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• Silverlight Cream for January 14, 2011 -- #1027

  - by Dave Campbell

  In this Issue: Sigurd Snørteland, Yochay Kiriaty, WindowsPhoneGeek(-2-), Jesse Liberty(-2-), Kunal Chowdhury, Martin Krüger(-2-), Jonathan Cardy. Above the Fold: Silverlight: "Image Viewer using a GridSplitter control" Martin Krüger WP7: "Implementing WP7 ToggleImageControl from the ground up: Part1" WindowsPhoneGeek VS2010 Templates: "MVVM Project Templates for Visual Studio 2010" Jonathan Cardy From SilverlightCream.com: BabySmash7 - a WP7 children's game (source code included) Sigurd Snørteland not only brings Scott Hanselman's Baby Smash to WP7, but he's delivering the source to us as well as discussion of the app. Windows Push Notification Server Side Helper Library Yochay Kiriaty has a tutorial up on Push Notification... not explaining them, but a discussion of a WP7 Push Recipe that provides an easy way for sending all 3 kinds of push notification messages currently supported. Implementing WP7 ToggleImageControl from the ground up: Part1 WindowsPhoneGeek has a great 2-part series up on building a useful WP7 custom control -- a ToggleImage control... this part 1 is definition, deciding on Visual states, etc... buckle up... this is good stuff Implementing WP7 ToggleImageControl from the ground up: Part2 Part 2 in WindowsPhoneGeek's series is also up and where the real fun lives -- implementing the behavior of the control... and the source is available at the end of this post. The Full Stack #5 – Entity Framework Code First Jesse Liberty has episode 5 of the "Full Stack" series he and Jon Galloway are doing and are discussing Entity Framework Code First. Windows Phone From Scratch #18 – MVVM Light Toolkit Soup To Nuts 3 Jesse Liberty also has part 3 of his MVVMLight and WP7 post up and is digging into messaging in this one... for example view <--> ViewModel communication. Exploring Ribbon Control for Silverlight (Part - 1) Kunal Chowdhury has part 1 of a series up on using the Silverlight Ribbon Control from DevComponents... lots of information and a great intro to a great control. Image Viewer using a GridSplitter control Martin Krüger has a very nice picture viewer up as a demo and code available that simply uses the GridSplitter to implement tha aperture... check it out. How to: Gentle animation of a magnify effect Martin Krüger's latest is a take-off on a prior post he links to called 'just for fun' in which he smoothly animates a magnify effect... just very cool animation... explanation and source. MVVM Project Templates for Visual Studio 2010 Jonathan Cardy has a couple resources you probably wanna grab... two MVVM project templates for VS2010... one WPF and one Silverlight 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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• Keep Track of Your Tasks with toDoo

  - by Asian Angel

  A tasks list can be convenient but most times you can not include details for those tasks or have to have an online account to do so. If you want to keep your tasks list with you on your computer or laptop and be able to add plenty of details then you might want to look at toDoo. Note: Requires Adobe AIR (download link at bottom of article). toDoo in Action Once you have installed toDoo everything is rather straightforward for getting started. The first time that you start toDoo there will be a temporary “fill-in” for the “Subject & Details Areas”. Simply highlight over the temporary text and add your information. Notice that if desired you can easily set a custom date and time for your tasks right below the “Details Area”. Note: toDoo does not minimize to the “System Tray”. Once you have everything set all that you need to do is click on “add task”. Here was our first new task being viewed in the “toDoo Description Tab”. Time to add a second task…here you can see the drop-down calendar. You can scroll through and select a different month very easily…just click on the desired day and it will be automatically set. Adding our second task… If you need to edit any of the details for a particular task you can do so in the “Edit toDoo Tab”. This nice little app is convenient and easy to use. Conclusion ToDoo is a simple straightforward app that lets you keep track of your tasks list and relevant details without an online account (especially helpful if you are without a wireless connection at a given moment). If you are looking for more of a list approach that runs on your desktop, then check out our article on Doomi here. Links Download ToDoo at Softpedia Download ToDoo at Adobe Marketplace Download Adobe AIR Similar Articles Productive Geek Tips Turn Chrome’s New Tab Page into a Google Tasks PageMake To-Do Bar in Outlook 2007 Show Only Today’s TasksAdd a non-Google Tasks List to ChromeKeep Track of Homework Assignments with SoshikuTrack the Amount of Time You Spend Online in Firefox TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Download Videos from Hulu Pixels invade Manhattan Convert PDF files to ePub to read on your iPad Hide Your Confidential Files Inside Images Get Wildlife Photography Tips at BBC’s PhotoMasterClasses Mashpedia is a Real-time Encyclopedia

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• Messaging Systems – Handshaking, Reconciliation and Tracking for Data Transparency

