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• Windows Azure: Announcing release of Windows Azure SDK 2.2 (with lots of goodies)

  - by ScottGu

  Earlier today I blogged about a big update we made today to Windows Azure, and some of the great new features it provides. Today I’m also excited to also announce the release of the Windows Azure SDK 2.2. Today’s SDK release adds even more great features including: Visual Studio 2013 Support Integrated Windows Azure Sign-In support within Visual Studio Remote Debugging Cloud Services with Visual Studio Firewall Management support within Visual Studio for SQL Databases Visual Studio 2013 RTM VM Images for MSDN Subscribers Windows Azure Management Libraries for .NET Updated Windows Azure PowerShell Cmdlets and ScriptCenter The below post has more details on what’s available in today’s Windows Azure SDK 2.2 release.  Also head over to Channel 9 to see the new episode of the Visual Studio Toolbox show that will be available shortly, and which highlights these features in a video demonstration. Visual Studio 2013 Support Version 2.2 of the Window Azure SDK is the first official version of the SDK to support the final RTM release of Visual Studio 2013. If you installed the 2.1 SDK with the Preview of Visual Studio 2013 we recommend that you upgrade your projects to SDK 2.2.  SDK 2.2 also works side by side with the SDK 2.0 and SDK 2.1 releases on Visual Studio 2012: Integrated Windows Azure Sign In within Visual Studio Integrated Windows Azure Sign-In support within Visual Studio is one of the big improvements added with this Windows Azure SDK release.  Integrated sign-in support enables developers to develop/test/manage Windows Azure resources within Visual Studio without having to download or use management certificates.  You can now just right-click on the “Windows Azure” icon within the Server Explorer inside Visual Studio and choose the “Connect to Windows Azure” context menu option to connect to Windows Azure: Doing this will prompt you to enter the email address of the account you wish to sign-in with: You can use either a Microsoft Account (e.g. Windows Live ID) or an Organizational account (e.g. Active Directory) as the email.  The dialog will update with an appropriate login prompt depending on which type of email address you enter: Once you sign-in you’ll see the Windows Azure resources that you have permissions to manage show up automatically within the Visual Studio Server Explorer (and you can start using them): With this new integrated sign in experience you are now able to publish web apps, deploy VMs and cloud services, use Windows Azure diagnostics, and fully interact with your Windows Azure services within Visual Studio without the need for a management certificate.  All of the authentication is handled using the Windows Azure Active Directory associated with your Windows Azure account (details on this can be found in my earlier blog post). Integrating authentication this way end-to-end across the Service Management APIs + Dev Tools + Management Portal + PowerShell automation scripts enables a much more secure and flexible security model within Windows Azure, and makes it much more convenient to securely manage multiple developers + administrators working on a project.  It also allows organizations and enterprises to use the same authentication model that they use for their developers on-premises in the cloud.  It also ensures that employees who leave an organization immediately lose access to their company’s cloud based resources once their Active Directory account is suspended. Filtering/Subscription Management Once you login within Visual Studio, you can filter which Windows Azure subscriptions/regions are visible within the Server Explorer by right-clicking the “Filter Services” context menu within the Server Explorer.  You can also use the “Manage Subscriptions” context menu to mange your Windows Azure Subscriptions: Bringing up the “Manage Subscriptions” dialog allows you to see which accounts you are currently using, as well as which subscriptions are within them: The “Certificates” tab allows you to continue to import and use management certificates to manage Windows Azure resources as well.  We have not removed any functionality with today’s update – all of the existing scenarios that previously supported management certificates within Visual Studio continue to work just fine.  The new integrated sign-in support provided with today’s release is purely additive. Note: the SQL Database node and the Mobile Service node in Server Explorer do not support integrated sign-in at this time. Therefore, you will only see databases and mobile services under those nodes if you have a management certificate to authorize access to them.  We will enable them with integrated sign-in in a future update. Remote Debugging Cloud Resources within Visual Studio Today’s Windows Azure SDK 2.2 release adds support for remote debugging many types of Windows Azure resources. With live, remote debugging support from within Visual Studio, you are now able to have more visibility than ever before into how your code is operating live in Windows Azure.  Let’s walkthrough how to enable remote debugging for a Cloud Service: Remote Debugging of Cloud Services To enable remote debugging for your cloud service, select Debug as the Build Configuration on the Common Settings tab of your Cloud Service’s publish dialog wizard: Then click the Advanced Settings tab and check the Enable Remote Debugging for all roles checkbox: Once your cloud service is published and running live in the cloud, simply set a breakpoint in your local source code: Then use Visual Studio’s Server Explorer to select the Cloud Service instance deployed in the cloud, and then use the Attach Debugger context menu on the role or to a specific VM instance of it: Once the debugger attaches to the Cloud Service, and a breakpoint is hit, you’ll be able to use the rich debugging capabilities of Visual Studio to debug the cloud instance remotely, in real-time, and see exactly how your app is running in the cloud. Today’s remote debugging support is super powerful, and makes it much easier to develop and test applications for the cloud.  Support for remote debugging Cloud Services is available as of today, and we’ll also enable support for remote debugging Web Sites shortly. Firewall Management Support with SQL Databases By default we enable a security firewall around SQL Databases hosted within Windows Azure.  This ensures that only your application (or IP addresses you approve) can connect to them and helps make your infrastructure secure by default.  This is great for protection at runtime, but can sometimes be a pain at development time (since by default you can’t connect/manage the database remotely within Visual Studio if the security firewall blocks your instance of VS from connecting to it). One of the cool features we’ve added with today’s release is support that makes it easy to enable and configure the security firewall directly within Visual Studio.  Now with the SDK 2.2 release, when you try and connect to a SQL Database using the Visual Studio Server Explorer, and a firewall rule prevents access to the database from your machine, you will be prompted to add a firewall rule to enable access from your local IP address: You can simply click Add Firewall Rule and a new rule will be automatically added for you. In some cases, the logic to detect your local IP may not be sufficient (for example: you are behind a corporate firewall that uses a range of IP addresses) and you may need to set up a firewall rule for a range of IP addresses in order to gain access. The new Add Firewall Rule dialog also makes this easy to do.  Once connected you’ll be able to manage your SQL Database directly within the Visual Studio Server Explorer: This makes it much easier to work with databases in the cloud. Visual Studio 2013 RTM Virtual Machine Images Available for MSDN Subscribers Last week we released the General Availability Release of Visual Studio 2013 to the web.  This is an awesome release with a ton of new features. With today’s Windows Azure update we now have a set of pre-configured VM images of VS 2013 available within the Windows Azure Management Portal for use by MSDN customers.  This enables you to create a VM in the cloud with VS 2013 pre-installed on it in with only a few clicks: Windows Azure now provides the fastest and easiest way to get started doing development with Visual Studio 2013. Windows Azure Management Libraries for .NET (Preview) Having the ability to automate the creation, deployment, and tear down of resources is a key requirement for applications running in the cloud.  It also helps immensely when running dev/test scenarios and coded UI tests against pre-production environments. Today we are releasing a preview of a new set of Windows Azure Management Libraries for .NET.  These new libraries make it easy to automate tasks using any .NET language (e.g. C#, VB, F#, etc).  Previously this automation capability was only available through the Windows Azure PowerShell Cmdlets or to developers who were willing to write their own wrappers for the Windows Azure Service Management REST API. Modern .NET Developer Experience We’ve worked to design easy-to-understand .NET APIs that still map well to the underlying REST endpoints, making sure to use and expose the modern .NET functionality that developers expect today: Portable Class Library (PCL) support targeting applications built for any .NET Platform (no platform restriction) Shipped as a set of focused NuGet packages with minimal dependencies to simplify versioning Support async/await task based asynchrony (with easy sync overloads) Shared infrastructure for common error handling, tracing, configuration, HTTP pipeline manipulation, etc. Factored for easy testability and mocking Built on top of popular libraries like HttpClient and Json.NET Below is a list of a few of the management client classes that are shipping with today’s initial preview release: .NET Class Name Supports Operations for these Assets (and potentially more) ManagementClient Locations Credentials Subscriptions Certificates ComputeManagementClient Hosted Services Deployments Virtual Machines Virtual Machine Images & Disks StorageManagementClient Storage Accounts WebSiteManagementClient Web Sites Web Site Publish Profiles Usage Metrics Repositories VirtualNetworkManagementClient Networks Gateways Automating Creating a Virtual Machine using .NET Let’s walkthrough an example of how we can use the new Windows Azure Management Libraries for .NET to fully automate creating a Virtual Machine. I’m deliberately showing a scenario with a lot of custom options configured – including VHD image gallery enumeration, attaching data drives, network endpoints + firewall rules setup - to show off the full power and richness of what the new library provides. We’ll begin with some code that demonstrates how to enumerate through the built-in Windows images within the standard Windows Azure VM Gallery.  We’ll search for the first VM image that has the word “Windows” in it and use that as our base image to build the VM from.  We’ll then create a cloud service container in the West US region to host it within: We can then customize some options on it such as setting up a computer name, admin username/password, and hostname.  We’ll also open up a remote desktop (RDP) endpoint through its security firewall: We’ll then specify the VHD host and data drives that we want to mount on the Virtual Machine, and specify the size of the VM we want to run it in: Once everything has been set up the call to create the virtual machine is executed asynchronously In a few minutes we’ll then have a completely deployed VM running on Windows Azure with all of the settings (hard drives, VM size, machine name, username/password, network endpoints + firewall settings) fully configured and ready for us to use: Preview Availability via NuGet The Windows Azure Management Libraries for .NET are now available via NuGet. Because they are still in preview form, you’ll need to add the –IncludePrerelease switch when you go to retrieve the packages. The Package Manager Console screen shot below demonstrates how to get the entire set of libraries to manage your Windows Azure assets: You can also install them within your .NET projects by right clicking on the VS Solution Explorer and using the Manage NuGet Packages context menu command.  Make sure to select the “Include Prerelease” drop-down for them to show up, and then you can install the specific management libraries you need for your particular scenarios: Open Source License The new Windows Azure Management Libraries for .NET make it super easy to automate management operations within Windows Azure – whether they are for Virtual Machines, Cloud Services, Storage Accounts, Web Sites, and more.  Like the rest of the Windows Azure SDK, we are releasing the source code under an open source (Apache 2) license and it is hosted at https://github.com/WindowsAzure/azure-sdk-for-net/tree/master/libraries if you wish to contribute. PowerShell Enhancements and our New Script Center Today, we are also shipping Windows Azure PowerShell 0.7.0 (which is a separate download). You can find the full change log here. Here are some of the improvements provided with it: Windows Azure Active Directory authentication support Script Center providing many sample scripts to automate common tasks on Windows Azure New cmdlets for Media Services and SQL Database Script Center Windows Azure enables you to script and automate a lot of tasks using PowerShell.  People often ask for more pre-built samples of common scenarios so that they can use them to learn and tweak/customize. With this in mind, we are excited to introduce a new Script Center that we are launching for Windows Azure. You can learn about how to scripting with Windows Azure with a get started article. You can then find many sample scripts across different solutions, including infrastructure, data management, web, and more: All of the sample scripts are hosted on TechNet with links from the Windows Azure Script Center. Each script is complete with good code comments, detailed descriptions, and examples of usage. Summary Visual Studio 2013 and the Windows Azure SDK 2.2 make it easier than ever to get started developing rich cloud applications. Along with the Windows Azure Developer Center’s growing set of .NET developer resources to guide your development efforts, today’s Windows Azure SDK 2.2 release should make your development experience more enjoyable and efficient. If you don’t already have a Windows Azure account, you can sign-up for a free trial and start using all of the above features today.  Then visit the Windows Azure Developer Center to learn more about how to build apps with it. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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• #MIX Day 2 Keynote: Put the Phone Down and Listen

  - by andrewbrust

  MIX day 1’s keynote was all about Windows Phone 7 (WP7).  MIX day 2’s was a reminder that Microsoft has much more going on than a new mobile platform.  Steven Sinofsky, Scott Guthrie, Doug Purdy and others showed us lots of other good things coming from Microsoft, mostly in the developer stack, that we certainly shouldn’t overlook.  These included the forthcoming IE9, its new JavaScript compiling engine and support for HTML 5 that takes full advantage of the local PC resources, including the Graphics Processing Unit.  The announcements also included important additions to ASP.NET (and one subtraction, in the form of lighter-weight ViewState technology) including almost-obsessive jQuery support.  That support is so good that John Resig, creator of the jQuery project, came on stage to tell us so.  Then Scott Guthrie told us that Microsoft would be contributing code to Open Source jQuery project. This is not your father’s Microsoft, it would seem. But to me, the crown jewel in today’s keynote were the numerous announcements around the Open Data Protocol (OData).  OData is nothing more than the protocol side of “Astoria” (now known as WCF Data Services, and until recently called ADO.NET Data Services) separated out and opened up as a platform-neutral standard.  The 2009 Professional Developers Conference (PDC) was Microsoft’s vehicle for first announcing OData, as well as project “Dallas,” an Azure-based cloud platform for publishing commercial OData feeds.  And we had already known about “bridges” for Astoria (and thus OData) for PHP and Java.  We also knew that PowerPivot, Microsoft’s forthcoming self-service BI plug-in for Excel 2010, will consume OData feeds and then facilitate drill-down analysis of their data.  And we recently found out that SQL Reporting Services reports (in the forthcoming SQL Server 2008 R2) and SharePoint 2010 lists will be consumable in OData format as well. So what was left to announce?  How about OData clients for Palm webOS and Apple iPhone/Objective C?  How about the release to Open Source of .NET’s OData client?  Or the ability to publish any SQL Azure database as an OData service by simply checking a checkbox at deployment?  Maybe even a Silverlight tool (code-named “Houston”) to create SQL Azure databases (and then publish them as OData) right in the browser?  And what if you you could get at NetFlix’s entire catalog in OData format?  You can – just go to http://odata.netflix.com/Catalog/ and see for yourself.  Douglas Purdy, who made these announcements said “we want OData to work on as many devices and platforms as possible.”  After all the cross-platform OData announcements made in about a half year’s time, it’s hard to dispute this. When Microsoft plays the data card, and plays it well, watch out, because data programmability is the company’s heritage.  I’ll be discussing OData at length in my April Redmond Review column.  I wrote that column two weeks ago, and was convinced then that OData was a big deal. Today upped the ante even more.  And following the Windows Phone 7 euphoria of yesterday was, I think, smart timing.  The phone, if it’s successful, will be because it’s a good developer platform play.  And developer platforms (as well as their creators) are most successful when they have a good data strategy.  OData is very Silverlight-friendly, and that means it’s WP7-friendly too.  Phone plus service-oriented data is a one-two punch.  A phone platform without data would have been a phone with no signal.

