DLR provides most of the infrastructure behind not only C# dynamic lookup but also the implementation of several dynamic programming languages on .NET, such as IronPython and IronRuby. Through this common infrastructure a high degree of interoperability is ensured, but just as importantly the DLR provides excellent caching mechanisms which serve to greatly enhance the efficiency of runtime dispatch. To the user of dynamic lookup in C#, the DLR is invisible except for the improved efficiency. However, if you want to implement your own dynamically dispatched objects, the IDynamicObject interface allows you to interoperate with the DLR and plug in your own behavior. This is a rather advanced task, which requires you to understand a good deal more about the inner workings of the DLR. For API writers, however, it can definitely be worth the trouble in order to vastly improve the usability of e.g. a library representing an inherently dynamic domain. Open issues There are a few limitations and things that might work differently than you would expect. · The DLR allows objects to be created from objects that represent classes. However, the current implementation of C# doesn’t have syntax to support this. · Dynamic lookup will not be able to find extension methods. Whether extension methods apply or not depends on the static context of the call (i.e. which using clauses occur), and this context information is not currently kept as part of the payload. · Anonymous functions (i.e. lambda expressions) cannot appear as arguments to a dynamic method call. The compiler cannot bind (i.e. “understand”) an anonymous function without knowing what type it is converted to. One consequence of these limitations is that you cannot easily use LINQ queries over dynamic objects: dynamic collection = …; var result = collection.Select(e => e + 5); If the Select method is an extension method, dynamic lookup will not find it. Even if it is an instance method, the above does not compile, because a lambda expression cannot be passed as an argument to a dynamic operation. There are no plans to address these limitations in C# 4.0. Named and Optional Arguments Named and optional parameters are really two distinct features, but are often useful together. Optional parameters allow you to omit arguments to member invocations, whereas named arguments is a way to provide an argument using the name of the corresponding parameter instead of relying on its position in the parameter list. Some APIs, most notably COM interfaces such as the Office automation APIs, are written specifically with named and optional parameters in mind. Up until now it has been very painful to call into these APIs from C#, with sometimes as many as thirty arguments having to be explicitly passed, most of which have reasonable default values and could be omitted. Even in APIs for .NET however you sometimes find yourself compelled to write many overloads of a method with different combinations of parameters, in order to provide maximum usability to the callers. Optional parameters are a useful alternative for these situations. Optional parameters A parameter is declared optional simply by providing a default value for it: public void M(int x, int y = 5, int z = 7); Here y and z are optional parameters and can be omitted in calls: M(1, 2, 3); // ordinary call of M M(1, 2); // omitting z – equivalent to M(1, 2, 7) M(1); // omitting both y and z – equivalent to M(1, 5, 7) Named and optional arguments C# 4.0 does not permit you to omit arguments between commas as in M(1,,3). This could lead to highly unreadable comma-counting code. Instead any argument can be passed by name. Thus if you want to omit only y from a call of M you can write: M(1, z: 3); // passing z by name or M(x: 1, z: 3); // passing both x and z by name or even M(z: 3, x: 1); // reversing the order of arguments All forms are equivalent, except that arguments are always evaluated in the order they appear, so in the last example the 3 is evaluated before the 1. Optional and named arguments can be used not only with methods but also with indexers and constructors. Overload resolution Named and optional arguments affect overload resolution, but the changes are relatively simple: A signature is applicable if all its parameters are either optional or have exactly one corresponding argument (by name or position) in the call which is convertible to the parameter type. Betterness rules on conversions are only applied for arguments that are explicitly given – omitted optional arguments are ignored for betterness purposes. If two signatures are equally good, one that does not omit optional parameters is preferred. M(string s, int i = 1); M(object o); M(int i, string s = “Hello”); M(int i); M(5); Given these overloads, we can see the working of the rules above. M(string,int) is not applicable because 5 doesn’t convert to string. M(int,string) is applicable because its second parameter is optional, and so, obviously are M(object) and M(int). M(int,string) and M(int) are both better than M(object) because the conversion from 5 to int is better than the conversion from 5 to object. Finally M(int) is better than M(int,string) because no optional arguments are omitted. Thus the method that gets called is M(int). Features for COM interop Dynamic lookup as well as named and optional parameters greatly improve the experience of interoperating with COM APIs such as the Office Automation APIs. In order to remove even more of the speed bumps, a couple of small COM-specific features are also added to C# 4.0. Dynamic import Many COM methods accept and return variant types, which are represented in the PIAs as object. In the vast majority of cases, a programmer calling these methods already knows the static type of a returned object from context, but explicitly has to perform a cast on the returned value to make use of that knowledge. These casts are so common that they constitute a major nuisance. In order to facilitate a smoother experience, you can now choose to import these COM APIs in such a way that variants are instead represented using the type dynamic. In other words, from your point of view, COM signatures now have occurrences of dynamic instead of object in them. This means that you can easily access members directly off a returned object, or you can assign it to a strongly typed local variable without having to cast. To illustrate, you can now say excel.Cells[1, 1].Value = "Hello"; instead of ((Excel.Range)excel.Cells[1, 1]).Value2 = "Hello"; and Excel.Range range = excel.Cells[1, 1]; instead of Excel.Range range = (Excel.Range)excel.Cells[1, 1]; Compiling without PIAs Primary Interop Assemblies are large .NET assemblies generated from COM interfaces to facilitate strongly typed interoperability. They provide great support at design time, where your experience of the interop is as good as if the types where really defined in .NET. However, at runtime these large assemblies can easily bloat your program, and also cause versioning issues because they are distributed independently of your application. The no-PIA feature allows you to continue to use PIAs at design time without having them around at runtime. Instead, the C# compiler will bake the small part of the PIA that a program actually uses directly into its assembly. At runtime the PIA does not have to be loaded. Omitting ref Because of a different programming model, many