  - by Ahsan Alam

  As many corporations build business partnerships with other organizations, the need to share information becomes necessary. Large amount of data sharing using snail mail, email and/or fax are quickly becoming a thing of the past. More and more organizations are relying heavily on Ftp and/or Web Service to exchange data. Corporations apply wide range of technologies and techniques based on available resources and data transfer needs. Sometimes, it involves simple home-grown applications. Other times, large investments are made on products like BizTalk, TIBCO etc. Complexity of information management also varies significantly from one organizations to another. Some may deal with handful of simple steps to process and manage shared data; whereas others may rely on fairly complex processes with heavy interaction with internal and external systems in order to serve the business needs. It is not surprising that many of these systems end up becoming black boxes over a period of time. Consequently, people and business start to rely more and more on developers and support personnel just to extract simple information adding to the loss of productivity. One of the most important factor in any business is transparency to data irrespective of technology preferences and the complexity of business processes. Not knowing the state of data could become very costly to the business. Being involved in messaging systems for some time now, I have heard the same type of questions over and over again. Did we transmit messages successfully? Did we get responses back? What is the expected turn-around-time? Did the system experience any errors? When one company transmits data to one or more company, it may invoke a set of processes that could complete in matter of seconds, or it could days. As data travels from one organizations to another, the uncertainty grows, and the longer it takes to track uncertain state of the data the costlier it gets for the business, So, in every business scenario, it's extremely important to be aware of the state of the data.   Architects of messaging systems can take several steps to aid with data transparency. Some forms of data handshaking and reconciliation mechanism as well as extensive data tracking can be incorporated into the system to provide clear visibility to the data. What do I mean by handshaking and reconciliation? Some might consider these to be a single concept; however, I like to consider them in two unique categories. Handshaking serves as message receipts or acknowledgment. When one transmits messages to another, the receiver must acknowledge each message by sending immediate responses for each transaction. Whenever we use Web Services, handshaking is often achieved utilizing request/reply pattern. Similarly, if Ftp is used, a receiver can acknowledge by dropping messages for the sender as soon as the files are picked up. These forms of handshaking or acknowledgment informs the message sender and receiver that a successful transaction has occurred. I have mentioned earlier that it could take anywhere from a few seconds to a number of days before shared data is completely processed. In addition, whenever a batched transaction is used, processing time for each data element inside the batch could also vary significantly. So, in order to successfully manage data processing, reconciliation becomes extremely important; otherwise it may result into data loss or in some cases hefty penalty. Reconciliation can be done in many ways. Partner organizations can share and compare ad hoc reports to achieve reconciliation. On the other hand, partners can agree on some type of systematic reconciliation messages. Systems within responsible parties can trigger messages to partners as soon as the data process completes.   Next step in the data transparency is extensive data tracking. Some products such as BizTalk and TIBCO provide built-in functionality for data tracking; however, built-in functionality may not always be adequate. Sometimes additional tracking system (or databases) needs to be built in order monitor all types of data flow including, message transactions, handshaking, reconciliation, system errors and many more. If these types of data are captured, then these can be presented to business users in any forms or fashion. When business users are empowered with such information, then the reliance on developers and support teams decreases dramatically.   In today's collaborative world of information sharing, data transparency is key to the success of every business. The state of business data will constantly change. However, when people have easier access to various states of data, it allows them to make better and quicker decisions. Therefore, I feel that data handshaking, reconciliation and tracking is very important aspect of messaging systems.

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• Sending Parameters with the BizTalk HTTP Adapter

  - by Christopher House

  I've never had occaison to use the BizTalk HTTP adapter since I've always needed SOAP rather than just POX (plain old XML).  Yesterday we decided that we're going to expose some data via a Java servlet that will accept an HTTP post and respond with POX.  I knew BizTalk had an HTTP adapter but I had no idea what it's capabilities were. After a quick read through the BizTalk docs, it was apparent that the HTTP send adapter does in fact do posts.  The concern I had though was how we were going to supply parameters to the servlet.  The examples I had seen using the HTTP adapter all involved posting an XML message to some HTTP location.  Our Java guy, however didn't want to take that approach.  He wanted us to provide a query string via post, much like you'd expect to see on an HTTP get.  I decided to put together a little test scenario and see what I could come up with.  We didn't have a test servlet I could go against and my Java experience is virtually nill, so I decided to put together an ASP.Net project to act as the servlet.  It didn't need to be fancy, just one HttpHandler that accepts a post, reads a parameter and returns XML.  With the HttpHandler done, I put together a simple orchestration to send a message to the handler.  I started by having the orch send a message of type System.String to see what it would look like when the handler received it. I set a breakpoint in my handler and kicked off the orchestration.  Below is what I saw: As I suspected, because of BizTalk's XML serialization, System.String was not going to work.  I thought back to my BizTalk 2004 days and I project I worked on that required sending HTML formatted emails via the SMTP adapter.  To acomplish that, I had used a .Net class with a custom serialization formatter that I got from a Microsoft sample.  The code for the class, RawString can be found here. I created a new class library with the RawString class as well as a static factory class, referenced that in my orchestration project and changed my message type from System.String to RawString.  Below is what the code in my message construction looks like: After deploying the updated orchestration, I fired it off again and checked the breakpoint in my HttpHandler.  This is what I saw: And there you have it.  The RawString message type allowed me to pass a query string in the HTTP post without wrapping it in XML.