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• Gamify your Web

  - by Isabel F. Peñuelas

  Yesterday Valencia welcomed the Gamification World Congress that I follow virtually through #GWC2012. BBVA, Iberia, Ligeresa, Axe, Wayra, ESADE, GlaxoSmithKline, Macmillan, Gamisfaction, Nomaders, Blaffin were among the companies presenting success stories on gaming. It has been proved that people remember things easily when an emotion is created. The marketing expectations around Gamification techniques have a lot to do with Neuromarketing theories. There are a lot of expectations on internal enterprise Gamification. In the public Web some sectors are taking the lead on following the trend. The Gartner Analyst Brian Burke opened another Gamification recent event in Madrid remembering that “Gamification is mostly about Engagement”, and this can be applied both to customers or employees. Gamification and Banking The experience of the Spanish Financial Group BBVA that just launched BBVA Game was also presented a week ago at the BBVA Innovation Centre during the event “Gamification & Banking: a fad or a serious business?” . One of the objectives of the BBVA Game was to double the name of registered users. “People like the efficiency of the online channel want to keep a one-to-one contact with the brand”-explained Bernardo Crespo. Another interested data coming out the BBVA presentation was that “only 20% of Spanish users –out of the total holders of Bank Accounts in the country- is familiar with the use of a Web Site to consult their bank accounts”, the project aims also to reverse this situation helping people to learn making a heavy use of the Video in the gaming context. In general Banking presenters seem to agree that Gamification techniques are helping to increase the time spent on the Web. Gamification and Health Using Gamification techniques for chronic illness rehabilitation was another topic of the World Congress. Here you can find some ideas and experiences What can games do for the health (In Spanish) I have personally started my own mental-health gaming project at http://www.lumosity.com/ Gamification in the Enterprise I really recommend Reading this excellent post of Ultan ÓBroin my Introduction to Gamification and Applications. Employee´s motivation and learning are experiencing a 360º turn and it looks than some of us will become soon the Dragon of the year instead of the Employee of the Year. Using Web 2.0 Tools for Gamification Projects  What type of tools do we need for a quick-win Gamification project? To certain extend Gamification can be considered an evolution of the participative Web. Badging, avatars, points and awards, leader boards, progress charts, virtual currencies, gifting and giving challenges and quests are common components and elements. The Web is offering new development frameworks to that purpose as this Avatar Framework from Paypal or Badgeville to include in web applications. Besides, tools to create communities around a game are required to comment, share and vote players as well as for an efficient multimedia management. Due to its entirely open architecture, its community features, and its multimedia and imaging solutions is were I see WebCenter as a tool helping brands to success. Link to Sources & Recommended Readings YouTube Video of BBVAGame presentation Where To Apply Gamification In Your Incentive Jim Calhoun Cancer Challenge Ride and Walkh For my Spanish Readers El aburrimiento es el enemigo número uno del éxito

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• Autoscaling in a modern world&hellip;. Part 4

  - by Steve Loethen

  Now that I have the rules and services XML files in the cloud, it is time to sever the bounds of earth and live totally in the cloud.  I have to host the Autoscaling object in Azure as well, point it to the rules, tell it the management certs and get out of the way. A couple of questions.  Where to host?  The most obvious place to me was a worker role.  A simple, single purpose worker role, doing nothing but watching my app.  Here are the steps I used. 1) Created a project.  Separate project from my web site.  I wanted to be able to run the web in the cloud and the autoscaler local for debugging purposes.  Seemed like the easiest way.  2) Add the Wasabi block to the project. 3) Configure the settings.  I used the same settings used for the console app.  It points to the same web role, uses the same rules file.  4) Make sure the certification needed to manage the role is added to the cert store in the sky (“LocalMachine” and “My” are default locations). I ran the worker role in the local fabric.  It worked.  I then published to the cloud, and verified it worked again.  Here is what my code looked like. public override bool OnStart() { Trace.WriteLine("Set Default Connection Limit", "Information"); // Set the maximum number of concurrent connections ServicePointManager.DefaultConnectionLimit = 12; Trace.WriteLine("Set up configuration change code", "Information"); // set up config CloudStorageAccount.SetConfigurationSettingPublisher((configName, configSetter) => configSetter(RoleEnvironment.GetConfigurationSettingValue(configName))); Trace.WriteLine("Get current diagnostic configuration", "Information"); // Get current diagnostic configuration DiagnosticMonitorConfiguration dmc = DiagnosticMonitor.GetDefaultInitialConfiguration(); Trace.WriteLine("Set Diagnostic Buffer Size", "Information"); // Set Diagnostic Buffer size dmc.Logs.BufferQuotaInMB = 4; Trace.WriteLine("Set log transfer period", "Information"); // Set log transfer period dmc.Logs.ScheduledTransferPeriod = TimeSpan.FromMinutes(1); Trace.WriteLine("Set log verbosity", "Information"); // Set log filter to verbose dmc.Logs.ScheduledTransferLogLevelFilter = LogLevel.Verbose; Trace.WriteLine("Start the diagnostic monitor", "Information"); // Start the diagnostic monitor DiagnosticMonitor.Start("Microsoft.WindowsAzure.Plugins.Diagnostics.ConnectionString", dmc); Trace.WriteLine("Get the current Autoscaler from the EntLib Container", "Information"); // Get the current Autoscaler from the EntLib Container scaler = EnterpriseLibraryContainer.Current.GetInstance<Autoscaler>(); Trace.WriteLine("Start the autoscaler", "Information"); // Start the autoscaler scaler.Start(); Trace.WriteLine("call the base class OnStart", "Information"); // call the base class OnStart return base.OnStart(); } public override void OnStop() { Trace.WriteLine("Stop the Autoscaler", "Information"); // Stop the Autoscaler scaler.Stop(); } I did have to turn on some basic logging for wasabi, which will cover in the next post.  This let me figure out that I hadn’t done the certificate step.

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• Building applications with WCF - Intro