COM APIs contain a lot of reference parameters. Contrary to refs in C#, these are typically not meant to mutate a passed-in argument for the subsequent benefit of the caller, but are simply another way of passing value parameters. It therefore seems unreasonable that a C# programmer should have to create temporary variables for all such ref parameters and pass these by reference. Instead, specifically for COM methods, the C# compiler will allow you to pass arguments by value to such a method, and will automatically generate temporary variables to hold the passed-in values, subsequently discarding these when the call returns. In this way the caller sees value semantics, and will not experience any side effects, but the called method still gets a reference. Open issues A few COM interface features still are not surfaced in C#. Most notably these include indexed properties and default properties. As mentioned above these will be respected if you access COM dynamically, but statically typed C# code will still not recognize them. There are currently no plans to address these remaining speed bumps in C# 4.0. Variance An aspect of generics that often comes across as surprising is that the following is illegal: IList<string> strings = new List<string>(); IList<object> objects = strings; The second assignment is disallowed because strings does not have the same element type as objects. There is a perfectly good reason for this. If it were allowed you could write: objects[0] = 5; string s = strings[0]; Allowing an int to be inserted into a list of strings and subsequently extracted as a string. This would be a breach of type safety. However, there are certain interfaces where the above cannot occur, notably where there is no way to insert an object into the collection. Such an interface is IEnumerable<T>. If instead you say: IEnumerable<object> objects = strings; There is no way we can put the wrong kind of thing into strings through objects, because objects doesn’t have a method that takes an element in. Variance is about allowing assignments such as this in cases where it is safe. The result is that a lot of situations that were previously surprising now just work. Covariance In .NET 4.0 the IEnumerable<T> interface will be declared in the following way: public interface IEnumerable<out T> : IEnumerable { IEnumerator<T> GetEnumerator(); } public interface IEnumerator<out T> : IEnumerator { bool MoveNext(); T Current { get; } } The “out” in these declarations signifies that the T can only occur in output position in the interface – the compiler will complain otherwise. In return for this restriction, the interface becomes “covariant” in T, which means that an IEnumerable<A> is considered an IEnumerable<B> if A has a reference conversion to B. As a result, any sequence of strings is also e.g. a sequence of objects. This is useful e.g. in many LINQ methods. Using the declarations above: var result = strings.Union(objects); // succeeds with an IEnumerable<object> This would previously have been disallowed, and you would have had to to some cumbersome wrapping to get the two sequences to have the same element type. Contravariance Type parameters can also have an “in” modifier, restricting them to occur only in input positions. An example is IComparer<T>: public interface IComparer<in T> { public int Compare(T left, T right); } The somewhat baffling result is that an IComparer<object> can in fact be considered an IComparer<string>! It makes sense when you think about it: If a comparer can compare any two objects, it can certainly also compare two strings. This property is referred to as contravariance. A generic type can have both in and out modifiers on its type parameters, as is the case with the Func<…> delegate types: public delegate TResult Func<in TArg, out TResult>(TArg arg); Obviously the argument only ever comes in, and the result only ever comes out. Therefore a Func<object,string> can in fact be used as a Func<string,object>. Limitations Variant type parameters can only be declared on interfaces and delegate types, due to a restriction in the CLR. Variance only applies when there is a reference conversion between the type arguments. For instance, an IEnumerable<int> is not an IEnumerable<object> because the conversion from int to object is a boxing conversion, not a reference conversion. Also please note that the CTP does not contain the new versions of the .NET types mentioned above. In order to experiment with variance you have to declare your own variant interfaces and delegate types. COM Example Here is a larger Office automation example that shows many of the new C# features in action. using System; using System.Diagnostics; using System.Linq; using Excel = Microsoft.Office.Interop.Excel; using Word = Microsoft.Office.Interop.Word; class Program { static void Main(string[] args) { var excel = new Excel.Application(); excel.Visible = true; excel.Workbooks.Add(); // optional arguments omitted excel.Cells[1, 1].Value = "Process Name"; // no casts; Value dynamically excel.Cells[1, 2].Value = "Memory Usage"; // accessed var processes = Process.GetProcesses() .OrderByDescending(p =&gt; p.WorkingSet) .Take(10); int i = 2; foreach (var p in processes) { excel.Cells[i, 1].Value = p.ProcessName; // no casts excel.Cells[i, 2].Value = p.WorkingSet; // no casts i++; } Excel.Range range = excel.Cells[1, 1]; // no casts Excel.Chart chart = excel.ActiveWorkbook.Charts. Add(After: excel.ActiveSheet); // named and optional arguments chart.ChartWizard( Source: range.CurrentRegion, Title: "Memory Usage in " + Environment.MachineName); //named+optional chart.ChartStyle = 45; chart.CopyPicture(Excel.XlPictureAppearance.xlScreen, Excel.XlCopyPictureFormat.xlBitmap, Excel.XlPictureAppearance.xlScreen); var word = new Word.Application(); word.Visible = true; word.Documents.Add(); // optional arguments word.Selection.Paste(); } } The code is much more terse and readable than the C# 3.0 counterpart. Note especially how the Value property is accessed dynamically. This is actually an indexed property, i.e. a property that takes an argument; something which C# does not understand. However the argument is optional. Since the access is dynamic, it goes through the runtime COM binder which knows to substitute the default value and call the indexed property. Thus, dynamic COM allows you to avoid accesses to the puzzling Value2 property of Excel ranges. Relationship with Visual Basic A number of the features introduced to C# 4.0 already exist or will be introduced in some form or other in Visual Basic: · Late binding in VB is similar in many ways to dynamic lookup in C#, and can be expected to make more use of the DLR in the future, leading to further parity with C#. · Named and optional arguments have been part of Visual Basic for a long time, and the C# version of the feature is explicitly engineered with maximal VB interoperability in mind. · NoPIA and variance are both being introduced to VB and C# at the same time. VB in turn is adding a number of features that have hitherto been a mainstay of C#. As a result future versions of C# and VB will have much better feature parity, for the benefit of everyone. Resources All available resources concerning C# 4.0 can be accessed through the C# Dev Center. Specifically, this white paper and other resources can be found at the Code Gallery site. Enjoy! span.fullpost {display:none;}