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• Skechers Leverages Oracle Applications, Business Intelligence and On Demand Offerings to Drive Long-Term Growth

  - by user801960

  This month Oracle Retail in the USA announced that Skechers - a world leading lifestyle footwear retailer - would be adopting several Oracle Retail products as part of their global growth strategy and to maximise business efficiency.  While based primarily in the USA, Skechers is a respected retailer across the world and has been an Oracle customer since 1997.  The key information about the announcement is below.  To find out more about Skechers visit their website: http://www.skechers.com/  Skechers U.S.A. Inc., an award-winning global leader in the lifestyle footwear industry, has upgraded and expanded its Oracle® Applications investment, implemented Oracle Database and moved to Oracle On Demand, Oracle’s premier cloud service to support rapid growth across its retail and wholesale channels. The new business information systems are part of a larger initiative for the billion-dollar-plus footwear company to fuel growth, reduce total cost of ownership and enable the business to respond faster to market opportunities. With more than 3,000 styles of shoes to design, develop and market, Skechers upgraded to Oracle’s PeopleSoft Enterprise Financial Management and PeopleSoft Supply Chain Management to increase operational efficiencies and improve controls by establishing an integrated, industry-specific platform. An Oracle customer since 1997, Skechers implemented PeopleSoft Enterprise Real Estate Management to meet the rapid growth of its retail stores worldwide. The company is the first customer to go live on the Real Estate Management module and worked closely with Oracle to provide development insight. Skechers also implemented Oracle Fusion Governance, Risk, and Compliance applications. This deployment enabled the company to leverage its existing corporate governance and compliance efforts throughout the global enterprise and more effectively manage the audit processes across multiple business units, processes and systems while reducing audit costs. Next, Skechers leveraged Oracle Financial Analytics, a pre-built Oracle Business Intelligence Application and PeopleSoft Enterprise Project Costing and PeopleSoft Enterprise Contracts to develop a custom Royalty Management dashboard, providing managers with better financial visibility to the company’s licensing contracts. The company switched to Oracle Database and moved database hosting and management to Oracle On Demand to reduce maintenance, implementation and system administration costs. As a result, Skechers is also achieving a better response time and is delivering a higher level of 24x7 support. OSI Consulting, a Platinum partner in Oracle PartnerNetwork (OPN), provided implementation and integration services to Skechers.   To view the full announcement please click here

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• Subterranean IL: Filter exception handlers

  - by Simon Cooper

  Filter handlers are the second type of exception handler that aren't accessible from C#. Unlike the other handler types, which have defined conditions for when the handlers execute, filter lets you use custom logic to determine whether the handler should be run. However, similar to a catch block, the filter block does not get run if control flow exits the block without throwing an exception. Introducing filter blocks An example of a filter block in IL is the following: .try { // try block } filter { // filter block endfilter }{ // filter handler } or, in v1 syntax, TryStart: // try block TryEnd: FilterStart: // filter block HandlerStart: // filter handler HandlerEnd: .try TryStart to TryEnd filter FilterStart handler HandlerStart to HandlerEnd In the v1 syntax there is no end label specified for the filter block. This is because the filter block must come immediately before the filter handler; the end of the filter block is the start of the filter handler. The filter block indicates to the CLR whether the filter handler should be executed using a boolean value on the stack when the endfilter instruction is run; true/non-zero if it is to be executed, false/zero if it isn't. At the start of the filter block, and the corresponding filter handler, a reference to the exception thrown is pushed onto the stack as a raw object (you have to manually cast to System.Exception). The allowed IL inside a filter block is tightly controlled; you aren't allowed branches outside the block, rethrow instructions, and other exception handling clauses. You can, however, use call and callvirt instructions to call other methods. Filter block logic To demonstrate filter block logic, in this example I'm filtering on whether there's a particular key in the Data dictionary of the thrown exception: .try { // try block } filter { // Filter starts with exception object on stack // C# code: ((Exception)e).Data.Contains("MyExceptionDataKey") // only execute handler if Contains returns true castclass [mscorlib]System.Exception callvirt instance class [mscorlib]System.Collections.IDictionary [mscorlib]System.Exception::get_Data() ldstr "MyExceptionDataKey" callvirt instance bool [mscorlib]System.Collections.IDictionary::Contains(object) endfilter }{ // filter handler // Also starts off with exception object on stack callvirt instance string [mscorlib]System.Object::ToString() call void [mscorlib]System.Console::WriteLine(string) } Conclusion Filter exception handlers are another exception handler type that isn't accessible from C#, however, just like fault handlers, the behaviour can be replicated using a normal catch block: try { // try block } catch (Exception e) { if (!FilterLogic(e)) throw; // handler logic } So, it's not that great a loss, but it's still annoying that this functionality isn't directly accessible. Well, every feature starts off with minus 100 points, so it's understandable why something like this didn't make it into the C# compiler ahead of a different feature.