  - by skjagini

  I am going to write series of articles using Windows Communication Framework (WCF) to develop client and server applications and this is the first part of that series. What is WCF As Juwal puts in his Programming WCF book, WCF provides an SDK for developing and deploying services on Windows, provides runtime environment to expose CLR types as services and consume services as CLR types. Building services with WCF is incredibly easy and it’s implementation provides a set of industry standards and off the shelf plumbing including service hosting, instance management, reliability, transaction management, security etc such that it greatly increases productivity Scenario: Lets consider a typical bank customer trying to create an account, deposit amount and transfer funds between accounts, i.e. checking and savings. To make it interesting, we are going to divide the functionality into multiple services and each of them working with database directly. We will run test cases with and without transactional support across services. In this post we will build contracts, services, data access layer, unit tests to verify end to end communication etc, nothing big stuff here and we dig into other features of the WCF in subsequent posts with incremental changes. In any distributed architecture we have two pieces i.e. services and clients. Services as the name implies provide functionality to execute various pieces of business logic on the server, and clients providing interaction to the end user. Services can be built with Web Services or with WCF. Service built on WCF have the advantage of binding independent, i.e. can run against TCP and HTTP protocol without any significant changes to the code. Solution Services Profile: For creating a new bank customer, getting details about existing customer ProfileContract ProfileService Checking Account: To get checking account balance, deposit or withdraw amount CheckingAccountContract CheckingAccountService Savings Account: To get savings account balance, deposit or withdraw amount SavingsAccountContract SavingsAccountService ServiceHost: To host services, i.e. running the services at particular address, binding and contract where client can connect to Client: Helps end user to use services like creating account and amount transfer between the accounts BankDAL: Data access layer to work with database     BankDAL It’s no brainer not to use an ORM as many matured products are available currently in market including Linq2Sql, Entity Framework (EF), LLblGenPro etc. For this exercise I am going to use Entity Framework 4.0, CTP 5 with code first approach. There are two approaches when working with data, data driven and code driven. In data driven we start by designing tables and their constrains in database and generate entities in code while in code driven (code first) approach entities are defined in code and the metadata generated from the entities is used by the EF to create tables and table constrains. In previous versions the entity classes had  to derive from EF specific base classes. In EF 4 it  is not required to derive from any EF classes, the entities are not only persistence ignorant but also enable full test driven development using mock frameworks.  Application consists of 3 entities, Customer entity which contains Customer details; CheckingAccount and SavingsAccount to hold the respective account balance. We could have introduced an Account base class for CheckingAccount and SavingsAccount which is certainly possible with EF mappings but to keep it simple we are just going to follow 1 –1 mapping between entity and table mappings. Lets start out by defining a class called Customer which will be mapped to Customer table, observe that the class is simply a plain old clr object (POCO) and has no reference to EF at all. using System;   namespace BankDAL.Model { public class Customer { public int Id { get; set; } public string FullName { get; set; } public string Address { get; set; } public DateTime DateOfBirth { get; set; } } }   In order to inform EF about the Customer entity we have to define a database context with properties of type DbSet<> for every POCO which needs to be mapped to a table in database. EF uses convention over configuration to generate the metadata resulting in much less configuration. using System.Data.Entity;   namespace BankDAL.Model { public class BankDbContext: DbContext { public DbSet<Customer> Customers { get; set; } } }   Entity constrains can be defined through attributes on Customer class or using fluent syntax (no need to muscle with xml files), CustomerConfiguration class. By defining constrains in a separate class we can maintain clean POCOs without corrupting entity classes with database specific information.   using System; using System.Data.Entity.ModelConfiguration;   namespace BankDAL.Model { public class CustomerConfiguration: EntityTypeConfiguration<Customer> { public CustomerConfiguration() { Initialize(); }   private void Initialize() { //Setting the Primary Key this.HasKey(e => e.Id);   //Setting required fields this.HasRequired(e => e.FullName); this.HasRequired(e => e.Address); //Todo: Can't create required constraint as DateOfBirth is not reference type, research it //this.HasRequired(e => e.DateOfBirth); } } }   Any queries executed against Customers property in BankDbContext are executed against Cusomers table. By convention EF looks for connection string with key of BankDbContext when working with the context.   We are going to define a helper class to work with Customer entity with methods for querying, adding new entity etc and these are known as repository classes, i.e., CustomerRepository   using System; using System.Data.Entity; using System.Linq; using BankDAL.Model;   namespace BankDAL.Repositories { public class CustomerRepository { private readonly IDbSet<Customer> _customers;   public CustomerRepository(BankDbContext bankDbContext) { if (bankDbContext == null) throw new ArgumentNullException(); _customers = bankDbContext.Customers; }   public IQueryable<Customer> Query() { return _customers; }   public void Add(Customer customer) { _customers.Add(customer); } } }   From the above code it is observable that the Query methods returns customers as IQueryable i.e. customers are retrieved only when actually used i.e. iterated. Returning as IQueryable also allows to execute filtering and joining statements from business logic using lamba expressions without cluttering the data access layer with tens of methods.   Our CheckingAccountRepository and SavingsAccountRepository look very similar to each other using System; using System.Data.Entity; using System.Linq; using BankDAL.Model;   namespace BankDAL.Repositories { public class CheckingAccountRepository { private readonly IDbSet<CheckingAccount> _checkingAccounts;   public CheckingAccountRepository(BankDbContext bankDbContext) { if (bankDbContext == null) throw new ArgumentNullException(); _checkingAccounts = bankDbContext.CheckingAccounts; }   public IQueryable<CheckingAccount> Query() { return _checkingAccounts; }   public void Add(CheckingAccount account) { _checkingAccounts.Add(account); }   public IQueryable<CheckingAccount> GetAccount(int customerId) { return (from act in _checkingAccounts where act.CustomerId == customerId select act); }   } } The repository classes look very similar to each other for Query and Add methods, with the help of C# generics and implementing repository pattern (Martin Fowler) we can reduce the repeated code. Jarod from ElegantCode has posted an article on how to use repository pattern with EF which we will implement in the subsequent articles along with WCF Unity life time managers by Drew Contracts It is very easy to follow contract first approach with WCF, define the interface and append ServiceContract, OperationContract attributes. IProfile contract exposes functionality for creating customer and getting customer details.   using System; using System.ServiceModel; using BankDAL.Model;   namespace ProfileContract { [ServiceContract] public interface IProfile { [OperationContract] Customer CreateCustomer(string customerName, string address, DateTime dateOfBirth);   [OperationContract] Customer GetCustomer(int id);   } }   ICheckingAccount contract exposes functionality for working with checking account, i.e., getting balance, deposit and withdraw of amount. ISavingsAccount contract looks the same as checking account.   using System.ServiceModel;   namespace CheckingAccountContract { [ServiceContract] public interface ICheckingAccount { [OperationContract] decimal? GetCheckingAccountBalance(int customerId);   [OperationContract] void DepositAmount(int customerId,decimal amount);   [OperationContract] void WithdrawAmount(int customerId, decimal amount);   } }   Services   Having covered the data access layer and contracts so far and here comes the core of the business logic, i.e. services.   .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } ProfileService implements the IProfile contract for creating customer and getting customer detail using CustomerRepository. using System; using System.Linq; using System.ServiceModel; using BankDAL; using BankDAL.Model; using BankDAL.Repositories; using ProfileContract;   namespace ProfileService { [ServiceBehavior(IncludeExceptionDetailInFaults = true)] public class Profile: IProfile { public Customer CreateAccount( string customerName, string address, DateTime dateOfBirth) { Customer cust = new Customer { FullName = customerName, Address = address, DateOfBirth = dateOfBirth };   using (var bankDbContext = new BankDbContext()) { new CustomerRepository(bankDbContext).Add(cust); bankDbContext.SaveChanges(); } return cust; }   public Customer CreateCustomer(string customerName, string address, DateTime dateOfBirth) { return CreateAccount(customerName, address, dateOfBirth); } public Customer GetCustomer(int id) { return new CustomerRepository(new BankDbContext()).Query() .Where(i => i.Id == id).FirstOrDefault(); }   } } From the above code you shall observe that we are calling bankDBContext’s SaveChanges method and there is no save method specific to customer entity because EF manages all the changes centralized at the context level and all the pending changes so far are submitted in a batch and it is represented as Unit of Work. Similarly Checking service implements ICheckingAccount contract using CheckingAccountRepository, notice that we are throwing overdraft exception if the balance falls by zero. WCF has it’s own way of raising exceptions using fault contracts which will be explained in the subsequent articles. SavingsAccountService is similar to CheckingAccountService. using System; using System.Linq; using System.ServiceModel; using BankDAL.Model; using BankDAL.Repositories; using CheckingAccountContract;   namespace CheckingAccountService { [ServiceBehavior(IncludeExceptionDetailInFaults = true)] public class Checking:ICheckingAccount { public decimal? GetCheckingAccountBalance(int customerId) { using (var bankDbContext = new BankDbContext()) { CheckingAccount account = (new CheckingAccountRepository(bankDbContext) .GetAccount(customerId)).FirstOrDefault();   if (account != null) return account.Balance;   return null; } }   public void DepositAmount(int customerId, decimal amount) { using(var bankDbContext = new BankDbContext()) { var checkingAccountRepository = new CheckingAccountRepository(bankDbContext); CheckingAccount account = (checkingAccountRepository.GetAccount(customerId)) .FirstOrDefault();   if (account == null) { account = new CheckingAccount() { CustomerId = customerId }; checkingAccountRepository.Add(account); }   account.Balance = account.Balance + amount; if (account.Balance < 0) throw new ApplicationException("Overdraft not accepted");   bankDbContext.SaveChanges(); } } public void WithdrawAmount(int customerId, decimal amount) { DepositAmount(customerId, -1*amount); } } }   BankServiceHost The host acts as a glue binding contracts with it’s services, exposing the endpoints. The services can be exposed either through the code or configuration file, configuration file is preferred as it allows run time changes to service behavior even after deployment. We have 3 services and for each of the service you need to define name (the class that implements the service with fully qualified namespace) and endpoint known as ABC, i.e. address, binding and contract. We are using netTcpBinding and have defined the base address with for each of the contracts .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } <system.serviceModel> <services> <service name="ProfileService.Profile"> <endpoint binding="netTcpBinding" contract="ProfileContract.IProfile"/> <host> <baseAddresses> <add baseAddress="net.tcp://localhost:1000/Profile"/> </baseAddresses> </host> </service> <service name="CheckingAccountService.Checking"> <endpoint binding="netTcpBinding" contract="CheckingAccountContract.ICheckingAccount"/> <host> <baseAddresses> <add baseAddress="net.tcp://localhost:1000/Checking"/> </baseAddresses> </host> </service> <service name="SavingsAccountService.Savings"> <endpoint binding="netTcpBinding" contract="SavingsAccountContract.ISavingsAccount"/> <host> <baseAddresses> <add baseAddress="net.tcp://localhost:1000/Savings"/> </baseAddresses> </host> </service> </services> </system.serviceModel> Have to open the services by creating service host which will handle the incoming requests from clients.   using System;   namespace ServiceHost { class Program { static void Main(string[] args) { CreateHosts(); Console.ReadLine(); }   private static void CreateHosts() { CreateHost(typeof(ProfileService.Profile),"Profile Service"); CreateHost(typeof(SavingsAccountService.Savings), "Savings Account Service"); CreateHost(typeof(CheckingAccountService.Checking), "Checking Account Service"); }   private static void CreateHost(Type type, string hostDescription) { System.ServiceModel.ServiceHost host = new System.ServiceModel.ServiceHost(type); host.Open();   if (host.ChannelDispatchers != null && host.ChannelDispatchers.Count != 0 && host.ChannelDispatchers[0].Listener != null) Console.WriteLine("Started: " + host.ChannelDispatchers[0].Listener.Uri); else Console.WriteLine("Failed to start:" + hostDescription); } } } BankClient    The client has no knowledge about service business logic other than the functionality it exposes through the contract, end points and a proxy to work against. The endpoint data and server proxy can be generated by right clicking on the project reference and choosing ‘Add Service Reference’ and entering the service end point address. Or if you have access to source, you can manually reference contract dlls and update clients configuration file to point to the service end point if the server and client happens to be being built using .Net framework. One of the pros with the manual approach is you don’t have to work against messy code generated files.   <system.serviceModel> <client> <endpoint name="tcpProfile" address="net.tcp://localhost:1000/Profile" binding="netTcpBinding" contract="ProfileContract.IProfile"/> <endpoint name="tcpCheckingAccount" address="net.tcp://localhost:1000/Checking" binding="netTcpBinding" contract="CheckingAccountContract.ICheckingAccount"/> <endpoint name="tcpSavingsAccount" address="net.tcp://localhost:1000/Savings" binding="netTcpBinding" contract="SavingsAccountContract.ISavingsAccount"/>   </client> </system.serviceModel> The client uses a façade to connect to the services   using System.ServiceModel; using CheckingAccountContract; using ProfileContract; using SavingsAccountContract;   namespace Client { public class ProxyFacade { public static IProfile ProfileProxy() { return (new ChannelFactory<IProfile>("tcpProfile")).CreateChannel(); }   public static ICheckingAccount CheckingAccountProxy() { return (new ChannelFactory<ICheckingAccount>("tcpCheckingAccount")) .CreateChannel(); }   public static ISavingsAccount SavingsAccountProxy() { return (new ChannelFactory<ISavingsAccount>("tcpSavingsAccount")) .CreateChannel(); }   } }   With that in place, lets get our unit tests going   using System; using System.Diagnostics; using BankDAL.Model; using NUnit.Framework; using ProfileContract;   namespace Client { [TestFixture] public class Tests { private void TransferFundsFromSavingsToCheckingAccount(int customerId, decimal amount) { ProxyFacade.CheckingAccountProxy().DepositAmount(customerId, amount); ProxyFacade.SavingsAccountProxy().WithdrawAmount(customerId, amount); }   private void TransferFundsFromCheckingToSavingsAccount(int customerId, decimal amount) { ProxyFacade.SavingsAccountProxy().DepositAmount(customerId, amount); ProxyFacade.CheckingAccountProxy().WithdrawAmount(customerId, amount); }     [Test] public void CreateAndGetProfileTest() { IProfile profile = ProxyFacade.ProfileProxy(); const string customerName = "Tom"; int customerId = profile.CreateCustomer(customerName, "NJ", new DateTime(1982, 1, 1)).Id; Customer customer = profile.GetCustomer(customerId); Assert.AreEqual(customerName,customer.FullName); }   [Test] public void DepositWithDrawAndTransferAmountTest() { IProfile profile = ProxyFacade.ProfileProxy(); string customerName = "Smith" + DateTime.Now.ToString("HH:mm:ss"); var customer = profile.CreateCustomer(customerName, "NJ", new DateTime(1982, 1, 1)); // Deposit to Savings ProxyFacade.SavingsAccountProxy().DepositAmount(customer.Id, 100); ProxyFacade.SavingsAccountProxy().DepositAmount(customer.Id, 25); Assert.AreEqual(125, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customer.Id)); // Withdraw ProxyFacade.SavingsAccountProxy().WithdrawAmount(customer.Id, 30); Assert.AreEqual(95, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customer.Id));   // Deposit to Checking ProxyFacade.CheckingAccountProxy().DepositAmount(customer.Id, 60); ProxyFacade.CheckingAccountProxy().DepositAmount(customer.Id, 40); Assert.AreEqual(100, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customer.Id)); // Withdraw ProxyFacade.CheckingAccountProxy().WithdrawAmount(customer.Id, 30); Assert.AreEqual(70, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customer.Id));   // Transfer from Savings to Checking TransferFundsFromSavingsToCheckingAccount(customer.Id,10); Assert.AreEqual(85, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customer.Id)); Assert.AreEqual(80, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customer.Id));   // Transfer from Checking to Savings TransferFundsFromCheckingToSavingsAccount(customer.Id, 50); Assert.AreEqual(135, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customer.Id)); Assert.AreEqual(30, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customer.Id)); }   [Test] public void FundTransfersWithOverDraftTest() { IProfile profile = ProxyFacade.ProfileProxy(); string customerName = "Angelina" + DateTime.Now.ToString("HH:mm:ss");   var customerId = profile.CreateCustomer(customerName, "NJ", new DateTime(1972, 1, 1)).Id;   ProxyFacade.SavingsAccountProxy().DepositAmount(customerId, 100); TransferFundsFromSavingsToCheckingAccount(customerId,80); Assert.AreEqual(20, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customerId)); Assert.AreEqual(80, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customerId));   try { TransferFundsFromSavingsToCheckingAccount(customerId,30); } catch (Exception e) { Debug.WriteLine(e.Message); }   Assert.AreEqual(110, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customerId)); Assert.AreEqual(20, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customerId)); } } }   We are creating a new instance of the channel for every operation, we will look into instance management and how creating a new instance of channel affects it in subsequent articles. The first two test cases deals with creation of Customer, deposit and withdraw of month between accounts. The last case, FundTransferWithOverDraftTest() is interesting. Customer starts with depositing $100 in SavingsAccount followed by transfer of $80 in to checking account resulting in $20 in savings account.  Customer then initiates $30 transfer from Savings to Checking resulting in overdraft exception on Savings with $30 being deposited to Checking. As we are not running both the requests in transactions the customer ends up with more amount than what he started with $100. In subsequent posts we will look into transactions handling.  Make sure the ServiceHost project is set as start up project and start the solution. Run the test cases either from NUnit client or TestDriven.Net/Resharper which ever is your favorite tool. Make sure you have updated the data base connection string in the ServiceHost config file to point to your local database

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• Adventures in MVVM &ndash; ViewModel Location and Creation

  - by Brian Genisio's House Of Bilz

  More Adventures in MVVM In this post, I am going to explore how I prefer to attach ViewModels to my Views.  I have published the code to my ViewModelSupport project on CodePlex in case you'd like to see how it works along with some examples.  Some History My approach to View-First ViewModel creation has evolved over time.  I have constructed ViewModels in code-behind.  I have instantiated ViewModels in the resources sectoin of the view. I have used Prism to resolve ViewModels via Dependency Injection. I have created attached properties that use Dependency Injection containers underneath.  Of all these approaches, I continue to find issues either in composability, blendability or maintainability.  Laurent Bugnion came up with a pretty good approach in MVVM Light Toolkit with his ViewModelLocator, but as John Papa points out, it has maintenance issues.  John paired up with Glen Block to make the ViewModelLocator more generic by using MEF to compose ViewModels.  It is a great approach, but I don’t like baking in specific resolution technologies into the ViewModelSupport project. I bring these people up, not to name drop, but to give them credit for the place I finally landed in my journey to resolve ViewModels.  I have come up with my own version of the ViewModelLocator that is both generic and container agnostic.  The solution is blendable, configurable and simple to use.  Use any resolution mechanism you want: MEF, Unity, Ninject, Activator.Create, Lookup Tables, new, whatever. How to use the locator 1. Create a class to contain your resolution configuration: public class YourViewModelResolver: IViewModelResolver { private YourFavoriteContainer container = new YourFavoriteContainer(); public YourViewModelResolver() { // Configure your container } public object Resolve(string viewModelName) { return container.Resolve(viewModelName); } } Examples of doing this are on CodePlex for MEF, Unity and Activator.CreateInstance. 2. Create your ViewModelLocator with your custom resolver in App.xaml: <VMS:ViewModelLocator x:Key="ViewModelLocator"> <VMS:ViewModelLocator.Resolver> <local:YourViewModelResolver /> </VMS:ViewModelLocator.Resolver> </VMS:ViewModelLocator> 3. Hook up your data context whenever you want a ViewModel (WPF): <Border DataContext="{Binding YourViewModelName, Source={StaticResource ViewModelLocator}}"> This example uses dynamic properties on the ViewModelLocator and passes the name to your resolver to figure out how to compose it. 4. What about Silverlight? Good question.  You can't bind to dynamic properties in Silverlight 4 (crossing my fingers for Silverlight 5), but you CAN use string indexing: <Border DataContext="{Binding [YourViewModelName], Source={StaticResource ViewModelLocator}}"> But, as John Papa points out in his article, there is a silly bug in Silverlight 4 (as of this writing) that will call into the indexer 6 times when it binds.  While this is little more than a nuisance when getting most properties, it can be much more of an issue when you are resolving ViewModels six times.  If this gets in your way, the solution (as pointed out by John), is to use an IndexConverter (instantiated in App.xaml and also included in the project): <Border DataContext="{Binding Source={StaticResource ViewModelLocator}, Converter={StaticResource IndexConverter}, ConverterParameter=YourViewModelName}"> It is a bit uglier than the WPF version (this method will also work in WPF if you prefer), but it is still not all that bad.  Conclusion This approach works really well (I suppose I am a bit biased).  It allows for composability from any mechanisim you choose.  It is blendable (consider serving up different objects in Design Mode if you wish... or different constructors… whatever makes sense to you).  It works in Cider.  It is configurable.  It is flexible.  It is the best way I have found to manage View-First ViewModel hookups.  Thanks to the guys mentioned in this article for getting me to something I love using.  Enjoy.