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• What is the best practice when coding math class/functions ?

  - by Isaac Clarke

  Introductory note : I voluntarily chose a wide subject. You know that quote about learning a cat to fish, that's it. I don't need an answer to my question, I need an explanation and advice. I know you guys are good at this ;) Hi guys, I'm currently implementing some algorithms into an existing program. Long story short, I created a new class, "Adder". An Adder is a member of another class representing the physical object actually doing the calculus , which calls adder.calc() with its parameters (merely a list of objects to do the maths on). To do these maths, I need some parameters, which do not exist outside of the class (but can be set, see below). They're neither config parameters nor members of other classes. These parameters are D1 and D2, distances, and three arrays of fixed size : alpha, beta, delta. I know some of you are more comfortable reading code than reading text so here you go : class Adder { public: Adder(); virtual Adder::~Adder(); void set( float d1, float d2 ); void set( float d1, float d2, int alpha[N_MAX], int beta[N_MAX], int delta[N_MAX] ); // Snipped prototypes float calc( List& ... ); // ... inline float get_d1() { return d1_ ;}; inline float get_d2() { return d2_ ;}; private: float d1_; float d2_; int alpha_[N_MAX]; // A #define N_MAX is done elsewhere int beta_[N_MAX]; int delta_[N_MAX]; }; Since this object is used as a member of another class, it is declared in a *.h : private: Adder adder_; By doing that, I couldn't initialize the arrays (alpha/beta/delta) directly in the constructor ( int T[3] = { 1, 2, 3 }; ), without having to iterate throughout the three arrays. I thought of putting them in static const, but I don't think that's the proper way of solving such problems. My second guess was to use the constructor to initialize the arrays Adder::Adder() { int alpha[N_MAX] = { 0, -60, -120, 180, 120, 60 }; int beta[N_MAX] = { 0, 0, 0, 0, 0, 0 }; int delta[N_MAX] = { 0, 0, 180, 180, 180, 0 }; set( 2.5, 0, alpha, beta, delta ); } void Adder::set( float d1, float d2 ) { if (d1 > 0) d1_ = d1; if (d2 > 0) d2_ = d2; } void Adder::set( float d1, float d2, int alpha[N_MAX], int beta[N_MAX], int delta[N_MAX] ) { set( d1, d2 ); for (int i = 0; i < N_MAX; ++i) { alpha_[i] = alpha[i]; beta_[i] = beta[i]; delta_[i] = delta[i]; } } My question is : Would it be better to use another function - init() - which would initialize arrays ? Or is there a better way of doing that ? My bonus question is : Did you see some mistakes or bad practice along the way ?

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• concurrency::accelerator_view

  - by Daniel Moth

  Overview We saw previously that accelerator represents a target for our C++ AMP computation or memory allocation and that there is a notion of a default accelerator. We ended that post by introducing how one can obtain accelerator_view objects from an accelerator object through the accelerator class's default_view property and the create_view method. The accelerator_view objects can be thought of as handles to an accelerator. You can also construct an accelerator_view given another accelerator_view (through the copy constructor or the assignment operator overload). Speaking of operator overloading, you can also compare (for equality and inequality) two accelerator_view objects between them to determine if they refer to the same underlying accelerator. We'll see later that when we use concurrency::array objects, the allocation of data takes place on an accelerator at array construction time, so there is a constructor overload that accepts an accelerator_view object. We'll also see later that a new concurrency::parallel_for_each function overload can take an accelerator_view object, so it knows on what target to execute the computation (represented by a lambda that the parallel_for_each also accepts). Beyond normal usage, accelerator_view is a quality of service concept that offers isolation to multiple "consumers" of an accelerator. If in your code you are accessing the accelerator from multiple threads (or, in general, from different parts of your app), then you'll want to create separate accelerator_view objects for each thread. flush, wait, and queuing_mode When you create an accelerator_view via the create_view method of the accelerator, you pass in an option of immediate or deferred, which are the two members of the queuing_mode enum. At any point you can access this value from the queuing_mode property of the accelerator_view. When the queuing_mode value is immediate (which is the default), any commands sent to the device such as kernel invocations and data transfers (e.g. parallel_for_each and copy, as we'll see in future posts), will get submitted as soon as the runtime sees fit (that is the definition of immediate). When the value of queuing_mode is deferred, the commands will be batched up. To send all buffered commands to the device for execution, there is a non-blocking flush method that you can call. If you wish to block until all the commands have been sent, there is a wait method you can call. Deferring is a more advanced scenario aimed at performance gains when you are submitting many device commands and you want to avoid the tiny overhead of flushing/submitting each command separately. Querying information Just like accelerator, accelerator_view exposes the is_debug and version properties. In fact, you can always access the accelerator object from the accelerator property on the accelerator_view class to access the accelerator interface we looked at previously. Interop with D3D (aka DX) In a later post I'll show an example of an app that uses C++ AMP to compute data that is used in pixel shaders. In those scenarios, you can benefit by integrating C++ AMP into your graphics pipeline and one of the building blocks for that is being able to use the same device context from both the compute kernel and the other shaders. You can do that by going from accelerator_view to device context (and vice versa), through part of our interop API in amp.h: *get_device, create_accelerator_view. More on those in a later post. Comments about this post by Daniel Moth welcome at the original blog.