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• SQL SERVER – Fundamentals of Columnstore Index

  - by pinaldave

  There are two kind of storage in database. Row Store and Column Store. Row store does exactly as the name suggests – stores rows of data on a page – and column store stores all the data in a column on the same page. These columns are much easier to search – instead of a query searching all the data in an entire row whether the data is relevant or not, column store queries need only to search much lesser number of the columns. This means major increases in search speed and hard drive use. Additionally, the column store indexes are heavily compressed, which translates to even greater memory and faster searches. I am sure this looks very exciting and it does not mean that you convert every single index from row store to column store index. One has to understand the proper places where to use row store or column store indexes. Let us understand in this article what is the difference in Columnstore type of index. Column store indexes are run by Microsoft’s VertiPaq technology. However, all you really need to know is that this method of storing data is columns on a single page is much faster and more efficient. Creating a column store index is very easy, and you don’t have to learn new syntax to create them. You just need to specify the keyword “COLUMNSTORE” and enter the data as you normally would. Keep in mind that once you add a column store to a table, though, you cannot delete, insert or update the data – it is READ ONLY. However, since column store will be mainly used for data warehousing, this should not be a big problem. You can always use partitioning to avoid rebuilding the index. A columnstore index stores each column in a separate set of disk pages, rather than storing multiple rows per page as data traditionally has been stored. The difference between column store and row store approaches is illustrated below: In case of the row store indexes multiple pages will contain multiple rows of the columns spanning across multiple pages. In case of column store indexes multiple pages will contain multiple single columns. This will lead only the columns needed to solve a query will be fetched from disk. Additionally there is good chance that there will be redundant data in a single column which will further help to compress the data, this will have positive effect on buffer hit rate as most of the data will be in memory and due to same it will not need to be retrieved. Let us see small example of how columnstore index improves the performance of the query on a large table. As a first step let us create databaseset which is large enough to show performance impact of columnstore index. The time taken to create sample database may vary on different computer based on the resources. USE AdventureWorks GO -- Create New Table CREATE TABLE [dbo].[MySalesOrderDetail]( [SalesOrderID] [int] NOT NULL, [SalesOrderDetailID] [int] NOT NULL, [CarrierTrackingNumber] [nvarchar](25) NULL, [OrderQty] [smallint] NOT NULL, [ProductID] [int] NOT NULL, [SpecialOfferID] [int] NOT NULL, [UnitPrice] [money] NOT NULL, [UnitPriceDiscount] [money] NOT NULL, [LineTotal] [numeric](38, 6) NOT NULL, [rowguid] [uniqueidentifier] NOT NULL, [ModifiedDate] [datetime] NOT NULL ) ON [PRIMARY] GO -- Create clustered index CREATE CLUSTERED INDEX [CL_MySalesOrderDetail] ON [dbo].[MySalesOrderDetail] ( [SalesOrderDetailID]) GO -- Create Sample Data Table -- WARNING: This Query may run upto 2-10 minutes based on your systems resources INSERT INTO [dbo].[MySalesOrderDetail] SELECT S1.* FROM Sales.SalesOrderDetail S1 GO 100 Now let us do quick performance test. I have kept STATISTICS IO ON for measuring how much IO following queries take. In my test first I will run query which will use regular index. We will note the IO usage of the query. After that we will create columnstore index and will measure the IO of the same. -- Performance Test -- Comparing Regular Index with ColumnStore Index USE AdventureWorks GO SET STATISTICS IO ON GO -- Select Table with regular Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO -- Table 'MySalesOrderDetail'. Scan count 1, logical reads 342261, physical reads 0, read-ahead reads 0. -- Create ColumnStore Index CREATE NONCLUSTERED COLUMNSTORE INDEX [IX_MySalesOrderDetail_ColumnStore] ON [MySalesOrderDetail] (UnitPrice, OrderQty, ProductID) GO -- Select Table with Columnstore Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO It is very clear from the results that query is performance extremely fast after creating ColumnStore Index. The amount of the pages it has to read to run query is drastically reduced as the column which are needed in the query are stored in the same page and query does not have to go through every single page to read those columns. If we enable execution plan and compare we can see that column store index performance way better than regular index in this case. Let us clean up the database. -- Cleanup DROP INDEX [IX_MySalesOrderDetail_ColumnStore] ON [dbo].[MySalesOrderDetail] GO TRUNCATE TABLE dbo.MySalesOrderDetail GO DROP TABLE dbo.MySalesOrderDetail GO In future posts we will see cases where Columnstore index is not appropriate solution as well few other tricks and tips of the columnstore index. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Index, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• JavaScript Class Patterns