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• Silverlight Cream for January 16, 2011 -- #1029

  - by Dave Campbell

  In this Issue: Michael Washington, Jesse Liberty, Deborah Kurata(-2-, -3-, -4-), Sergey Barskiy(-2-), Miroslav Nedyalkov, Jeff Prosise, and Matthias Shapiro(-2-). Above the Fold: Silverlight: "Building a Multi-Page Silverlight LOB Application" Deborah Kurata WP7: "Windows Phone 7 [Controls] Project" Sergey Barskiy Sketchflow: "Sketchflow To Final" Michael Washington From SilverlightCream.com: Sketchflow To Final Check out this post by Michael Washington detailing the Sketchflow he did of his app, and how the final result tracks amazingly well. Windows Phone From Scratch #19 – MVVM Light Toolkit Soup To Nuts #4 Continuing to try to catch up to Jesse Liberty is this post, number 19 in the Windows Phone series and the 4th in that series about MVVMLight, and discussing binding a collection in the ViewModel to a ListBox in the view. Building a Multi-Page Silverlight LOB Application Deborah Kurata has the first 4 parts up (in 2 days) in a 6-part tutorial series she's doing on building a Silverlight LOB app. The first post was an intro and link to the rest as they become available. This 2nd post is getting the app newed up and making sure you've got your head wrapped around multiple pages. Theming a Silverlight Application using Existing Themes Deborah Kurata's next part is about getting started with themes in your app using the themes provided in the toolkit specifically. Theming a Silverlight Application using Custom Themes Deborah Kurata's next tutorial in the series is also about themes, but this time it's about custom themes... or rather customized from a 'standard' one in this case. Adding a New Page to a Multi-Page Silverlight Application Deborah Kurata's last available post in the tutorial series is this one on adding a new page to the app. Windows Phone 7 Project Sergey Barskiy has a pair of posts up about a calendar control that he is building and has out on CodePlex... nice-looking control too! Windows Phone 7 Controls Project Update Sergey Barskiy's second post is an update to the calendar... the biggest update being the ability to use the Toolkit context menu. How to Create Ad Rotator with Telerik TransitionControl and CoverFlow control for Silverlight Miroslav Nedyalkov uses the Telerik TransitionControl and CoverFlow controls to produce a great-looking ad rotator using any ContentControl or ListBox... very nice demo on the page.... Building Touch Interfaces for Windows Phones, Part 2 Jeff Prosise has part 2 of his tutorial series on WP7 Touch Interfaces up... and he's processing touch events directly in this one. Fixing the ListPicker / ScrollViewer Problem in Windows Phone 7 Matthias Shapiro has a couple of posts out that I've missed... this one is on an issue with ListPickers in a ScrollViewer where the listpicker gets hit rather than the scroll, and of course he has a work-around... but you'll need the source for the ListPicker to do it. Embedding a Sound File in Windows Phone 7 app (Silverlight) The next post by Matthias Shapiro is an explanation of embedding a sound file in a WP7 app with 2 conditions: 1) it downloads with your app, and 2) it plays no matter what. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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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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• Big Data – Basics of Big Data Architecture – Day 4 of 21

  - by Pinal Dave

  In yesterday’s blog post we understood how Big Data evolution happened. Today we will understand basics of the Big Data Architecture. Big Data Cycle Just like every other database related applications, bit data project have its development cycle. Though three Vs (link) for sure plays an important role in deciding the architecture of the Big Data projects. Just like every other project Big Data project also goes to similar phases of the data capturing, transforming, integrating, analyzing and building actionable reporting on the top of  the data. While the process looks almost same but due to the nature of the data the architecture is often totally different. Here are few of the question which everyone should ask before going ahead with Big Data architecture. Questions to Ask How big is your total database? What is your requirement of the reporting in terms of time – real time, semi real time or at frequent interval? How important is the data availability and what is the plan for disaster recovery? What are the plans for network and physical security of the data? What platform will be the driving force behind data and what are different service level agreements for the infrastructure? This are just basic questions but based on your application and business need you should come up with the custom list of the question to ask. As I mentioned earlier this question may look quite simple but the answer will not be simple. When we are talking about Big Data implementation there are many other important aspects which we have to consider when we decide to go for the architecture. Building Blocks of Big Data Architecture It is absolutely impossible to discuss and nail down the most optimal architecture for any Big Data Solution in a single blog post, however, we can discuss the basic building blocks of big data architecture. Here is the image which I have built to explain how the building blocks of the Big Data architecture works. Above image gives good overview of how in Big Data Architecture various components are associated with each other. In Big Data various different data sources are part of the architecture hence extract, transform and integration are one of the most essential layers of the architecture. Most of the data is stored in relational as well as non relational data marts and data warehousing solutions. As per the business need various data are processed as well converted to proper reports and visualizations for end users. Just like software the hardware is almost the most important part of the Big Data Architecture. In the big data architecture hardware infrastructure is extremely important and failure over instances as well as redundant physical infrastructure is usually implemented. NoSQL in Data Management NoSQL is a very famous buzz word and it really means Not Relational SQL or Not Only SQL. This is because in Big Data Architecture the data is in any format. It can be unstructured, relational or in any other format or from any other data source. To bring all the data together relational technology is not enough, hence new tools, architecture and other algorithms are invented which takes care of all the kind of data. This is collectively called NoSQL. Tomorrow Next four days we will answer the Buzz Words – Hadoop. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• Is SugarCRM really adequate for custom development (or adequate at all)? [closed]

  - by dukeofgaming

  Have you used SugarCRM for custom development successfully?, if so, have you done it programmatically or through the Module Builder? Were you successful? If not, why? I used SugarCRM for a project about two years ago, I ran into errors from the very installation, having to hack the actual installation file to deploy the software in the server and other erros that I can't recall now. Two years after, I'm picking it up for a project once again. I'm feeling like I should have developed the whole thing from scratch myself. Some examples: I couldn't install it in the server (again). I had to install it locally, then copy the files and database over to the server and manually edit the config file. Constantly getting deployment errors from the module builder. One reason is SugarCRM keeps creating a record in the upgrade_history table for a file that does not exist, I keep deleting such record and it keeps coming back corrupt. I get other deployment errors, but have not figured them out. then I have to rollback all files and database to try again. I deleted a custom module with relationships, the relationships stayed in the other modules and cannot be deleted anymore, PHP warnings all over the place. Quick create for custom modules does not appear, hack needed. Its whole cache directory is a joke, permanent data/files are stored there. The module builder interface disappears required fields. Edit the wrong thing, module builder won't deploy again, then pray Quick Repair and/or Rebuild Relationships do the trick. My impression of SugarCRM now is that, regardless of its pretty exterior and apparent functionality, it is a very low quality piece of software. This even scared me more: http://amplicate.com/hate/sugarcrm; a quote: I wis this info had been available when I tried to implement it 2 years ago... I searched high and low and the only info I found was positive. Yes, it's a piece of crap. The community edition was full of bugs... nothing worked. Essentially I got fired for implementing it. I'm glad though, because now I work for myself, am much happier and make more money... so, I should really thank SugarCRM for sucking so much I guess! I figured that perhaps some of you have had similar experiences, and have either sticked with SugarCRM or moved on to another solution. I'm very interested in knowing what your resolutions were -or your current situations are- to make up my own mind, since the project I'm working on is long term and I'm feeling SugarCRM will be more an obstacle than an aid. After further failed attempts to continue using this software I continued to stumble upon dead-ends when using the module editor, I could only recover from this errors by using version control. We are now moving on to a custom implementation using Symfony; perhaps if we were using it with its out-of-the-box modules we would have sticked with it.

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• AIX Checklist for stable obiee deployment

  - by user554629

  Common AIX configuration issues     ( last updated 27 Aug 2012 ) OBIEE is a complicated system with many moving parts and connection points.The purpose of this article is to provide a checklist to discuss OBIEE deployment with your systems administrators. The information in this article is time sensitive, and updated as I discover new  issues or details. What makes OBIEE different? When Tech Support suggests AIX component upgrades to a stable, locked-down production AIX environment, it is common to get "push back".  "Why is this necessary?  We aren't we seeing issues with other software?"It's a fair question that I have often struggled to answer; here are the talking points: OBIEE is memory intensive.  It is the entire purpose of the software to trade memory for repetitive, more expensive database requests across a network. OBIEE is implemented in C++ and is very dependent on the C++ runtime to behave correctly. OBIEE is aggressively thread efficient;  if atomic operations on a particular architecture do not work correctly, the software crashes. OBIEE dynamically loads third-party database client libraries directly into the nqsserver process.  If the library is not thread-safe, or corrupts process memory the OBIEE crash happens in an unrelated part of the code.  These are extremely difficult bugs to find. OBIEE software uses 99% common source across multiple platforms:  Windows, Linux, AIX, Solaris and HPUX.  If a crash happens on only one platform, we begin to suspect other factors.  load intensity, system differences, configuration choices, hardware failures.  It is rare to have a single product require so many diverse technical skills.   My role in support is to understand system configurations, performance issues, and crashes.   An analyst trained in Business Analytics can't be expected to know AIX internals in the depth required to make configuration choices.  Here are some guidelines. AIX C++ Runtime must be at  version 11.1.0.4$ lslpp -L | grep xlC.aixobiee software will crash if xlC.aix.rte is downlevel;  this is not a "try it" suggestion.Nov 2011 11.1.0.4 version  is appropriate for all AIX versions ( 5, 6, 7 )Download from here:https://www-304.ibm.com/support/docview.wss?uid=swg24031426 No reboot is necessary to install, it can even be installed while applications are using the current version.Restart the apps, and they will pick up the latest version. AIX 5.3 Technology Level 12 is required when running on Power5,6,7 processorsAIX 6.1 was introduced with the newer Power chips, and we have seen no issues with 6.1 or 7.1 versions.Customers with an unstable deployment, dozens of unexplained crashes, became stable after the upgrade.If your AIX system is 5.3, the minimum TL level should be at or higher than this:$ oslevel -s  5300-12-03-1107IBM typically supports only the two latest versions of AIX ( 6.1 and 7.1, for example).  AIX 5.3 is still supported and popular running in an LPAR. obiee userid limits$ ulimit -Ha  ( hard limits )$ ulimit -a   ( default limits )core file size (blocks)     unlimiteddata seg size (kbytes)      unlimitedfile size (blocks)          unlimitedmax memory size (kbytes)    unlimitedopen files                  10240 cpu time (seconds)          unlimitedvirtual memory (kbytes)     unlimitedIt is best to establish the values in /etc/security/limitsroot user is needed to observe and modify this file.If you modify a limit, you will need to relog in to change it again.  For example,$ ulimit -c 0$ ulimit -c 2097151cannot modify limit: Operation not permitted$ ulimit -c unlimited$ ulimit -c0There are only two meaningful values for ulimit -c ; zero or unlimited.Anything else is likely to produce a truncated core file that cannot be analyzed. Deploy 32-bit or 64-bit ?Early versions of OBIEE offered 32-bit or 64-bit choice to AIX customers.The 32-bit choice was needed if a database vendor did not supply a 64-bit client library.That's no longer an issue and beginning with OBIEE 11, 32-bit code is no longer shipped.A common error that leads to "out of memory" conditions to to accept the 32-bit memory configuration choices on 64-bit deployments.  The significant configuration choices are: Maximum process data (heap) size is in an AIX environment variableLDR_CNTRL=IGNOREUNLOAD@LOADPUBLIC@PREREAD_SHLIB@MAXDATA=0x... Two thread stack sizes are made in obiee NQSConfig.INI[ SERVER ]SERVER_THREAD_STACK_SIZE = 0;DB_GATEWAY_THREAD_STACK_SIZE = 0; Sort memory in NQSConfig.INI[ GENERAL ]SORT_MEMORY_SIZE = 4 MB ;SORT_BUFFER_INCREMENT_SIZE = 256 KB ; Choosing a value for MAXDATA:0x080000000  2GB Default maximum 32-bit heap size ( 8 with 7 zeros )0x100000000  4GB 64-bit breaking even with 32-bit ( 1 with 8 zeros )0x200000000  8GB 64-bit double 32-bit max0x400000000 16GB 64-bit safetyUsing 2GB heap size for a 64-bit process will almost certainly lead to an out-of-memory situation.Registers are twice as big ... consume twice as much memory in the heap.Upgrading to a 4GB heap for a 64-bit process is just "breaking even" with 32-bit.A 32-bit process is constrained by the 32-bit virtual addressing limits.  Heap memory is used for dynamic requirements of obiee software, thread stacks for each of the configured threads, and sometimes for shared libraries. 64-bit processes are not constrained in this way;  extra heap space can be configured for safety against a query that might create a sudden requirement for excessive storage.  If the storage is not available, this query might crash the whole server and disrupt existing users.There is no performance penalty on AIX for configuring more memory than required;  extra memory can be configured for safety.  If there are no other considerations, start with 8GB.Choosing a value for Thread Stack size:zero is the value documented to select an appropriate default for thread stack size.  My preference is to change this to an absolute value, even if you intend to use the documented default;  it provides better documentation and removes the "surprise" factor.There are two thread types that can be configured. GATEWAY is used by a thread pool to call a database client library to establish a DB connection.The default size is 256KB;  many customers raise this to 512KB ( no performance penalty for over-configuring ). This value must be set to 1 MB if Teradata connections are used. SERVER threads are used to run queries.  OBIEE uses recursive algorithms during the analysis of query structures which can consume significant thread stack storage.  It's difficult to provide guidance on a value that depends on data and complexity.  The general notion is to provide more space than you think you need,  "double down" and increase the value if you run out, otherwise inspect the query to understand why it is too complex for the thread stack.  There are protections built into the software to abort a single user query that is too complex, but the algorithms don't cover all situations.256 KB  The default 32-bit stack size.  Many customers increased this to 512KB on 32-bit.  A 64-bit server is very likely to crash with this value;  the stack contains mostly register values, which are twice as big.512 KB  The documented 64-bit default.  Some early releases of obiee didn't set this correctly, resulting in 256KB stacks.1 MB  The recommended 64-bit setting.  If your system only ever uses 512KB of stack space, there is no performance penalty for using 1MB stack size.2 MB  Many large customers use this value for safety.  No performance penalty.nqscheduler does not use the NQSConfig.INI file to set thread stack size.If this process crashes because the thread stack is too small, use this to set 2MB:export OBI_BACKGROUND_STACK_SIZE=2048 Shared libraries are not (shared) When application libraries are loaded at run-time, AIX makes a decision on whether to load the libraries in a "public" memory segment.  If the filesystem library permissions do not have the "Read-Other" permission bit, AIX loads the library into private process memory with two significant side-effects:* The libraries reduce the heap storage available.      Might be significant in 32-bit processes;  irrelevant in 64-bit processes.* Library code is loaded into multiple real pages for execution;  one copy for each process.Multiple execution images is a significant issue for both 32- and 64-bit processes.The "real memory pages" saved by using public memory segments is a minor concern.  Today's machines typically have plenty of real memory.The real problem with private copies of libraries is that they consume processor cache blocks, which are limited.   The same library instructions executing in different real pages will cause memory delays as the i-cache ( instruction cache 128KB blocks) are refreshed from real memory.   Performance loss because instructions are delayed is something that is difficult to measure without access to low-level cache fault data.   The machine just appears to be running slowly for no observable reason.This is an easy problem to detect, and an easy problem to correct.Detection:  "genld -l" AIX command produces a list of the libraries used by each process and the AIX memory address where they are loaded.32-bit public segment is 13 ( "dxxxxxxx" ).   private segments are 2-a.64-bit public segment is 9 ( "9xxxxxxxxxxxxxxx") ; private segment is 8.genld -l | grep -v ' d| 9' | sort +2provides a list of privately loaded libraries. Repair: chmod o+r <libname>AIX shared libraries will have a suffix of ".so" or ".a".Another technique is to change all libraries in a selected directory to repair those that might not be currently loaded.   The usual directories that need repair are obiee code, httpd code and plugins, database client libraries and java.chmod o+r /shr/dir/*.a /shr/dir/*.so Configure your system for diagnosticsProduction systems shouldn't crash, and yet bad things happen to good software.If obiee software crashes and produces a core, you should configure your system for reliable transfer of the failing conditions to Oracle Tech Support.  Here's what we need to be able to diagnose a core file from your system.* fullcore enabled. chdev -lsys0 -a fullcore=true* core naming enabled. chcore -n on -d* ulimit must not truncate core. see item 3.* pstack.sh is used to capture core documentation.* obidoc is used to capture current AIX configuration.* snapcore  AIX utility captures core and libraries. Use the proper syntax. $ snapcore -r corename executable-fullpath   /tmp/snapcore will contain the .pax.Z output file.  It is compressed.* If cores are directed to a common directory, ensure obiee userid can write to the directory.  ( chcore -p /cores -d ; chmod 777 /cores )The filesystem must have sufficient space to hold a crashing obiee application.Use:  df -k  Check the "Free" column ( not "% Used" )  8388608 is 8GB. Disable Oracle Client Library signal handlingThe Oracle DB Client Library is frequently distributed with the sqlplus development kit.By default, the library enables a signal handler, which will document a call stack if the application crashes.   The signal handler is not needed, and definitely disruptive to obiee diagnostics.   It needs to be disabled.   sqlnet.ora is typically located at:   $ORACLE_HOME/network/admin/sqlnet.oraAdd this line at the top of the file:   DIAG_SIGHANDLER_ENABLED=FALSE Disable async query in the RPD connection pool.This might be an obiee 10.1.3.4 issue only ( still checking  )."async query" must be disabled in the connection pools.It was designed to enable query cancellation to a database, and turned out to have too many edge conditions in normal communication that produced random corruption of data and crashes.  Please ensure it is turned off in the RPD. Check AIX error report (errpt).Errors external to obiee applications can trigger crashes.  $ /bin/errpt -aHardware errors ( firmware, adapters, disks ) should be reported to IBM support.All application core files are recorded by AIX;  the most recent ones are listed first. Reserved for something important to say.