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• Windows 8 Will be Here Tomorrow; but Should Silverlight be Gone Today?

  - by andrewbrust

  The software industry lives within an interesting paradox. IT in the enterprise moves slowly and cautiously, upgrading only when safe and necessary.  IT interests intentionally live in the past.  On the other hand, developers, and Independent Software Vendors (ISVs) not only want to use the latest and greatest technologies, but this constituency prides itself on gauging tech’s future, and basing its present-day strategy upon it.  Normally, we as an industry manage this paradox with a shrug of the shoulder and musings along the lines of “it takes all kinds.”  Different subcultures have different tendencies.  So be it. Microsoft, with its Windows operating system (OS), can’t take such a laissez-faire view of the world though.  Redmond relies on IT to deploy Windows and (at the very least) influence its procurement, but it also relies on developers to build software for Windows, especially software that has a dependency on features in new versions of the OS.  It must indulge and nourish developers’ fetish for an early birthing of the next generation of software, even as it acknowledges the IT reality that the next wave will arrive on-schedule in Redmond and will travel very slowly to end users. With the move to Windows 8, and the corresponding shift in application development models, this paradox is certainly in place. On the one hand, the next version of Windows is widely expected sometime in 2012, and its full-scale deployment will likely push into 2014 or even later.  Meanwhile, there’s a technology that runs on today’s Windows 7, will continue to run in the desktop mode of Windows 8 (the next version’s codename), and provides absolutely the best architectural bridge to the Windows 8 Metro-style application development stack.  That technology is Silverlight.  And given what we now know about Windows 8, one might think, as I do, that Microsoft ecosystem developers should be flocking to it. But because developers are trying to get a jump on the future, and since many of them believe the impending v5.0 release of Silverlight will be the technology’s last, not everyone is flocking to it; in fact some are fleeing from it.  Is this sensible?  Is it not unprecedented?  What options does it lead to?  What’s the right way to think about the situation? Is v5.0 really the last major version of the technology called Silverlight?  We don’t know.  But Scott Guthrie, the “father” and champion of the technology, left the Developer Division of Microsoft months ago to work on the Windows Azure team, and he took his people with him.  John Papa, who was a very influential Redmond-based evangelist for Silverlight (and is a Visual Studio Magazine author), left Microsoft completely.  About a year ago, when initial suspicion of Silverlight’s demise reached significant magnitude, Papa interviewed Guthrie on video and their discussion served to dispel developers’ fears; but now they’ve moved on. So read into that what you will and let’s suppose, for the sake of argument, speculation that Silverlight’s days of major revision and iteration are over now is correct.  Let’s assume the shine and glimmer has dimmed.  Let’s assume that any Silverlight application written today, and that therefore any investment of financial and human resources made in Silverlight development today, is destined for rework and extra investment in a few years, if the application’s platform needs to stay current. Is this really so different from any technology investment we make?  Every framework, language, runtime and operating system is subject to change, to improvement, to flux and, yes, to obsolescence.  What differs from project to project, is how near-term that obsolescence is and how disruptive the change will be.  The shift from .NET 1.1. to 2.0 was incremental.  Some of the further changes were too.  But the switch from Windows Forms to WPF was major, and the change from ASP.NET Web Services (asmx) to Windows Communication Foundation (WCF) was downright fundamental. Meanwhile, the transition to the .NET development model for Windows 8 Metro-style applications is actually quite gentle.  The finer points of this subject are covered nicely in Magenic’s excellent white paper “Assessing the Windows 8 Development Platform.” As the authors of that paper (including Rocky Lhotka)  point out, Silverlight code won’t just “port” to Windows 8.  And, no, Silverlight user interfaces won’t either; Metro always supports XAML, but that relationship is not commutative.  But the concepts, the syntax, the architecture and developers’ skills map from Silverlight to Windows 8 Metro and the Windows Runtime (WinRT) very nicely.  That’s not a coincidence.  It’s not an accident.  This is a protected transition.  It’s not a slap in the face. There are few things that are unnerving about this transition, which make it seem markedly different from others: The assumed end of the road for Silverlight is something many think they can see.  Instead of being ignorant of the technology’s expiration date, we believe we know it.  If ignorance is bliss, it would seem our situation lacks it. The new technology involving WinRT and Metro involves a name change from Silverlight. .NET, which underlies both Silverlight and the XAML approach to WinRT development, has just about reached 10 years of age.  That’s equivalent to 80 in human years, or so many fear. My take is that the combination of these three factors has contributed to what for many is a psychologically compelling case that Silverlight should be abandoned today and HTML 5 (the agnostic kind, not the Windows RT variety) should be embraced in its stead.  I understand the logic behind that.  I appreciate the preemptive, proactive, vigilant conscientiousness involved in its calculus.  But for a great many scenarios, I don’t agree with it.  HTML 5 clients, no matter how impressive their interactivity and the emulation of native application interfaces they present may be, are still second-class clients.  They are getting better, especially when hardware acceleration and fast processors are involved.  But they still lag.  They still feel like they’re emulating something, like they’re prototypes, like they’re not comfortable in their own skins.  They are based on compromise, and they feel compromised too. HTML 5/JavaScript development tools are getting better, and will get better still, but they are not as productive as tools for other environments, like Flash, like Silverlight or even more primitive tooling for iOS or Android.  HTML’s roots as a document markup language, rather than an application interface, create a disconnect that impedes productivity.  I do not necessarily think that problem is insurmountable, but it’s here today. If you’re building line-of-business applications, you need a first-class client and you need productivity.  Lack of productivity increases your costs and worsens your backlog.  A second class client will erode user satisfaction, which is never good.  Worse yet, this erosion will be inconspicuous, rather than easily identified and diagnosed, because the inferiority of an HTML 5 client over a native one is hard to identify and, notably, doing so at this juncture in the industry is unpopular.  Why would you fault a technology that everyone believes is revolutionary?  Instead, user disenchantment will remain latent and yet will add to the malaise caused by slower development. If you’re an ISV and you’re coveting the reach of running multi-platform, it’s a different story.  You’ve likely wanted to move to HTML 5 already, and the uncertainty around Silverlight may be the only remaining momentum or pretext you need to make the shift.  You’re deploying many more copies of your application than a line-of-business developer is anyway; this makes the economic hit from lower productivity less impactful, and the wider potential installed base might even make it profitable. But no matter who you are, it’s important to take stock of the situation and do it accurately.  Continued, but merely incremental changes in a development model lead to conservatism and general lack of innovation in the underlying platform.  Periods of stability and equilibrium are necessary, but permanence in that equilibrium leads to loss of platform relevance, market share and utility.  Arguably, that’s already happened to Windows.  The change Windows 8 brings is necessary and overdue.  The marked changes in using .NET if we’re to build applications for the new OS are inevitable.  We will ultimately benefit from the change, and what we can reasonably hope for in the interim is a migration path for our code and skills that is navigable, logical and conceptually comfortable. That path takes us to a place called WinRT, rather than a place called Silverlight.  But considering everything that is changing for the good, the number of disruptive changes is impressively minimal.  The name may be changing, and there may even be some significance to that in terms of Microsoft’s internal management of products and technologies.  But as the consumer, you should care about the ingredients, not the name.  Turkish coffee and Greek coffee are much the same. Although you’ll find plenty of interested parties who will find the names significant, drinkers of the beverage should enjoy either one.  It’s all coffee, it’s all sweet, and you can tell your fortune from the grounds that are left at the end.  Back on the software side, it’s all XAML, and C# or VB .NET, and you can make your fortune from the product that comes out at the end.  Coffee drinkers wouldn’t switch to tea.  Why should XAML developers switch to HTML?