  - by Liam McLennan

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

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• JavaScript Class Patterns

  - by Liam McLennan

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

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• JavaFX 2.0 at Devoxx 2011

  - by Janice J. Heiss

  JavaFX Sessions Abound JavaFX had a big presence at Devoxx 2011 as witnessed by the number of sessions this year given by leading JavaFX movers and shakers.     “JavaFX 2.0 -- A Java Developer's Guide” by Java Champions Stephen Chin and Peter Pilgrim     “JavaFX 2.0 Hands On” by Jasper Potts and Richard Bair     “Animation Bringing your User Interfaces to Life” by Michael Heinrichs and John Yoong (JavaFX development team)     “Complete Guide to Writing Custom Bindings in JavaFX 2.0” by Michael Heinrichs (JavaFX development team)     “Java Rich Clients with JavaFX 2.0” by Jasper Potts and Richard Bair     “JavaFX Properties & Bindings for Experts” (and those who want to become experts) by Michael Heinrichs (JavaFX development team)     “JavaFX Under the Hood” by Richard Bair     “JavaFX Open Mic” with Jasper Potts and Richard Bair With the release of JavaFX 2.0 and Oracle’s move towards an open development model with an open bug database already created, it’s a great time for developers to take the JavaFX plunge. One Devoxx attendee, Mark Stephens, a developer at IDRsolutions blogged about a problem he was having setting up JavaFX on NetBeans to work on his Mac. He wrote: “I’ve tried desperate measures (I even read and reread the instructions) but it did not help. Luckily, I am at Devoxx at the moment and there seem to be a lot of JavaFX gurus here (and it is running on all their Macs). So I asked them… It turns out that sometimes the software does not automatically pickup the settings like it should do if you give it the JavaFX SDK path. The solution is actually really simple (isn’t it always once you know). Enter these values manually and it will work.” He simply entered certain values and his problem was solved. He thanked Java Champion Stephen Chin, “for a great talk at Devoxx and putting me out of my misery.” JavaFX in Java Magazine Over in the November/December 2011 issue of Java Magazine, Oracle’s Simon Ritter, well known for his creative Java inventions at JavaOne, has an article up titled “JavaFX and Swing Integration” in which he shows developers how to use the power of JavaFX to migrate Swing interfaces to JavaFX. The consensus among JavaFX experts is that JavaFX is the next step in the evolution of Java as a rich client platform. In the same issue Java Champion and JavaFX maven James Weaver has an article, “Using Transitions for Animation in JavaFX 2.0”. In addition, Oracle’s Vice President of Java Client Development, Nandini Ramani, provides the keys to unlock the mysteries of JavaFX 2.0 in her Java Magazine interview. Look for the JavaFX community to grow and flourish in coming years.

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• Personal search – the future of search

  - by jamiet

  [Four months ago I wrote a meandering blog post on another blogging site entitled Personal search – the future of search. The points I made therein are becoming more relevant to what I'm reading about and hoping to get involved in in the future so I'm re-posting here to a wider audience to hopefully get some more feedback and guage reaction to it. This has been prompted by the book Pull by David Siegel that is forming my current holiday reading (recommended to me by a commenter on my previous post Interesting things – Twitter annotations and your phone as a web server) and in particular by Siegel's notion of us all in the future having a personal online data vault.] My one-time colleague Paul Dawson recently wrote an article called The Future of Search and in it he proposed some interesting ideas. Some choice quotes: The growth of Chinese search giant Baidu is an indicator that fully localised and tailored content and offerings have great traction with local audiences This trend is already driving an increase in the use of specialist searches … Look at how Farecast is now integrated into Bing for example, or how Flightstats is now integrated into Google. Search does not necessarily have to begin with a keyword, but could start instead with a click or a touch. Take a look at Retrievr. Start drawing a picture in the box and see what happens. This is certainly search without the need for typing in keywords search technology has advanced greatly in recent years. The recent launch of Microsoft Live Labs’ Pivot has given us a taste of what we can expect to see in the future This really got me thinking about where search might go in the future and as my mind wandered I realised that as the amount of data that we collect about ourselves increases so too will the need and the desire to search it. The amount of electronic data that exists about each and every person is increasing and in the near future I fully expect that we are going to be able to store personal data such as: A history of our location (in fact Google Latitude already offers this facility) Recordings of all our phone conversations Health information history (weight, blood pressure etc…) Energy usage Spending history What films we watch, what radio stations we listen to Voting history Of course, most of this stuff is already stored somewhere but crucially we don’t have easy access to it. My utilities supplier knows how much electricity I’m using but if I want to know for myself I have to go and dig through my statements (assuming I have kept them). Similarly my doctor probably has ready access to all of my health records, my bank knows exactly what I have spent my money on, my cable supplier knows what I watch on TV and my mobile phone supplier probably knows exactly where I am and where I’ve been for the past few years. Strange then that none of this electronic information is available to me in a way that I can really make use of it; after all, its MY information. Its MY data. I created it. That is set to change. As technologies mature and customers become more technically cognizant they will demand more access to the data that companies hold about them. The companies themselves will realise the benefit that they derive from giving users what they want and will embrace ways of providing it. As a result the amount of data that we store about ourselves is going to increase exponentially and the desire to search and derive value from that data is going to grow with it; we are about to enter the era of the “personal datastore” and we will want, and need, to search through it in order to make sense of it all. Its interesting then that today when we think of search we think of search engines and yet in these personal datastores we’re referring to data that search engines can’t touch because WE own it and we (hopefully) choose to keep it private. Someone, I know not who, is going to lead in this space by making it easy for us to search our data and retrieve information that we have either forgotten or maybe didn’t even know in the first place. We will learn new things about ourselves and about our habits; we will share these findings with whomever we choose; we will compare what we discover with others; we will collaborate for mutual benefit and, most of all, we will educate ourselves as to how to live our lives better. Search will be the means to that end, it will enable us to make sense of the wealth of information that we will collect day in day out. The future of search is personal, why would we be interested in anything else? @Jamiet Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• ORA-4030 Troubleshooting