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• Seeking on a Heap, and Two Useful DMVs

  - by Paul White

  So far in this mini-series on seeks and scans, we have seen that a simple ‘seek’ operation can be much more complex than it first appears.  A seek can contain one or more seek predicates – each of which can either identify at most one row in a unique index (a singleton lookup) or a range of values (a range scan).  When looking at a query plan, we will often need to look at the details of the seek operator in the Properties window to see how many operations it is performing, and what type of operation each one is.  As you saw in the first post in this series, the number of hidden seeking operations can have an appreciable impact on performance. Measuring Seeks and Scans I mentioned in my last post that there is no way to tell from a graphical query plan whether you are seeing a singleton lookup or a range scan.  You can work it out – if you happen to know that the index is defined as unique and the seek predicate is an equality comparison, but there’s no separate property that says ‘singleton lookup’ or ‘range scan’.  This is a shame, and if I had my way, the query plan would show different icons for range scans and singleton lookups – perhaps also indicating whether the operation was one or more of those operations underneath the covers. In light of all that, you might be wondering if there is another way to measure how many seeks of either type are occurring in your system, or for a particular query.  As is often the case, the answer is yes – we can use a couple of dynamic management views (DMVs): sys.dm_db_index_usage_stats and sys.dm_db_index_operational_stats. Index Usage Stats The index usage stats DMV contains counts of index operations from the perspective of the Query Executor (QE) – the SQL Server component that is responsible for executing the query plan.  It has three columns that are of particular interest to us: user_seeks – the number of times an Index Seek operator appears in an executed plan user_scans – the number of times a Table Scan or Index Scan operator appears in an executed plan user_lookups – the number of times an RID or Key Lookup operator appears in an executed plan An operator is counted once per execution (generating an estimated plan does not affect the totals), so an Index Seek that executes 10,000 times in a single plan execution adds 1 to the count of user seeks.  Even less intuitively, an operator is also counted once per execution even if it is not executed at all.  I will show you a demonstration of each of these things later in this post. Index Operational Stats The index operational stats DMV contains counts of index and table operations from the perspective of the Storage Engine (SE).  It contains a wealth of interesting information, but the two columns of interest to us right now are: range_scan_count – the number of range scans (including unrestricted full scans) on a heap or index structure singleton_lookup_count – the number of singleton lookups in a heap or index structure This DMV counts each SE operation, so 10,000 singleton lookups will add 10,000 to the singleton lookup count column, and a table scan that is executed 5 times will add 5 to the range scan count. The Test Rig To explore the behaviour of seeks and scans in detail, we will need to create a test environment.  The scripts presented here are best run on SQL Server 2008 Developer Edition, but the majority of the tests will work just fine on SQL Server 2005.  A couple of tests use partitioning, but these will be skipped if you are not running an Enterprise-equivalent SKU.  Ok, first up we need a database: USE master; GO IF DB_ID('ScansAndSeeks') IS NOT NULL DROP DATABASE ScansAndSeeks; GO CREATE DATABASE ScansAndSeeks; GO USE ScansAndSeeks; GO ALTER DATABASE ScansAndSeeks SET ALLOW_SNAPSHOT_ISOLATION OFF ; ALTER DATABASE ScansAndSeeks SET AUTO_CLOSE OFF, AUTO_SHRINK OFF, AUTO_CREATE_STATISTICS OFF, AUTO_UPDATE_STATISTICS OFF, PARAMETERIZATION SIMPLE, READ_COMMITTED_SNAPSHOT OFF, RESTRICTED_USER ; Notice that several database options are set in particular ways to ensure we get meaningful and reproducible results from the DMVs.  In particular, the options to auto-create and update statistics are disabled.  There are also three stored procedures, the first of which creates a test table (which may or may not be partitioned).  The table is pretty much the same one we used yesterday: The table has 100 rows, and both the key_col and data columns contain the same values – the integers from 1 to 100 inclusive.  The table is a heap, with a non-clustered primary key on key_col, and a non-clustered non-unique index on the data column.  The only reason I have used a heap here, rather than a clustered table, is so I can demonstrate a seek on a heap later on.  The table has an extra column (not shown because I am too lazy to update the diagram from yesterday) called padding – a CHAR(100) column that just contains 100 spaces in every row.  It’s just there to discourage SQL Server from choosing table scan over an index + RID lookup in one of the tests. The first stored procedure is called ResetTest: CREATE PROCEDURE dbo.ResetTest @Partitioned BIT = 'false' AS BEGIN SET NOCOUNT ON ; IF OBJECT_ID(N'dbo.Example', N'U') IS NOT NULL BEGIN DROP TABLE dbo.Example; END ; -- Test table is a heap -- Non-clustered primary key on 'key_col' CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, padding CHAR(100) NOT NULL DEFAULT SPACE(100), CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col) ) ; IF @Partitioned = 'true' BEGIN -- Enterprise, Trial, or Developer -- required for partitioning tests IF SERVERPROPERTY('EngineEdition') = 3 BEGIN EXECUTE (' DROP TABLE dbo.Example ; IF EXISTS ( SELECT 1 FROM sys.partition_schemes WHERE name = N''PS'' ) DROP PARTITION SCHEME PS ; IF EXISTS ( SELECT 1 FROM sys.partition_functions WHERE name = N''PF'' ) DROP PARTITION FUNCTION PF ; CREATE PARTITION FUNCTION PF (INTEGER) AS RANGE RIGHT FOR VALUES (20, 40, 60, 80, 100) ; CREATE PARTITION SCHEME PS AS PARTITION PF ALL TO ([PRIMARY]) ; CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, padding CHAR(100) NOT NULL DEFAULT SPACE(100), CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col) ) ON PS (key_col); '); END ELSE BEGIN RAISERROR('Invalid SKU for partition test', 16, 1); RETURN; END; END ; -- Non-unique non-clustered index on the 'data' column CREATE NONCLUSTERED INDEX [IX dbo.Example data] ON dbo.Example (data) ; -- Add 100 rows INSERT dbo.Example WITH (TABLOCKX) ( key_col, data ) SELECT key_col = V.number, data = V.number FROM master.dbo.spt_values AS V WHERE V.[type] = N'P' AND V.number BETWEEN 1 AND 100 ; END; GO The second stored procedure, ShowStats, displays information from the Index Usage Stats and Index Operational Stats DMVs: CREATE PROCEDURE dbo.ShowStats @Partitioned BIT = 'false' AS BEGIN -- Index Usage Stats DMV (QE) SELECT index_name = ISNULL(I.name, I.type_desc), scans = IUS.user_scans, seeks = IUS.user_seeks, lookups = IUS.user_lookups FROM sys.dm_db_index_usage_stats AS IUS JOIN sys.indexes AS I ON I.object_id = IUS.object_id AND I.index_id = IUS.index_id WHERE IUS.database_id = DB_ID(N'ScansAndSeeks') AND IUS.object_id = OBJECT_ID(N'dbo.Example', N'U') ORDER BY I.index_id ; -- Index Operational Stats DMV (SE) IF @Partitioned = 'true' SELECT index_name = ISNULL(I.name, I.type_desc), partitions = COUNT(IOS.partition_number), range_scans = SUM(IOS.range_scan_count), single_lookups = SUM(IOS.singleton_lookup_count) FROM sys.dm_db_index_operational_stats ( DB_ID(N'ScansAndSeeks'), OBJECT_ID(N'dbo.Example', N'U'), NULL, NULL ) AS IOS JOIN sys.indexes AS I ON I.object_id = IOS.object_id AND I.index_id = IOS.index_id GROUP BY I.index_id, -- Key I.name, I.type_desc ORDER BY I.index_id; ELSE SELECT index_name = ISNULL(I.name, I.type_desc), range_scans = SUM(IOS.range_scan_count), single_lookups = SUM(IOS.singleton_lookup_count) FROM sys.dm_db_index_operational_stats ( DB_ID(N'ScansAndSeeks'), OBJECT_ID(N'dbo.Example', N'U'), NULL, NULL ) AS IOS JOIN sys.indexes AS I ON I.object_id = IOS.object_id AND I.index_id = IOS.index_id GROUP BY I.index_id, -- Key I.name, I.type_desc ORDER BY I.index_id; END; The final stored procedure, RunTest, executes a query written against the example table: CREATE PROCEDURE dbo.RunTest @SQL VARCHAR(8000), @Partitioned BIT = 'false' AS BEGIN -- No execution plan yet SET STATISTICS XML OFF ; -- Reset the test environment EXECUTE dbo.ResetTest @Partitioned ; -- Previous call will throw an error if a partitioned -- test was requested, but SKU does not support it IF @@ERROR = 0 BEGIN -- IO statistics and plan on SET STATISTICS XML, IO ON ; -- Test statement EXECUTE (@SQL) ; -- Plan and IO statistics off SET STATISTICS XML, IO OFF ; EXECUTE dbo.ShowStats @Partitioned; END; END; The Tests The first test is a simple scan of the heap table: EXECUTE dbo.RunTest @SQL = 'SELECT * FROM Example'; The top result set comes from the Index Usage Stats DMV, so it is the Query Executor’s (QE) view.  The lower result is from Index Operational Stats, which shows statistics derived from the actions taken by the Storage Engine (SE).  We see that QE performed 1 scan operation on the heap, and SE performed a single range scan.  Let’s try a single-value equality seek on a unique index next: EXECUTE dbo.RunTest @SQL = 'SELECT key_col FROM Example WHERE key_col = 32'; This time we see a single seek on the non-clustered primary key from QE, and one singleton lookup on the same index by the SE.  Now for a single-value seek on the non-unique non-clustered index: EXECUTE dbo.RunTest @SQL = 'SELECT data FROM Example WHERE data = 32'; QE shows a single seek on the non-clustered non-unique index, but SE shows a single range scan on that index – not the singleton lookup we saw in the previous test.  That makes sense because we know that only a single-value seek into a unique index is a singleton seek.  A single-value seek into a non-unique index might retrieve any number of rows, if you think about it.  The next query is equivalent to the IN list example seen in the first post in this series, but it is written using OR (just for variety, you understand): EXECUTE dbo.RunTest @SQL = 'SELECT data FROM Example WHERE data = 32 OR data = 33'; The plan looks the same, and there’s no difference in the stats recorded by QE, but the SE shows two range scans.  Again, these are range scans because we are looking for two values in the data column, which is covered by a non-unique index.  I’ve added a snippet from the Properties window to show that the query plan does show two seek predicates, not just one.  Now let’s rewrite the query using BETWEEN: EXECUTE dbo.RunTest @SQL = 'SELECT data FROM Example WHERE data BETWEEN 32 AND 33'; Notice the seek operator only has one predicate now – it’s just a single range scan from 32 to 33 in the index – as the SE output shows.  For the next test, we will look up four values in the key_col column: EXECUTE dbo.RunTest @SQL = 'SELECT key_col FROM Example WHERE key_col IN (2,4,6,8)'; Just a single seek on the PK from the Query Executor, but four singleton lookups reported by the Storage Engine – and four seek predicates in the Properties window.  On to a more complex example: EXECUTE dbo.RunTest @SQL = 'SELECT * FROM Example WITH (INDEX([PK dbo.Example key_col])) WHERE key_col BETWEEN 1 AND 8'; This time we are forcing use of the non-clustered primary key to return eight rows.  The index is not covering for this query, so the query plan includes an RID lookup into the heap to fetch the data and padding columns.  The QE reports a seek on the PK and a lookup on the heap.  The SE reports a single range scan on the PK (to find key_col values between 1 and 8), and eight singleton lookups on the heap.  Remember that a bookmark lookup (RID or Key) is a seek to a single value in a ‘unique index’ – it finds a row in the heap or cluster from a unique RID or clustering key – so that’s why lookups are always singleton lookups, not range scans. Our next example shows what happens when a query plan operator is not executed at all: EXECUTE dbo.RunTest @SQL = 'SELECT key_col FROM Example WHERE key_col = 8 AND @@TRANCOUNT < 0'; The Filter has a start-up predicate which is always false (if your @@TRANCOUNT is less than zero, call CSS immediately).  The index seek is never executed, but QE still records a single seek against the PK because the operator appears once in an executed plan.  The SE output shows no activity at all.  This next example is 2008 and above only, I’m afraid: EXECUTE dbo.RunTest @SQL = 'SELECT * FROM Example WHERE key_col BETWEEN 1 AND 30', @Partitioned = 'true'; This is the first example to use a partitioned table.  QE reports a single seek on the heap (yes – a seek on a heap), and the SE reports two range scans on the heap.  SQL Server knows (from the partitioning definition) that it only needs to look at partitions 1 and 2 to find all the rows where key_col is between 1 and 30 – the engine seeks to find the two partitions, and performs a range scan seek on each partition. The final example for today is another seek on a heap – try to work out the output of the query before running it! EXECUTE dbo.RunTest @SQL = 'SELECT TOP (2) WITH TIES * FROM Example WHERE key_col BETWEEN 1 AND 50 ORDER BY $PARTITION.PF(key_col) DESC', @Partitioned = 'true'; Notice the lack of an explicit Sort operator in the query plan to enforce the ORDER BY clause, and the backward range scan. © 2011 Paul White email: [email protected] twitter: @SQL_Kiwi