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• Announcement: Employee Info Starter Kit (v5.0) is Released

  - by Mohammad Ashraful Alam

  Ever wanted to have a simple jQuery menu bound with ASP.NET web site map file? Ever wanted to have cool css design stuffs implemented on your ASP.NET data bound controls? Ever wanted to let Visual Studio generate logical layers for you, which can be easily tested, customized and bound with ASP.NET data controls? If your answers with respect to above questions are ‘yes’, then you will probably happy to try out latest release (v5.0) of Employee Starter Kit, which is intended to address different types of real world challenges faced by web application developers when performing common CRUD operations. Using a single database table ‘Employee’, the current release illustrates how to utilize Microsoft ASP.NET 4.0 Web Form Data Controls, Entity Framework 4.0 and Visual Studio 2010 effectively in that context. Employee Info Starter Kit is an open source ASP.NET project template that is highly influenced by the concept ‘Pareto Principle’ or 80-20 rule, where it is targeted to enable a web developer to gain 80% productivity with 20% of effort with respect to learning curve and production. This project template is titled as “Employee Info Starter Kit”, which was initially hosted on Microsoft Code Gallery and been downloaded 1, 50,000+ of copies afterword.  The latest version of this starter kit is hosted in Codeplex. Release Highlights User End Functional Specification The user end functionalities of this starter kit are pretty simple and straight forward that are focused in to perform CRUD operation on employee records as described below. Creating a new employee record Read existing employee records Update an existing employee record Delete existing employee records Architectural Overview Simple 3 layer architecture (presentation, business logic and data access layer) ASP.NET web form based user interface Built-in code generators for logical layers, implemented in Visual Studio default template engine (T4) Built-in Entity Framework entities as business entities (aka: data containers) Data Mapper design pattern based Data Access Layer, implemented in C# and Entity Framework Domain Model design pattern based Business Logic Layer, implemented in C# Object Model for Cross Cutting Concerns (such as validation, logging, exception management) Minimum System Requirements Visual Studio 2010 (Web Developer Express Edition) or higher Sql Server 2005 (Express Edition) or higher Technology Utilized Programming Languages/Scripts Browser side: JavaScript Web server side: C# Code Generation Template: T-4 Template Frameworks .NET Framework 4.0 JavaScript Framework: jQuery 1.5.1 CSS Framework: 960 grid system .NET Framework Components .NET Entity Framework .NET Optional/Named Parameters (new in .net 4.0) .NET Tuple (new in .net 4.0) .NET Extension Method .NET Lambda Expressions .NET Anonymous Type .NET Query Expressions .NET Automatically Implemented Properties .NET LINQ .NET Partial Classes and Methods .NET Generic Type .NET Nullable Type ASP.NET Meta Description and Keyword Support (new in .net 4.0) ASP.NET Routing (new in .net 4.0) ASP.NET Grid View (CSS support for sorting - (new in .net 4.0)) ASP.NET Repeater ASP.NET Form View ASP.NET Login View ASP.NET Site Map Path ASP.NET Skin ASP.NET Theme ASP.NET Master Page ASP.NET Object Data Source ASP.NET Role Based Security Getting Started Guide To see Employee Info Starter Kit in action is pretty easy! Download the latest version. Extract the file. From the extracted folder click the C# project file (Eisk.Web.csproj) to open it in Visual Studio 2010 Hit Ctrl+F5! The current release (v5.0) of Employee Info Starter Kit is properly packaged, fully documented and well tested. If you want to learn more about it in details, just check the following links: Release Home Page Installation Walkthrough Hand on Coding Walkthrough Technical Reference Enjoy!