  - by [email protected]

  QUICKLINK: Note 399497.1 FAQ ORA-4030 Note 1088087.1 : ORA-4030 Diagnostic Tools [Video]   Have you observed an ORA-0430 error reported in your alert log? ORA-4030 errors are raised when memory or resources are requested from the Operating System and the Operating System is unable to provide the memory or resources.   The arguments included with the ORA-4030 are often important to narrowing down the problem. For more specifics on the ORA-4030 error and scenarios that lead to this problem, see Note 399497.1 FAQ ORA-4030.   Looking for the best way to diagnose? There are several available diagnostic tools (error tracing, 11g Diagnosibility, OCM, Process Memory Guides, RDA, OSW, diagnostic scripts) that collectively can prove powerful for identifying the cause of the ORA-4030.    Error Tracing   The ORA-4030 error usually occurs on the client workstation and for this reason, a trace file and alert log entry may not have been generated on the server side.  It may be necessary to add additional tracing events to get initial diagnostics on the problem. To setup tracing to trap the ORA-4030, on the server use the following in SQLPlus: alter system set events '4030 trace name heapdump level 536870917;name errorstack level 3';Once the error reoccurs with the event set, you can turn off  tracing using the following command in SQLPlus:alter system set events '4030 trace name context off; name context off';NOTE:   See more diagnostics information to collect in Note 399497.1  11g DiagnosibilityStarting with Oracle Database 11g Release 1, the Diagnosability infrastructure was introduced which places traces and core files into a location controlled by the DIAGNOSTIC_DEST initialization parameter when an incident, such as an ORA-4030 occurs.  For earlier versions, the trace file will be written to either USER_DUMP_DEST (if the error was caught in a user process) or BACKGROUND_DUMP_DEST (if the error was caught in a background process like PMON or SMON). The trace file may contain vital information about what led to the error condition.    Note 443529.1 11g Quick Steps to Package and Send Critical Error Diagnostic Informationto Support[Video]  Oracle Configuration Manager (OCM) Oracle Configuration Manager (OCM) works with My Oracle Support to enable proactive support capability that helps you organize, collect and manage your Oracle configurations. Oracle Configuration Manager Quick Start Guide Note 548815.1: My Oracle Support Configuration Management FAQ Note 250434.1: BULLETIN: Learn More About My Oracle Support Configuration Manager    General Process Memory Guides   An ORA-4030 indicates a limit has been reached with respect to the Oracle process private memory allocation.    Each Operating System will handle memory allocations with Oracle slightly differently. Solaris     Note 163763.1Linux       Note 341782.1IBM AIX   Notes 166491.1 and 123754.1HP           Note 166490.1Windows Note 225349.1, Note 373602.1, Note 231159.1, Note 269495.1, Note 762031.1Generic    Note 169706.1   RDAThe RDA report will show more detailed information about the database and Server Configuration. Note 414966.1 RDA Documentation Index Download RDA -- refer to Note 314422.1 Remote Diagnostic Agent (RDA) 4 - Getting Started OS Watcher (OSW)This tool is designed to gather Operating System side statistics to compare with the findings from the database.  This is a key tool in cases where memory usage is higher than expected on the server while not experiencing ORA-4030 errors currently. Reference more details on setup and usage in Note 301137.1 OS Watcher User Guide Diagnostic Scripts   Refer to Note 1088087.1 : ORA-4030 Diagnostic Tools [Video] Common Causes/Solutions The ORA-4030 can occur for a variety of reasons.  Some common causes are:   * OS Memory limit reached such as physical memory and/or swap/virtual paging.   For instance, IBM AIX can experience ORA-4030 issues related to swap scenarios.  See Note 740603.1 10.2.0.4 not using large pages on AIX for more on that problem. Also reference Note 188149.1 for pointers on 10g and stack size issues.* OS limits reached (kernel or user shell limits) that limit overall, user level or process level memory * OS limit on PGA memory size due to SGA attach address           Reference: Note 1028623.6 SOLARIS How to Relocate the SGA* Oracle internal limit on functionality like PL/SQL varrays or bulk collections. ORA-4030 errors will include arguments like "pl/sql vc2" "pmucalm coll" "pmuccst: adt/re".  See Coding Pointers for pointers on application design to get around these issues* Application design causing limits to be reached* Bug - space leaks, heap leaks   ***For reference to the content in this blog, refer to Note.1088267.1 Master Note for Diagnosing ORA-4030

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• URL Routing in ASP.NET 4.0