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• CodePlex Daily Summary for Saturday, December 11, 2010

  CodePlex Daily Summary for Saturday, December 11, 2010Popular ReleasesEnhSim: EnhSim 2.2.1 ALPHA: 2.2.1 ALPHAThis release adds in the changes for 4.03a. at level 85 To use this release, you must have the Microsoft Visual C++ 2010 Redistributable Package installed. This can be downloaded from http://www.microsoft.com/downloads/en/details.aspx?FamilyID=A7B7A05E-6DE6-4D3A-A423-37BF0912DB84 To use the GUI you must have the .NET 4.0 Framework installed. This can be downloaded from http://www.microsoft.com/downloads/en/details.aspx?FamilyID=9cfb2d51-5ff4-4491-b0e5-b386f32c0992 - Updated th...NuGet (formerly NuPack): NuGet 1.0 Release Candidate: NuGet is a free, open source developer focused package management system for the .NET platform intent on simplifying the process of incorporating third party libraries into a .NET application during development. This release is a Visual Studio 2010 extension and contains the the Package Manager Console and the Add Package Dialog. This new build targets the newer feed (http://go.microsoft.com/fwlink/?LinkID=206669) and package format. See http://nupack.codeplex.com/documentation?title=Nuspe...Free Silverlight & WPF Chart Control - Visifire: Visifire Silverlight, WPF Charts v3.6.5 Released: Hi, Today we are releasing final version of Visifire, v3.6.5 with the following new feature: * New property AutoFitToPlotArea has been introduced in DataSeries. AutoFitToPlotArea will bring bubbles inside the PlotArea in order to avoid clipping of bubbles in bubble chart. You can visit Visifire documentation to know more. http://www.visifire.com/visifirechartsdocumentation.php Also this release includes few bug fixes: * Chart threw exception while adding new Axis in Chart using Vi...PHPExcel: PHPExcel 1.7.5 Production: DonationsDonate via PayPal via PayPal. If you want to, we can also add your name / company on our Donation Acknowledgements page. PEAR channelWe now also have a full PEAR channel! Here's how to use it: New installation: pear channel-discover pear.pearplex.net pear install pearplex/PHPExcel Or if you've already installed PHPExcel before: pear upgrade pearplex/PHPExcel The official page can be found at http://pearplex.net. Want to contribute?Please refer the Contribute page.DNN Simple Article: DNNSimpleArticle Module V00.00.03: The initial release of the DNNSimpleArticle module (labelled V00.00.03) There are C# and VB versions of this module for this initial release. No promises that going forward there will be packages for both languages provided for future releases. This module provides the following functionality Create and display articles Display a paged list of articles Articles get created as DNN ContentItems Categorization provided through DNN Taxonomy SEO functionality for article display providi...UOB & ME: UOB_ME 2.5: latest versionAutoLoL: AutoLoL v1.4.3: AutoLoL now supports importing the build pages from Mobafire.com as well! Just insert the url to the build and voila. (For example: http://www.mobafire.com/league-of-legends/build/unforgivens-guide-how-to-build-a-successful-mordekaiser-24061) Stable release of AutoChat (It is still recommended to use with caution and to read the documentation) It is now possible to associate *.lolm files with AutoLoL to quickly open them The selected spells are now displayed in the masteries tab for qu...SubtitleTools: SubtitleTools 1.2: - Added auto insertion of RLE (RIGHT-TO-LEFT EMBEDDING) Unicode character for the RTL languages. - Fixed delete rows issue.PHP Manager for IIS: PHP Manager 1.1 for IIS 7: This is a final stable release of PHP Manager 1.1 for IIS 7. This is a minor incremental release that contains all the functionality available in 53121 plus additional features listed below: Improved detection logic for existing PHP installations. Now PHP Manager detects the location to php.ini file in accordance to the PHP specifications Configuring date.timezone. PHP Manager can automatically set the date.timezone directive which is required to be set starting from PHP 5.3 Ability to ...Algorithmia: Algorithmia 1.1: Algorithmia v1.1, released on December 8th, 2010.SuperSocket, an extensible socket application framework: SuperSocket 1.0 SP1: Fixed bugs: fixed a potential bug that the running state hadn't been updated after socket server stopped fixed a synchronization issue when clearing timeout session fixed a bug in ArraySegmentList fixed a bug on getting configuration valueMy Web Pages Starter Kit: 1.3.1 Production Release (Security HOTFIX): Due to a critical security issue, it's strongly advised to update the My Web Pages Starter Kit to this version. Possible attackers could misuse the image upload to transmit any type of file to the website. If you already have a running version of My Web Pages Starter Kit 1.3.0, you can just replace the ftb.imagegallery.aspx file in the root directory with the one attached to this release.ASP.NET MVC Project Awesome (jQuery Ajax helpers): 1.4: A rich set of helpers (controls) that you can use to build highly responsive and interactive Ajax-enabled Web applications. These helpers include Autocomplete, AjaxDropdown, Lookup, Confirm Dialog, Popup Form, Popup and Pager new stuff: popup WhiteSpaceFilterAttribute tested on mozilla, safari, chrome, opera, ie 9b/8/7/6nopCommerce. ASP.NET open source shopping cart: nopCommerce 1.90: To see the full list of fixes and changes please visit the release notes page (http://www.nopCommerce.com/releasenotes.aspx).TweetSharp: TweetSharp v2.0.0.0 - Preview 4: Documentation for this release may be found at http://tweetsharp.codeplex.com/wikipage?title=UserGuide&referringTitle=Documentation. Note: This code is currently preview quality. Preview 4 ChangesReintroduced fluent interface support via satellite assembly Added entities support, entity segmentation, and ITweetable/ITweeter interfaces for client development Numerous fixes reported by preview users Preview 3 ChangesNumerous fixes and improvements to core engine Twitter API coverage: a...myCollections: Version 1.2: New in version 1.2: Big performance improvement. New Design (Added Outlook style View, New detail view, New Groub By...) Added Sort by Media Added Manage Movie Studio Zoom preference is now saved. Media name are now editable. Added Portuguese version You can now Hide details panel Add support for FLAC tags You can now imports books from BibTex Xml file BugFixingmytrip.mvc (CMS & e-Commerce): mytrip.mvc 1.0.49.0 beta: mytrip.mvc 1.0.49.0 beta web Web for install hosting System Requirements: NET 4.0, MSSQL 2008 or MySql (auto creation table to database) if .\SQLEXPRESS auto creation database (App_Data folder) mytrip.mvc 1.0.49.0 beta src System Requirements: Visual Studio 2010 or Web Deweloper 2010 MSSQL 2008 or MySql (auto creation table to database) if .\SQLEXPRESS auto creation database (App_Data folder) Connector/Net 6.3.4, MVC3 RC WARNING For run and debug mytrip.mvc 1.0.49.0 beta src download and ...Power Assert .NET: Power Assert 1.0.1: Minor bugfixes, added PAssert.Throws method to ensure that an operation throws an exceptionExcelLite: Lite Excel Binaries: "Lite Excel Binaries" contains two required Silverlight DLLs Following samples require reference of the "Excel Lite Binaries" , "Writing Image to Excel" is an example silverlight application for writing silverlight image to excel "Writing Data to Excel" is example application of how to write/export silverlight data to an excel file using Excel Lite "Reading Excel file" is sample application demonstrating excel reading with ExcelLiteMenu and Context Menu for Silverlight 4.0: Silverlight Menu and Context Menu v2.3 Beta: - Added keyboard navigation support with access keys - Shortcuts like Ctrl-Alt-A are now supported(where the browser permits it) - The PopupMenuSeparator is now completely based on the PopupMenuItem class - Moved item manipulation code to a partial class in PopupMenuItemsControl.cs - Moved menu management and keyboard navigation code to the new PopupMenuManager class - Simplified the layout by removing the RootGrid element(all content is now placed in OverlayCanvas and is accessed by the new ...New Projectsbuildandrelease: SCM continuous intergration cruisecontrol.net buildandrelease installer automation testing virtual machine infrastructureContent Link Web Part: The ContentLink webpart works like the ContentEditor webpart in ContentLink mode, but does not require you to configure anonymous access. ContentLink is useful for showing common content stored in a central document library for use across different site-collections.CoralCube: Dieses Projekt hat das Ziel eine gute Core zu entwickeln.CRM_Contabil: Criado para uso em escritórios de contabilidade, onde o cliente faz chamadas p/empresa ou chamadas entre funcionários da própria empresa.A empresa manterá um banco de dados com soluções em respeito a dúvidas do cliente e saberá qual cliente utiliza mais seus serviços.CsvImporter: Csv importer is a robust application to make bulk imports to a MSSQL Database. I'm looking forward to add oracle support. This importer works like many web admin importers,except this let you know the register is inserting in a determinate moment, successful and failed query's.CWS - Client Web Services Framework: Client Web Service is a different concept for script reference at client-side. The idea behind client web services is to abstract the concept of client scripts behind the concept of client services. The script reference process is fully encapsulated inside CWS api. Enjoy!DirectDraw APIs Usage in WinCE and WinMobile: DDrawTest application shows how to use the Hardware layers of display controller of different application processor in WinCE and Windows Mobile devices.EasyMapping: EasyMapping makes OR Mapping Configuration easy, writing code easy The first version only support SQLSever Framework version: 3.5 Language: C# ExcelLite: ExcelLite is a C#/Silverlight library for Silverlight applications that can read and write MS Excel files without COM interaction. You can manipulate MS Excel files totally on client side as this library using Binary excel format to read and write data to excel files.Frozen Bubble XNA: A port of the well known Linux game Frozen Bubble from Perl to c# and XNA. The ported game runs on Windows and Windows Phone 7.GetThatList: With GetThatList people will find an easy way to copy a music playlist and its songs to another location, being another folder or a remote computer. It is designed so that it can be exposed to the final user as an standalone application or a Shell extension for playlist files.lightsurfer: Generate and smooth terrain landshaft easily. C++, DirectX 10 and UI in WPF in perspective.microstockUploader: Uploads multiple JPEG images with additional files (RAW, EPS) to multiple microstocks. Supports FTP resume. Supports buggy routers which drop FTP connection after some timeout.Network Monopolizer: Network Monopolizer is a simple program that monopolizes your network. when run, it will overrun your current network with requests, thus it won't work correctly anymore. It contacts five sites a millisecond. This can be used mainly at an airport.niensiesta: No naps!QScript: QScript is a contract-oriented language that supports runtime contract inference, on-fly object construction, lambdas. The main idea of QScript is to provide maximum functionality with minimum efforts.Sequin Sequence Mining Library: Sequin is an open source sequence mining library written in C#.Sitefinity Controls: Sitefinity Controls is a collection of custom controls developed for Sitefinity that I thought might be useful for others. It is developed in C#.Surfix: Surfix is an open source framework built on top of .net Framework. It Provide a set of capabilities and modules such as: Logging, Extension methods for ado.net entity framework, Localization Module, Security Module and so on. This framework is built on top a database Sql Server,.Umbraco AD and Default Membership Provider: This is a Membership provider for Umbraco. It support AD authentication, but only if the user account is already created by the admin in Umbraco. It also support the default Umbraco user authentication at the same time if desired.Wayne's Financial Tracker: Track your finances with this simple to use tool.Weople: Weople is game developed in XNA by a team of students of the "Politecnico di Milano". Our group will participate with Weople to Imagine Cup 2011.WorldListening: This app is able to get news and blog from websites ,and read it with MS SAPI.WPF Diagramming: Tool for draw diagramsYakeen Network Applications Framework: This project is Network Application Server Simulator and Benchmark for modeling networks applications servers, I'm working on this project right now, any help will be appreciated.

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• MVC Portable Areas &ndash; Deploying Static Files

  - by Steve Michelotti

  This is the second post in a series related to build and deployment considerations as I’ve been exploring MVC Portable Areas: #1 – Using Web Application Project to build portable areas #2 – Conventions for deploying portable area static files #3 – Portable area static files as embedded resources As I’ve been digging more into portable areas, one of the things I’ve liked best is the deployment story which enables my *.aspx, *.ascx pages to be compiled into the assembly as embedded resources rather than having to maintain all those files separately. In traditional web forms, that was always the thing to prevented developers from utilizing *.ascx user controls across projects (see this post for using portable areas in web forms).  However, though the aspx pages are embedded, the supporting static files (e.g., images, css, javascript) are *not*. Most of the demos available online today tend to brush over this issue and focus solely on the aspx side of things. But to create truly robust portable areas, it’s important to have a good story for these supporting files as well.  I’ve been working with two different approaches so far (of course I’d really like to hear if other people are using alternatives). Scenario For the approaches below, the scenario really isn’t that important. It could be something as trivial as this partial view: 1: <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl" %> 2: <img src="<%: Url.Content("~/images/arrow.gif") %>" /> Hello World! The point is that there needs to be careful consideration for *any* scenario that links to an external file such as an image, *.css, *.js, etc. In the example shown above, it uses the Url.Content() method to convert to a relative path. But this method won’t necessary work depending on how you deploy your portable area. One approach to address this issue is to build your portable area project with MSDeploy/WebDeploy so that it is packaged properly before incorporating into the host application. All of the *.cs files are removed and the project is ready for xcopy deployment – however, I do *not* need the “Views” folder since all of the mark up has been compiled into the assembly as embedded resources. Now in the host application we create a folder called “Modules” and deploy any portable areas as sub-folders under that: At this point we can add a simple assembly reference to the Widget1.dll sitting in the Modules\Widget1\bin folder. I can now render the portable image in my view like any other portable area. However, the problem with that is that the view results in this:   It couldn’t find arrow.gif because it looked for /images/arrow.gif and it was *actually* located at /images/Modules/Widget1/images/arrow.gif. One solution is to make the physical location of the portable configurable from the perspective of the host like this: 1: <appSettings> 2: <add key="Widget1" value="Modules\Widget1"/> 3: </appSettings> Using the <appSettings> section is a little cheesy but it could be better formalized into its own section. In fact, if were you willing to rely on conventions (e.g., “Modules\{areaName}”) then then config could be eliminated completely. With this config in place, we could create our own Html helper method called Url.AreaContent() that “wraps” the OOTB Url.Content() method while simply pre-pending the area location path: 1: public static string AreaContent(this UrlHelper urlHelper, string contentPath) 2: { 3: var areaName = (string)urlHelper.RequestContext.RouteData.DataTokens["area"]; 4: var areaPath = (string)ConfigurationManager.AppSettings[areaName]; 5:   6: return urlHelper.Content("~/" + areaPath + "/" + contentPath); With these two items in place, we just change our Url.Content() call to Url.AreaContent() like this: 1: <img src="<%: Url.AreaContent("/images/arrow.gif") %>" /> Hello World! and the arrow.gif now renders correctly:     Since we’re just using our own Url.AreaContent() rather than the built-in Url.Content(), this solution works for images, *.css, *.js, or any externally referenced files.  Additionally, any images referenced inside a css file will work provided it’s a relative reference and not an absolute reference. An alternative to this approach is to build the static file into the assembly as embedded resources themselves. I’ll explore this in another post (linked at the top).