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• Java in Flux: Utopia or Deuteranopia?

  - by Tori Wieldt

  What a difference a year makes, indeed. Steve Harris, Senior VP, App Server Dev, Oracle and Adam Messinger, VP, Fusion Middleware Group, Oracle presented an informative keynote at the TheServerSide Java Symposium today. With a title "Java in Flux: Utopia or Deuteranopia?" you know things are going to be interesting (see Aeon Flux if you don't get the title reference).What a YearThey started with a little background, explaining that the reactions to Oracle's acquisition of Sun (and therefore Java) one year ago varied greatly, from "Freak Out!" to "Don't Panic." From the Oracle perspective, being the steward of and key contributor to Java requires a lot of sausage making.  They admitted to Oracle's fair share of Homer Simpson-esque "D'oh" moments in the past year, which was complicated by Oracle's communication style.   "Oracle has a tradition has a saying a few things and sticking by then, in contrast to Sun who was much more open," Adam explained. "We laid out the Java roadmap and are executing on it, and we hope that speaks to our commitment."Java SEAdam talked about having a long term perspective on the Java language (20+ years), letting ideas mature in more experimental languages, then bringing them into Java. Current priorities include: JVM convergence (getting the best features of JRockit into Hotspot); support of parallel/multi-core programming, and of course, all the improvements in JDK7. The JDK7 Developer Preview is underway (please download now and report bugs!). The Oracle development team is also working on Lambda and modularity (Jigsaw) for SE 8. Less certain, but also under discussion are improvements for Java SE 9. Adam is thinking of it as a "back to basics" release. He mentioned reworking JNI, improving data integration and improved device support.Java EE To provide context about Java EE, Steve said Java EE was great at getting businesses on the internet. The success of Java EE resulted in an incredible expansion of the middleware marketplace for developers and vendors.  But with success, came more. Java EE kept piling on capabilities, but that created excess baggage.  Doing simple things was no longer so simple. That's where Java community is so valuable: "When Java EE was too complex and heavyweight, many people were happy to tell us what we were doing wrong and popularize solutions," Steve explained. Because of that feedback, the Java EE teams focused on making things simple again: POJOs and annotations, and leveraging changes in Java SE.  Steve said that "innovation doesn't happen in expert groups, it happens on the ground where developers are solving problems," and platform stewards need to pay attention and take advantage of changes that are taking place.Enter the Cloud "Developers are restless, they want cloud functionality from their own IT dept" Steve explained. With the cloud, the scope of problem has expanded to include the data center itself, with multiple tenants. To move forward, existing APIs in Java EE need to be updated to be tenant-aware, service-enabled, and EE needs to support various styles of deployment. The goal is to get all that done in Java EE 8.Adam questioned Steve about timing and schedule. "Yes, the schedule is aggressive, but it'll work" Steve said. Then Adam asked about modularization. If Java SE 8 comes out at the end of 2012, when can Java EE deliver modularization? Steve suggested that key stakeholders can come with up some pre-SE 8 agreement on how to expose the metadata about modules. He then alluded to Mark Reinhold and John Duimovich's keynote at EclipseCON next week. Stay tuned.Evil Master PlanIn conclusion, Adam finally admitted to Oracle's Evil Master Plan: 1) Invest in and improve Java SE and EE 2) Collaborate with the community 3) Broaden the marketplace for Java development. Bwaaaaaaaaahahaha! <rubs hands together>Key LinksJDK7 Developer Preview  http://jdk7.java.net/preview/Oracle Technology Network http://www.oracle.com/technetwork/java/index.htmlTheServerSide Java Symposium  http://javasymposium.techtarget.com/"Utopia or Deuteranopia?" http://en.wikipedia.org/wiki/Aeon_Flux

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• Using the latest (stable release) of Oracle Developer Tools for Visual Studio 11.1.0.7.20.