  In the .NET Framework 3.5 SP1, Microsoft introduced ASP.NET Routing, which decouples the URL of a resource from the physical file on the web server. With ASP.NET Routing you, the developer, define routing rules map route patterns to a class that generates the content. For example, you might indicate that the URL Categories/CategoryName maps to a class that takes the CategoryName and generates HTML that lists that category's products in a grid. With such a mapping, users could view products for the Beverages category by visiting www.yoursite.com/Categories/Beverages. In .NET 3.5 SP1, ASP.NET Routing was primarily designed for ASP.NET MVC applications, although as discussed in Using ASP.NET Routing Without ASP.NET MVC it is possible to implement ASP.NET Routing in a Web Forms application, as well. However, implementing ASP.NET Routing in a Web Forms application involves a bit of seemingly excessive legwork. In a Web Forms scenario we typically want to map a routing pattern to an actual ASP.NET page. To do so we need to create a route handler class that is invoked when the routing URL is requested and, in a sense, dispatches the request to the appropriate ASP.NET page. For instance, to map a route to a physical file, such as mapping Categories/CategoryName to ShowProductsByCategory.aspx - requires three steps: (1) Define the mapping in Global.asax, which maps a route pattern to a route handler class; (2) Create the route handler class, which is responsible for parsing the URL, storing any route parameters into some location that is accessible to the target page (such as HttpContext.Items), and returning an instance of the target page or HTTP Handler that handles the requested route; and (3) writing code in the target page to grab the route parameters and use them in rendering its content. Given how much effort it took to just read the preceding sentence (let alone write it) you can imagine that implementing ASP.NET Routing in a Web Forms application is not necessarily the most straightforward task. The good news is that ASP.NET 4.0 has greatly simplified ASP.NET Routing for Web Form applications by adding a number of classes and helper methods that can be used to encapsulate the aforementioned complexity. With ASP.NET 4.0 it's easier to define the routing rules and there's no need to create a custom route handling class. This article details these enhancements. Read on to learn more! Read More >

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• How to Assign a Static IP to an Ubuntu 10.04 Desktop Computer

  - by Mysticgeek

  If you have a home network with several computers, assigning them static IP addresses can make troubleshooting easier. Today we take a look at switching from DHCP to a static IP in Ubuntu. Assign a Static IP Using Static IPs prevents address conflicts between machines and can allow easier access to them. If you have a small home network and are satisfied with the machines getting their IP address automatically via DHCP, there won’t be anything gained by using static addresses. Using Static IPs isn’t necessarily for the average user, but if you’re a geek who wants to know the address assigned to each machine, it can allow for faster troubleshooting.  To change your Ubuntu machine to a Static IP go to System \ Preferences \ Network Connections. In our example, we’re on a wired system so click on the Wired tab, then select Auto eth0 and click on Edit. Select the IPv4 settings tab, change Method to Manual, click the Add button. Then type in the Static IP Address, Subnet Mask, DNS Servers, and Default Gateway. Then click Apply when you’re finished. Make sure to hit Enter after typing in the Default Gateway otherwise it will revert back to 0.0.0.0 You’ll need to enter in your admin password before the changes go into affect. To verify the changes have been made successfully launch a Terminal session and type in ifconfig at the command prompt, or follow these directions. You also might want to ping the address from another machine to make sure everything is communicating. If you want to assign a Static IP to your Windows machines, check out our article on how to assign a Static IP on Windows systems (make sure to browse the comments as our readers have some good suggestions).  Whether you have a small office or home network set up with a server and several machines, using a Static IP on each device can help you manage them easily. Again, it isn’t for everyone as it really depends on how your network is setup and the way you use it. Similar Articles Productive Geek Tips Change Ubuntu Desktop from DHCP to a Static IP AddressAllow Remote Control To Your Desktop On UbuntuAssign Custom Shortcut Keys on Ubuntu LinuxKeyboard Ninja: 21 Keyboard Shortcut ArticlesChange Ubuntu Server from DHCP to a Static IP Address TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips HippoRemote Pro 2.2 Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server TubeSort: YouTube Playlist Organizer XPS file format & XPS Viewer Explained Microsoft Office Web Apps Guide Know if Someone Accessed Your Facebook Account Shop for Music with Windows Media Player 12 Access Free Documentaries at BBC Documentaries

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• OrbitFX: JavaFX 8 3D & NetBeans Platform in Space!