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• Duke's Choice Award Ceremony

  - by Tori Wieldt

  The 2012 Duke's Choice Awards winners and their creative, Java-based technologies and Java community contributions were honored after the Sunday night JavaOne keynotes. Sharat Chander, Group Director for Java Technology Outreach, presented the awards. "Having the community participate directly in both submission and selection truly shows how we are driving exposure of the innovation happening in the Java community," he said. Apache Software Foundation Hadoop Project The Apache Software Foundation’s Hadoop project, written in Java, provides a framework for distributed processing of big data sets across clusters of computers, ranging from a few servers to thousands of machines. This harnessing of large data pools allows organizations to better understand and improve their business. AgroSense Project Improving farming methods to feed a hungry world is the goal of AgroSense, an open source farm information management system built in Java and the NetBeans platform. AgroSense enables farmers, agribusinesses, suppliers and others to develop modular applications that will easily exchange information through a common underlying NetBeans framework. JDuchess Rather than focus on a specific geographic area like most Java User Groups (JUGs), JDuchess fosters the participation of women in the Java community worldwide. The group has more than 500 members in 60 countries, and provides a platform through which women can connect with each other and get involved in all aspects of the Java community. Jelastic, Inc. Moving existing Java applications to the cloud can be a daunting task, but startup Jelastic, Inc. offers the first all-Java platform-as-a-service (PaaS) that enables existing Java applications to be deployed in the cloud without code changes or lock-in. Liquid Robotics Robotics – Liquid Robotics is an ocean data services provider whose Wave Glider technology collects information from the world’s oceans for application in government, science and commercial applications. The organization features the “father of Java” James Gosling as its chief software architect. London Java Community The second user group receiving a Duke’s Choice Award this year, the London Java Community (LJC) and its users have been active in the OpenJDK, the Java Community Process (JCP) and other efforts within the global Java community. NATO The first-ever Community Choice Award goes to the MASE Integrated Console Environment (MICE) in use at NATO. Built in Java on the NetBeans platform, MICE provides a high-performance visualization environment for conducting air defense and battle-space operations. Parleys.com E-learning specialist Parleys.com, based in Brussels, Belgium, uses Java technologies to bring online classes and full IT conferences to desktops, laptops, tablets and mobile devices. Parleys.com has hosted more than 1,700 conferences—including Devoxx and JavaOne—for more than 800,000 unique visitors. Student Nokia Developer Group This year’s student winner, Ram Kashyap, is the founder and president of the Nokia Student Network, and was profiled in the “The New Java Developers” feature in the March/April 2012 issue of Java Magazine. Since then, Ram has maintained a hectic pace, graduating from the People’s Education Society Institute of Technology in Bangalore, India, while working on a Java mobile startup and training students on Java ME. United Nations High Commissioner for Refugees The United Nations High Commissioner for Refugees (UNHCR) is on the front lines of crises around the world, from civil wars to natural disasters. To help facilitate its mission of humanitarian relief, the UNHCR has developed a light-client Java application on the NetBeans platform. The Level One registration tool enables the UNHCR to collect information on the number of refugees and their water, food, housing, health, and other needs in the field, and combines that with geocoding information from various sources. This enables the UNHCR to deliver the appropriate kind and amount of assistance where it is needed. You can read more about the winners in the current issue of Java Magazine.

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• How can I thoroughly evaluate a prospective employer?

  - by glenviewjeff

  We hear much about code smells, test smells, and even project smells, but I have heard no discussion about employer "smells" outside of the Joel Test. After much frustration working for employers with a bouquet of unpleasant corporate-culture odors, I believe it's time for me to actively seek a more mature development environment. I've started assembling a list of questions to help vet employers by identifying issues during a job interview, and am looking for additional ideas. I suppose this list could easily be modified by an employer to vet an employee as well, but please answer from the interviewee's perspective. I think it would be important to ask many of these questions of multiple people to find out if consistent answers are given. For the most part, I tried to put the questions in each section in the order they could be asked. An undesired answer to an early question will often make follow-ups moot. Values What constitutes "well-written" software? What attributes does a good developer have? Same question for manager. Process Do you have a development process? How rigorously do you follow it? How do you decide how much process to apply to each project? Describe a typical project lifecycle. Ask the following if they don't come up otherwise: Waterfall/iterative: How much time is spent in upfront requirements gathering? upfront design? Testing Who develops tests (developers or separate test engineers?) When are they developed? When are the tests executed? How long do they take to execute? What makes a good test? How do you know you've tested enough? What percentage of code is tested? Review What is the review process like? What percentage of code is reviewed? Design? How frequently can I expect to participate as code/design reviewer/reviewee? What are the criteria applied to review and where do the criteria come from? Improvement What new tools and techniques have you evaluated or deployed in the past year? What training courses have your employees been given in the past year? What will I be doing for the first six months in your company (hinting at what kind of organized mentorship/training has been thought through, if any) What changes to your development process have been made in the past year? How do you improve and learn from your mistakes as an organization? What was your organizations biggest mistake in the past year, and how was it addressed? What feedback have you given to management lately? Was it implemented? If not, why? How does your company use "best practices?" How do you seek them out from the outside or within, and how do you share them with each other? Ethics Tell me about an ethical problem you or your employees experienced recently and how was it resolved? Do you use open-source software? What open-source contributions have you made? Follow-Ups I liked what @jim-leonardo said on this Stack Overflow question: Really a thing to ask yourself: "Does this person seem like they are trying to recruit me and make me interested?" I think this is one of the most important bits. If they seem to be taking the attitude that the only one being interviewed is you, then they probably will treat you poorly. Good interviewers understand they have to sell the position as much as the candidate needs to sell themselves. @SethP added: Glassdoor.com is a good web site for researching potential employers. It contains information about how specific companies conduct interviews...

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• When to use Aspect Oriented Architecture (AOA/AOD)

  When is it appropriate to use aspect oriented architecture? I think the only honest answer to this question is that it depends on the context for which the question is being asked. There really are no hard and fast rules regarding the selection of an architectural model(s) for a project because each model provides good and bad benefits. Every system is built with a unique requirements and constraints. This context will dictate when to use one type of architecture over another or in conjunction with others. To me aspect oriented architecture models should be a sub-phase in the architectural modeling and design process especially when creating enterprise level models. Personally, I like to use this approach to create a base architectural model that is defined by non-functional requirements and system quality attributes.   This general model can then be used as a starting point for additional models because it is targets all of the business key quality attributes required by the system.Aspect oriented architecture is a method for modeling non-functional requirements and quality attributes of a system known as aspects. These models do not deal directly with specific functionality. They do categorize functionality of the system. This approach allows a system to be created with a strong emphasis on separating system concerns into individual components. These cross cutting components enables a systems to create with compartmentalization in regards to non-functional requirements or quality attributes.  This allows for the reduction in code because an each component maintains an aspect of a system that can be called by other aspects. This approach also allows for a much cleaner and smaller code base during the implementation and support of a system. Additionally, enabling developers to develop systems based on aspect-oriented design projects will be completed faster and will be more reliable because existing components can be shared across a system; thus, the time needed to create and test the functionality is reduced.   Example of an effective use of Aspect Oriented ArchitectureIn my experiences, aspect oriented architecture can be very effective with large or more complex systems. Typically, these types of systems have a large number of concerns so the act of defining them is very beneficial for reducing the system’s complexity because components can be developed to address each concern while exposing functionality to the other system components. The benefits to using the aspect oriented approach as the starting point for a system is that it promotes communication between IT and the business due to the fact that the aspect oriented models are quality attributes focused so not much technical understanding is needed to understand the model.An example of this can be in developing a new intranet website. Common Intranet Concerns: Error Handling Security Logging Notifications Database connectivity Example of a not as effective use of Aspect Oriented ArchitectureAgain in my experiences, aspect oriented architecture is not as effective with small or less complex systems in comparison.  There is no need to model concerns for a system that has a limited amount of them because the added overhead would not be justified for the actual benefits of creating the aspect oriented architecture model.  Furthermore, these types of projects typically have a reduced time schedule and a limited budget.  The creation of the Aspect oriented models would increase the overhead of a project and thus increase the time needed to implement the system. An example of this is seen by creating a small application to poll a network share for new files and then FTP them to a new location.  The two primary concerns for this project is to monitor a network drive and FTP files to a new location.  There is no need to create an aspect model for this system because there will never be a need to share functionality amongst either of these concerns.  To add to my point, this system is so small that it could be created with just a few classes so the added layer of componentizing the concerns would be complete overkill for this situation. References:Brichau, Johan; D'Hondt, Theo. (2006) Aspect-Oriented Software Development (AOSD) - An Introduction. Retreived from: http://www.info.ucl.ac.be/~jbrichau/courses/introductionToAOSD.pdf

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• The theory of evolution applied to software

  - by Michel Grootjans

  I recently realized the many parallels you can draw between the theory of evolution and evolving software. Evolution is not the proverbial million monkeys typing on a million typewriters, where one of them comes up with the complete works of Shakespeare. We would have noticed by now, since the proverbial monkeys are now blogging on the Internet ;-) One of the main ideas of the theory of evolution is the balance between random mutations and natural selection. Random mutations happen all the time: millions of mutations over millions of years. Most of them are totally useless. Some of them are beneficial to the evolved species. Natural selection favors the beneficially mutated species. Less beneficial mutations die off. The mutated rabbit doesn't have to be faster than the fox. It just has to be faster than the other rabbits.   Theory of evolution Evolving software Random mutations happen all the time. Most of these mutations are so bad, the new species dies off, or cannot reproduce. Developers write new code all the time. New ideas come up during the act of writing software. The really bad ones don't get past the stage of idea. The bad ones don't get committed to source control. Natural selection favors the beneficial mutated species Good ideas and new code gets discussed in group during informal peer review. Less than good code gets refactored. Enhanced code makes it more readable, maintainable... A good set of traits makes the species superior to others. It becomes widespread A good design tends to make it easier to add new features, easier to understand the current implementations, easier to optimize for performance...thus superior. The best designs get carried over from project to project. They appear in blogs, articles and books about principles, patterns and practices.   Of course the act of writing software is deliberate. This can hardly be called random mutations. Though it sometimes might seem that code evolves through a will of its own ;-) Does this mean that evolving software (evolution) is better than a big design up front (creationism)? Not necessarily. It's a false idea to think that a project starts from scratch and everything evolves from there. Everyone carries his experience of what works and what doesn't. Up front design is necessary, but is best kept simple and minimal, just enough to get you started. Let the good experiences and ideas help to drive the process, whether they come from you or from others, from past experience or from the most junior developer on your team. Once again, balance is the keyword. Balance design up front with evolution on a daily basis. How do you know what balance is right? Through your own experience of what worked and what didn't (here's evolution again). Notes: The evolution of software can quickly degenerate without discipline. TDD is a discipline that leaves little to chance on that part. Write your test to describe the new behavior. Write just enough code to make it behave as specified. Refactor to evolve the code to a higher standard. The responsibility of good design rests continuously on each developers' shoulders. Promiscuous pair programming helps quickly spreading the design to the whole team.

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• JFall 2012

  - by Geertjan

  JFall 2012 was over far too soon! Seven tracks going on simultaneously in a great location, with many artifacts reminding me of JavaOne, and nice snacks and drinks afterwards. The day started, as such things always do, with a keynote. Thanks to @royvanrijn for the photo below, I didn't take any myself and without a picture this report might have been too dry: What you see above is Steve Chin riding into the keynote hall on his NightHacking bike. The keynote was interesting, I can't be too complimentary about it, since I was part of it myself. Bert Ertman introduced the day and then Steve Chin took over, together with Sharat Chander, Tom Eugelink, Timon Veenstra, and myself. We had a strict choreography for the keynote, one that would ensure a lot of variation and some unexpected surprises, such as Steve being thrown off the stage a few times by Bert because of mentioning JavaOne too many times, rather than the clearly much cooler JFall. Steve talked about JavaOne and the direction Java is headed in, Sharat talked about JavaME and embedded devices, Steve and Tom did a demo involving JavaFX, I did a Project Easel demo, and Timon from Ordina talked about his Duke's Choice Award winning AgroSense project. I think the Project Easel demo (which I repeated later in a screencast for Parleys arranged by Eugene Boogaart) came across well and several people I spoke to especially like the roundtrip/bi-directional work that can be done, from browser to IDE and back again, very simply and intuitively. (In a long conversation on the drive back home afterwards, the scenario of a designer laying out the UI in HTML and then handing the HTML to a developer for back-end work, a developer who would then find it convenient to open the HTML in a browser and quickly navigate from the browser to the resources within the IDE, was discussed and considered to be extremely interesting and worth considering adopting NetBeans for, for no other reason than that.) Later I attended a session by David Delabassee on Java EE 7, Hans Dockter on Gradle, and Sander Mak on cross-build injection attacks. I was sorry to have missed Martijn Verburg's session, which sounded like it was really fantastic, among others, such as Gerrit Grunwald. I did a session too, entitled "Unlocking the Java EE 6 Platform", which was very well attended, pretty much a full room, and the demo went very smoothly. I talked to many people, e.g., a long time with Hans Dockter about how cool Gradle is and how great the Gradle/NetBeans plugin is turning out to be. I also had a long conversation (and did a demo) with Chris Chedgey, from Structure101, after his session, which was incredibly well attended; very interesting how popular modularity is. I met several people for the first time, as well as some colleagues from past places I've worked at. All in all, it was a great conference, unfortunately too short, which was very well attended (clearly over 1000) people, with several international speakers, as well as international attendees such as Mattias Karlsson, Sweden JUG leader. And, unsurprisingly, I came across NetBeans Platform applications again, none of which I had ever heard of before. In each case, "our fat client application" was mentioned in passing, never as a main application, and never in a context where there are plans for the application to be migrated to the web or mobile, simply because doing so makes no business sense at all. Great times at JFall, looking forward to meeting with some of the people I met again soon.