  - by mbcrump

  +  = Simple and safe Data connections.   This guide is for someone wanting to use the latest ODP.NET quickly without reading the official documentation. This guide will get you up and running in about 15 minutes. I have reviewed my referral link to my simple Setting up ODP.net with Win7 x64 and noticed most people were searching for one of the following terms: “how to use odp.net with vs” “setup connection odp.net” “query db using odp and vs” While my article provided links and a sample tnsnames.ora file, it really didn’t tell you how to use it. I’m hoping that this brief tutorial will help. So before we get started, you will need the following: Download the following: www.oracle.com/technology/software/tech/dotnet/utilsoft.html from oracle and install it. It is the first one on the page. Visual Studio 2008 or 2010. It should be noted that The System.Data.OracleClient namespace is the OLD .NET Framework Data Provider for Oracle. It should not be used anymore as it has been depreciated. The latest version which is what we are using is Oracle.DataAccess.Client. First things first, Add a reference to the Oracle.DataAccess.Client after you install ODP.NET   Copy and paste the following C# code into your project and replace the relevant info including the query string and you should be able to return data. I have commented several lines of code to assist in understanding what it is doing.   Lambda Expression. using System; using System.Data; using Oracle.DataAccess.Client;   namespace ConsoleApplication1 {     class Program     {         static void Main(string[] args)         {           try         {             //Setup DataSource             string oradb = "Data Source=(DESCRIPTION ="                                    + "(ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = hostname)(PORT = 1521)))"                                    + "(CONNECT_DATA = (SERVICE_NAME = SERVICENAME))) ;"                                    + "Persist Security Info=True;User ID=USER;Password=PASSWORD;";                        //Open Connection to Oracle - this could be moved outside the try.             OracleConnection conn = new OracleConnection(oradb);             conn.Open();               //Create cmd and use parameters to prevent SQL injection attacks.             OracleCommand cmd = new OracleCommand();             cmd.Connection = conn;               cmd.CommandText = "select username from table where username = :username";               OracleParameter p1 = new OracleParameter("username", OracleDbType.Varchar2);             p1.Value = username;             cmd.Parameters.Add(p1);               cmd.CommandType = CommandType.Text;               OracleDataReader dr = cmd.ExecuteReader();             dr.Read();               //Contains the value of the datarow             Console.WriteLine(dr["username"].ToString());               //Disposes of objects.             dr.Dispose();             cmd.Dispose();             conn.Dispose();         }           catch (OracleException ex) // Catches only Oracle errors         {             switch (ex.Number)             {                 case 1:                     Console.WriteLine("Error attempting to insert duplicate data.");                     break;                 case 12545:                     Console.WriteLine("The database is unavailable.");                     break;                 default:                     Console.WriteLine(ex.Message.ToString());                     break;             }         }           catch (Exception ex) // Catches any error not previously caught         {                   Console.WriteLine("Unidentified Error: " + ex.Message.ToString());              }         }       }           } At this point, you should have a working Program that returns data from an oracle database. If you are still having trouble then drop me a line and I will be happy to assist. As of this writing, oracle has announced the latest beta release of ODP.NET 11.2.0.1.1 Beta.  This release includes .NET Framework 4 and .NET Framework 4 Client Profile support. You may want to hold off on this version for a while as its BETA, and I wouldn’t want any production code using any BETA software.

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• 45 minutes to talk about C# [closed]

  - by Philip

  I have the opportunity to give a 45 minute talk on C# in the theory of programming languages class I'm taking. The college teaches Java almost exclusively, so that's what all the students are most familiar with. (There's a little C, assembly, Prolog and LISP as well.) I decide what to talk about. It seems to me the best approach is to focus on a few of the big, obvious differences between C# and Java. I don't intend it to be a recommendation to use C# -- there are reasons to use each, mostly because of their ecosystems. So I want to focus on C# as a language. I don't want to go too fast and end up listing a whole bunch of features without showing their usefulness. My current plan is this: Functions as first class objects. This is, in my opinion, one of the biggest differences between C# and Java. The professor briefly mentioned this notion and showed a LISP example, but many of the students have probably never used it. I can show real world examples where it's made my code more readable. Lambda expressions as concise syntax for anonymous functions. Obviously with examples to show how this is useful. The real hit-home examples will be at the end when it's combined with the rest. I don't see an advantage to first showing the old delegate syntax and then replacing it with lambdas -- most of us won't have ever seen delegates anyway so it would just be confusing. The yield keyword and how it's different from returning an array. I have the impression that a lot of C# developers aren't familiar with how to use this. It will likely be very foreign to Java developers. I have some examples from my own work where it was really useful, such as iterating over a tree traversal, or iterating over neighbors in a graph where the neighbors aren't stored in memory. In both cases, doing it in Java would likely mean returning a complete list -- with yield I can stop iterating if I find what I want early on, without using memory for superfluous lists or arrays. Extension methods as a way to write implementation on interfaces. We'll all be familiar with how interfaces don't allow method implementation, and how this leads to code duplication. I'll show a specific example of this and how the extension method can solve the problem. Demonstrate how the above can be combined by implementing some simple Linq methods and using them. Where, Select, First, maybe more depending on how much time is left. Ideas on which ones might 'hit home' the best? There are other things I could talk about such as generics, value types, properties and more. I haven't yet though of good ways to incorporate these. In the case of generics and value types, the advantages might not be obvious or as relevant. Properties are obviously useful, particularly since we're taught strict JavaBeans here, but I don't know if I could integrate it with the "path to Linq" discussion above without it feeling tacked on. So I'm looking for thoughts on how to talk about C#, and what to talk about. Even minor details. I'm sure there are more experienced C# developers than me here who have good insight about what's really important in the language, and what would miss the point.

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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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• Sprinkle Some Magik on that Java Virtual Machine