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• My First Iteration Zero

  - by onefloridacoder

  I recently watched a web cast that covered the idea of planning from the concept stage to the product backlog.  It was the first content I had seen related to Iteration Zero and it made a lot of sense from a planning and engagement perspective where the customer is concerned.  It illuminated some of the problems I’ve experienced with getting a large project of the ground.  The idea behind this is to just figure out get everyone to understand what needs to be constructed and to build the initial feature set from a *very* high level.  Once that happens other parts of the high level construction start to take place.  You end up with a feature list that describes what the business wants the system to do, and what it potentially may (or may not) interact with.  Low tech tools are used to create UI mockups that can be used as a starting point for some of the key UI pieces. Toward the end of the webcast they speaker introduced something that was new to me.  He referred to it as an executable skeleton or the steel thread.  The idea with this part of the webcast was to describe walking through the different mocked layers of the application.  Not all layers and collaborators are involved at this stage since it’s Iteration Zero, and each layer is either hard-coded or completely mocked to provide a 35K foot view of how the different layers layers work together.  So imagine two actors on each side of a layer diagram and the flow goes down from the upper left side down through a a consumer, thorough a service layer and then back up the service layer to the destination/actor. I would imagine much could be discussed moving through new/planned or existing/legacy layers, or a little of both to see what’s implied by the current high-level design. One part of the web cast has the business and design team creating the product box (think of your favorite cereal or toy box) with all of the features and even pictures laid out on the outside of the box.  The notion here is that if you handed this box to someone and told them your system was inside they would have an understanding of what the system would be able to do, or the features it could provide.    One of the interesting parts of the webcast was where the speaker described that he worked with a couple of groups in the same room and each group came up with a different product box – the point is that each group had a different idea of what the system was supposed to do.  At this point of the project I thought that to be valuable considering my experience has been that historically this has taken longer than a week to realize that the business unit and design teams see the high level solution differently.  Once my box is finished I plan on moving to the next stage of solution definition which is to plan the UI for this small application using Excel, to map out the UI elements.  I’m my own customer so it feels like cheating, but taking these slow deliberate steps have already provided a few learning opportunities.    So I resist the urge to load all of my user stories into my newly installed VS2010  TFS project and try to reduce or add to, the number of user stories and/or refine the high level estimates I’ve come up with so far.

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• Create a Remote Git Repository from an Existing XCode Repository

  - by codeWithoutFear

  Introduction Distributed version control systems (VCS’s), like Git, provide a rich set of features for managing source code.  Many development tools, including XCode, provide built-in support for various VCS’s.  These tools provide simple configuration with limited customization to get you up and running quickly while still providing the safety net of basic version control. I hate losing (and re-doing) work.  I have OCD when it comes to saving and versioning source code.  Save early, save often, and commit to the VCS often.  I also hate merging code.  Smaller and more frequent commits enable me to minimize merge time and effort as well. The work flow I prefer even for personal exploratory projects is: Make small local changes to the codebase to create an incrementally improved (and working) system. Commit these changes to the local repository.  Local repositories are quick to access, function even while offline, and provides the confidence to continue making bold changes to the system.  After all, I can easily recover to a recent working state. Repeat 1 & 2 until the codebase contains “significant” functionality and I have connectivity to the remote repository. Push the accumulated changes to the remote repository.  The smaller the change set, the less likely extensive merging will be required.  Smaller is better, IMHO. The remote repository typically has a greater degree of fault tolerance and active management dedicated to it.  This can be as simple as a network share that is backed up nightly or as complex as dedicated hardware with specialized server-side processing and significant administrative monitoring. XCode’s out-of-the-box Git integration enables steps 1 and 2 above.  Time Machine backups of the local repository add an additional degree of fault tolerance, but do not support collaboration or take advantage of managed infrastructure such as on-premises or cloud-based storage. Creating a Remote Repository These are the steps I use to enable the full workflow identified above.  For simplicity the “remote” repository is created on the local file system.  This location could easily be on a mounted network volume. Create a Test Project My project is called HelloGit and is located at /Users/Don/Dev/HelloGit.  Be sure to commit all outstanding changes.  XCode always leaves a single changed file for me after the project is created and the initial commit is submitted. Clone the Local Repository We want to clone the XCode-created Git repository to the location where the remote repository will reside.  In this case it will be /Users/Don/Dev/RemoteHelloGit. Open the Terminal application. Clone the local repository to the remote repository location: git clone /Users/Don/Dev/HelloGit /Users/Don/Dev/RemoteHelloGit Convert the Remote Repository to a Bare Repository The remote repository only needs to contain the Git database.  It does not need a checked out branch or local files. Go to the remote repository folder: cd /Users/Don/Dev/RemoteHelloGit Indicate the repository is “bare”: git config --bool core.bare true Remove files, leaving the .git folder: rm -R * Remove the “origin” remote: git remote rm origin Configure the Local Repository The local repository should reference the remote repository.  The remote name “origin” is used by convention to indicate the originating repository.  This is set automatically when a repository is cloned.  We will use the “origin” name here to reflect that relationship. Go to the local repository folder: cd /Users/Don/Dev/HelloGit Add the remote: git remote add origin /Users/Don/Dev/RemoteHelloGit Test Connectivity Any changes made to the local Git repository can be pushed to the remote repository subject to the merging rules Git enforces. Create a new local file: date > date.txt /li> Add the new file to the local index: git add date.txt Commit the change to the local repository: git commit -m "New file: date.txt" Push the change to the remote repository: git push origin master Now you can save, commit, and push/pull to your OCD hearts’ content! Code without fear! --Don

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• Impressions of Pivotal Tracker

  Pivotal Tracker is a free, online agile project management system. Ive been using it recently to better communicate to customers about the current state of our project. In Pivotal Tracker, the unit of work is a story and stories are arranged into iterations or delivery cycles. Stories can be any level of granularity you want, but the idea is to use stories to communicate clearly to customers, so you dont want to write a novel. You especially dont want to write a list of detailed programming tasks. A good story for a point of sale system might be: Allow managers to override the price of an item while ringing up a customer. A less useful story: Script out the process of adding a manager flag to the user table and stage that script into the deploy directory. Stories are estimated using a point scale, by default 1, 2 or 3. Iterations are then automatically laid out by combining enough tasks to fill the point total for that period of time. You have to start with a guess on how many points your team can do in an iteration, then adjust with real data as you complete iterations. This is basic agile methodology, but where Pivotal Tracker adds value is that it automatically and graphically lays out iterations for you on your project site. This makes communication and planning easy. Compiling release notes is no longer painful as it has been clear from the outset what work is going on. While I much prefer Pivotal Trackers customer facing interface over what we used previously (TFS), I see a couple of gaps. First, I have not able to make much headway with the reporting tools. Despite my complaints about TFS, it can produce some nice reports. Second, its not clear where if at all, Id keep track of purely internal tasks. Im talking about server maintenance, cleaning up source control, checking back on some code which you never quite felt right about. Theres no purpose in cluttering up an iteration backlog with these items, but if you dont track them, you lose them. Im not sure what a good answer for that is. One gap I thought Id see, which I dont, is more granular dev tasks. If Im implementing a story, Ill write out the steps and track my progress, but really, those steps arent useful to anybody but me. The only time Ive found that level of detail really useful is when my tasks are defined at too high a level anyway or when Im working with someone who needs more coaching and might not be able to finish a story in time without some scaffolding to get them going. You can learn more about Pivotal Tracker at: http://www.pivotaltracker.com/learnmore.   --- Relevant Links --- A good intro to stories: http://www.agilemodeling.com/artifacts/userStory.htmDid you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• Valuing "Working Software over Comprehensive Documentation"

  - by tom.spitz

  Normal 0 false false false EN-US X-NONE 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:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} I subscribe to the tenets put forth in the Manifesto for Agile Software Development - http://agilemanifesto.org. As Oracle's chief methodologist, that might seem a self-deprecating attitude. After all, the agile manifesto tells us that we should value "individuals and interactions" over "processes and tools." My job includes process development. I also subscribe to ideas put forth in a number of subsequent works including Balancing Agility and Discipline: A Guide for the Perplexed (Boehm/Turner, Addison-Wesley) and Agile Project Management: Creating Innovative Products (Highsmith, Addison-Wesley). Both of these books talk about finding the right balance between "agility and discipline" or between a "predictive and adaptive" project approach. So there still seems to be a place for us in creating the Oracle Unified Method (OUM) to become the "single method framework that supports the successful implementation of every Oracle product." After all, the real idea is to apply just enough ceremony and produce just enough documentation to suit the needs of the particular project that supports an enterprise in moving toward its desired future state. The thing I've been struggling with - and the thing I'd like to hear from you about right now - is the prevalence of an ongoing obsession with "documents." OUM provides a comprehensive set of guidance for an iterative and incremental approach to engineering and implementing software systems. Our intent is first to support the information technology system implementation and, as necessary, support the creation of documentation. OUM, therefore, includes a supporting set of document templates. Our guidance is to employ those templates, sparingly, as needed; not create piles of documentation that you're not gonna (sic) need. In other words, don't serve the method, make the method serve you. Yet, there seems to be a "gimme" mentality in some circles that if you give me a sample document - or better yet - a repository of samples - then I will be able to do anything cheaply and quickly. The notion is certainly appealing AND reuse can save time. Plus, documents are a lowest common denominator way of packaging reusable stuff. However, without sustained investment and management I've seen "reuse repositories" turn quickly into garbage heaps. So, I remain a skeptic. I agree that providing document examples that promote consistency is helpful. However, there may be too much emphasis on the documents themselves and not enough on creating a system that meets the evolving needs of the business. How can we shift the emphasis toward working software and away from our dependency on documents - especially on large, complex implementation projects - while still supporting the need for documentation? I'd like to hear your thoughts.

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• Disneyland Inside Out on iPhone and Android

  - by Ryan Cain

  It's hard to believe October was the last time I was over here on my blog.  Ironically after getter the developer phone from Microsoft I have been knee deep in iPhone programming and for the past few weeks Android programming again.  This time I've spent all my non-working hours programming a fun project for my "other" website, Disneyland Inside Out.  Disneyland Inside Out, a vacation planning site for Disneyland in California, has been around in various forms since June 1996.  It has always been a place for me to explore new technologies and learn about some of the new trends on the web.  I recently migrated the site over to DotNetNuke and have been building out custom modules for DNN.  I've also been hacking things together w/ the URLRewrite module in IIS 7.5 to provide strong SEO optimized URLs.  I can't say all that has really stuck within the DNN model of doing things, but it has worked pretty well. As part of my learning process, I spent most of the Fall bringing Disneyland Inside Out to the iPhone.  I will post more details on my development experiences later.  But this project gave me a really great opportunity to get a good feel for Objective-C development.  After 3 months I actually feel somewhat competent in the language and iPhone SDK, instead of just floundering around getting things to work.  The project also gave me a chance to play with some new frameworks on the iPhone and really dig into the Facebook SDK.  I also dug into some of the Gowalla REST api's as well.  We've been live with the app in iTunes for just about 10 days now, and have been sitting in the top 200 of free travel apps for the past few days.  You can get more info and the direct iTunes download link on our site: Disneyland Inside Out for iPhone Since launching the iPhone version I have gotten back into Android development, porting the Disneyland Inside Out app over to Android.  As I said in my first review of iPhone vs. Android, coming from a managed code background, Android is much easier to get going with.  I just about 3 weeks total I will have about 85 - 90% of the functionality up and running in the Android app, that took probably 1.5 - 2x's that time for iPhone.  That isn't a totally fair comparison as I am much more comfortable w/ Xcode and Objective-C today and can get some of the basic stuff done much faster than I could in the fall.  Though I'd say some of the hardest code to debug is still the null pointer issues on objects that were dealloc'd too early in Objective-C.  This isn't too bad with the NSZoombies enabled for synchronous code, but when you have a lot of async, which my app does, it can be hairy at times to track exactly what was causing the issue.   I will post more details later, as I am trying to wrap up a beta of the Android app today.  But in the meantime, if you have an iPhone, iPod Touch or iPad head on over to the site and take a look at my app.

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• Doubts about several best practices for rest api + service layer

  - by TheBeefMightBeTough

  I'm going to be starting a project soon that exposes a restful api for business intelligence. It may not be limited to a restful api, so I plan to delegate requests to a service layer that then coordinates multiple domain objects (each of which have business logic local to the object). The api will likely have many calls as it is a long-term project. While thinking about the design, I recalled a few best practices. 1) Use command objects at the controller layer (I'm using Spring MVC). 2) Use DTOs at the service layer. 3) Validate in both the controller and service layer, though for different reasons. I have my doubts about these recommendations. 1) Using command objects adds a lot of extra single-purpose classes (potentially one per request). What exactly is the benefit? Annotation based validation can be done using this approach, sure. What if I have two requests that take the same parameters, but have different validation requirements? I would have to have two different classes with exactly the same members but different annotations? Bleh. 2) I have heard that using DTOs is preferable to parameters because it makes for more maintainable code down the road (say, e.g., requirements change and the service parameters need to be altered). I don't quite understand this. Shouldn't an api be more-or-less set in stone? I would understand that in the early phases of a project (or, especially, an entire company) the domain itself will not be well understood, and thus core domain objects may change along with the apis that manipulate these objects. At this point however the number of api methods should be small and their dependents few, so changes to the methods could easily be tolerated from a maintainability standpoint. In a large api with many methods and a substantial domain model, I would think having a DTO for potentially each domain object would become unwieldy. Am I misunderstanding something here? 3) I see validation in the controller and service layer as redundant in most cases. Why would I validate that parameters are not null and are in general well formed in the controller if the service is going to do exactly the same (and more). Couldn't I just do all the validation in the service and throw a runtime exception with a list of bad parameters then catch that in the controller to make the error messages more presentable? Better yet, couldn't I just make the error messages user-friendly in the service and let the exception trickle up to a global handler (ControllerAdvice in spring, for example)? Is there something wrong with either of these approaches? (I do see a use case for controller validation if the input does not map one-to-one with the service input, but since the controllers are for a rest api and not forms, the api parameters will probably map directly to service parameters.) I do also have a question about unchecked vs checked exceptions. Namely, I'm not really sure why I'd ever want to use a checked exception. Every time I have seen them used they just get wrapped into general exceptions (DomainException, SystemException, ApplicationException, w/e) to reduce the signature length of methods, or devs catch Exception rather than dealing with the App1Exception, App2Exception, Sys1Exception, Sys2Exception. I don't see how either of these practices is very useful. Why not just use unchecked exceptions always and catch the ones you actually do care about? You could just document what unchecked exceptions the method throws.

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