  - by Jim Connors

  GE Energy, through its Smallworld subsidiary, has been providing geospatial software solutions to the utility and telco markets for over 20 years.  One of the fundamental building blocks of their technology is a dynamically-typed object oriented programming language called Magik.  Like Java, Magik source code is compiled down to bytecodes that run on a virtual machine -- in this case the Magik Virtual Machine. Throughout the years, GE has invested considerable engineering talent in the support and maintenance of this virtual machine.  At the same time vast energy and resources have been invested in the Java Virtual Machine. The question for GE has been whether to continue to make that investment on its own or to leverage massive effort provided by the Java community? Utilizing the Java Virtual Machine instead of maintaining its own virtual machine would give GE more opportunity to focus on application solutions.   At last count, there are dozens, perhaps hundreds of examples of programming languages that have been hosted atop the Java Virtual Machine.  Prior to the release of Java 7, that effort, although certainly possible, was generally less than optimal for languages like Magik because of its dynamic nature.  Java, as a statically typed language had little use for this capability.  In the quest to be a more universal virtual machine, Java 7, via JSR-292, introduced a new bytecode called invokedynamic.  In short, invokedynamic affords a more flexible method call mechanism needed by dynamic languages like Magik. With this new capability GE Energy has succeeded in hosting their Magik environment on top of the Java Virtual Machine.  So you may ask, why would GE wish to do such a thing?  The benefits are many: Competitors to GE Energy claimed that the Magik environment was proprietary.  By utilizing the Java Virtual Machine, that argument gets put to bed.  JVM development is done in open source, where contributions are made world-wide by all types of organizations and individuals. The unprecedented wealth of class libraries and applications written for the Java platform are now opened up to Magik/JVM platform as first class citizens. In addition, the Magik/JVM solution vastly increases the developer pool to include the 9 million Java developers -- the largest developer community on the planet. Applications running on the JVM showed substantial performance gains, in some cases as much as a 5x speed up over the original Magik platform. Legacy Magik applications can still run on the original platform.  They can be seamlessly migrated to run on the JVM by simply recompiling the source code. GE can now leverage the huge Java community.  Undeniably the best virtual machine ever created, hundreds if not thousands of world class developers continually improve, poke, prod and scrutinize all aspects of the Java platform.  As enhancements are made, GE automatically gains access to these. As Magik has little in the way of support for multi-threading, GE will benefit from current and future Java offerings (e.g. lambda expressions) that aim to further facilitate multi-core/multi-threaded application development. As the JVM is available for many more platforms, it broadens the reach of Magik, including the potential to run on a class devices never envisioned just a few short years ago.  For example, Java SE compatible runtime environments are available for popular embedded ARM/Intel/PowerPC configurations that could theoretically host this software too. As compared to other JVM language projects, the Magik integration differs in that it represents a serious commercial entity betting a sizable part of its business on the success of this effort.  Expect to see announcements not only from General Electric, but other organizations as they realize the benefits of utilizing the Java Virtual Machine.

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• Additional new material WebLogic Community

  - by JuergenKress

  Virtual Developer Conference On Demand - Register Updated Book: WebLogic 12c: Distinctive Recipes - Architecture, Development, Administration by Oracle ACE Director Frank Munz - Blog | YouTube Webcast: Migrating from GlassFish to WebLogic - Replay Reliance Commercial Finance Accelerates Time-to-Market, Improves IT Staff Productivity by 70% - Blog | Oracle Magazine Retrieving WebLogic Server Name and Port in ADF Application by Andrejus Baranovskis, Oracle Ace Director - Blog Using Oracle WebLogic 12c with NetBeans IDEOracle ACE Director Markus Eisele walks you through installing and configuring all the necessary components, and helps you get started with a simple Hello World project. Read the article. Video: Oracle A-Team ADF Mobile Persistence SampleThis video by Oracle Fusion Middleware A-Team architect Steven Davelaar demonstrates how to use the ADF Mobile Persistence Sample JDeveloper extension to generate a fully functional ADF Mobile application that reads and writes data using an ADF BC SOAP web service. Watch the video. Java ME 8 ReleaseDownload Java ME today! This release is an implementation of the Java ME 8 standards JSR 360 (CLDC 8) and JSR 361 (MEEP 8), and includes support of alignment with Java SE 8 language features and APIs, an enhanced services-enabled application platform, the ability to "right-size" the platform to address a wide range of target devices, and more. Learn more Download Java ME SDK 8It includes application development support for Oracle Java ME Embedded 8 platforms and includes plugins for NetBeans 8. See the Java ME 8 Developer Tools Documentation to learn JavaOne 2014 Early Bird RateRegister early to save $400 off the onsite price. With the release of Java 8 this year, we have exciting new sessions and an interactive demo space! NetBeans IDE 8.0 Patch UpdateThe NetBeans Team has released a patch for NetBeans IDE 8.0. Download it today to get fixes that enhance stability and performance. Java 8 Questions ForumFor any questions about this new release, please join the conversation on the Java 8 Questions Forum. Java ME 8: Getting Started with Samples and Demo CodeLearn in few steps how to get started with Java ME 8! The New Java SE 8 FeaturesJava SE 8 introduces enhancements such as lambda expressions that enable you to write more concise yet readable code, better utilize multicore systems, and detect more errors at compile time. See What's New in JDK 8 and the new Java SE 8 documentation portal. Pay Less for Java-Related Books!Save 20% on all new Oracle Press books related to Java. Download the free preview sampler for the Java 8 book written by Herbert Schildt, Maurice Naftain, Henrik Ebbers and J.F. DiMarzio. New book: EJB 3 in Action, Second Edition WebLogic 12c Does WebSockets Getting Started by C2B2 Video: Building Robots with Java Embedded Video: Nighthacking TV Watch presentations by Stephen Chin and community members about Java SE, Java Embedded, Java EE, Hadoop, Robots and more. Migrating the Spring Pet Clinic to Java EE 7 Trip report : Jozi JUG Java Day in Johannesburg How to Build GlassFish 4 from Source 4,000 posts later : The Aquarium WebLogic Partner Community For regular information become a member in the WebLogic Partner Community please visit: http://www.oracle.com/partners/goto/wls-emea ( OPN account required). If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Mix Forum Wiki Technorati Tags: WebLogic,WebLogic Community,Oracle,OPN,Jürgen Kress

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