  - by Geertjan

  Here is a collection of screenshots from a proof of concept tool being developed by Nickolas Sabey and Sean Phillips from a.i. solutions. Before going further, read a great new article here written on java.net by Kevin Farnham, in light of the Duke's Choice Award (DCA) recently received at JavaOne 2013 by the a.i. solutions team. Here's Sean receiving the award on behalf of the a.i. solutions team, surrounded by the DCA selection committee and other officials: They won the DCA for helping facilitate and deploy the 2014 launch of NASA's Magnetospheric Multiscale mission, using JDK 7, the NetBeans Platform, and JavaFX to create the GEONS Ground Support System, helping reduce software development time by approximately 35%. The prototype tool that Nicklas and Sean are now working on uses JavaFX 3D with the NetBeans Platform and is nicknamed OrbitFX. Much of the early development is being done to experiment with different patterns, so that accuracy is currently not the goal. For example, you'll notice in the screenshots that the Earth is really close to the Sun, which is obviously not correct. The screenshots are generated using Java 8 build 111, together with NetBeans Platform 7.4. Inspired by various JavaOne demos using JavaFX 3D, Nick began development integrating them into their existing NetBeans Platform infrastructure. The 3D scene showing the Sun and Earth objects is all JavaFX 8 3D, demonstrating the use of Phong Material support, along with multiple light and camera objects. Each JavaFX component extends a JFXPanel type, so that each can easily be added to NetBeans Platform TopComponents. Right-clicking an item in the explorer view offers a context menu that animates and centers the 3D scene on the selected celestial body.  With each JavaFX scene component wrapped in a JFXPanel, they can easily be integrated into a NetBeans Platform Visual Library scene.  In this case, Nick and Sean are using an instance of their custom Slipstream PinGraphScene, which is an extension of the NetBeans Platform VMDGraphScene. Now, via the NetBeans Platform Visual Library, the OrbitFX celestial body viewer can be used in the same space as a WorldWind viewer, which is provided by a previously developed plugin. "This is a clear demonstration of the power of the NetBeans Platform as an application development framework," says Sean Phillips. "How else could you have so much rich application support placed literally side by side so easily?"

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• Backup Azure Tables, schedule Azure scripts&hellip; and more

  - by Herve Roggero

  Well – months of effort are now officially over… or should I say it’s just the beginning?   Enzo Cloud Backup 2.0 (beta) is now officially out!!! This tool will let you do the following: * Backup SQL Database (and SQL Server to a limited extend) * Backup Azure Tables * Restore SQL Backups into another SQL environment * Restore Azure Tables in Azure Storage, or SQL Environment * Manage and schedule database maintenance scripts * Drop database schema containers (with preview) for SaaS environments * Receive alerts (SMTP) when operations complete or fail That’s it at a high level… but you need to see the flexibility around these features. For example you can select a specific backup strategy for Azure Tables allowing faster backup operations when partition keys use GUIDs. You can also call custom stored procedures during the restore operation of Azure Tables, allowing you to transform the data along the way. You can also set a performance threshold during Azure Table backup operations to help you control possible throttling conditions in your Storage Account. Regarding database scripts, you can now define T-SQL scripts and schedule them for execution in a specific order. You can also tell Enzo to execute a pre and post script during Azure Table restore operations against a SQL environment. The backup operation now supports backing up to multiple devices at the same time. So you can execute a backup request to both a local file, and a blob at the same time, guaranteeing that both will contain the exact same data. And due to the level of options that are available, you can save backup definitions for later reuse. The screenshot below backs up Azure Tables to two devices (a blob and a SQL Database). You can also manage your database schemas for SaaS environments that use schema containers to separate customer data. This new edition allows you to see how many objects you have in each schema, backup specific schemas, and even drop all objects in a given schema. For example the screenshot below shows that the EnzoLog database has 4 user-defined schemas, and the AFA schema has 5 tables and 1 module (stored proc, function, view…). Selecting the AFA schema and trying to delete it will prompt another screen to show which objects will be deleted. As you can see, Enzo Cloud Backup provides amazing capabilities that can help you safeguard your data in SQL Database and Azure Tables, and give you advanced management functions for your Azure environment. Download a free trial today at http://www.bluesyntax.net.

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• C# 4.0: Covariance And Contravariance In Generics

  - by Paulo Morgado

  C# 4.0 (and .NET 4.0) introduced covariance and contravariance to generic interfaces and delegates. But what is this variance thing? According to Wikipedia, in multilinear algebra and tensor analysis, covariance and contravariance describe how the quantitative description of certain geometrical or physical entities changes when passing from one coordinate system to another.(*) But what does this have to do with C# or .NET? In type theory, a the type T is greater (>) than type S if S is a subtype (derives from) T, which means that there is a quantitative description for types in a type hierarchy. So, how does covariance and contravariance apply to C# (and .NET) generic types? In C# (and .NET), variance applies to generic type parameters and not to the resulting generic type. A generic type parameter is: covariant if the ordering of the generic types follows the ordering of the generic type parameters: Generic<T> = Generic<S> for T = S. contravariant if the ordering of the generic types is reversed from the ordering of the generic type parameters: Generic<T> = Generic<S> for T = S. invariant if neither of the above apply. If this definition is applied to arrays, we can see that arrays have always been covariant because this is valid code: object[] objectArray = new string[] { "string 1", "string 2" }; objectArray[0] = "string 3"; objectArray[1] = new object(); However, when we try to run this code, the second assignment will throw an ArrayTypeMismatchException. Although the compiler was fooled into thinking this was valid code because an object is being assigned to an element of an array of object, at run time, there is always a type check to guarantee that the runtime type of the definition of the elements of the array is greater or equal to the instance being assigned to the element. In the above example, because the runtime type of the array is array of string, the first assignment of array elements is valid because string = string and the second is invalid because string = object. This leads to the conclusion that, although arrays have always been covariant, they are not safely covariant – code that compiles is not guaranteed to run without errors. In C#, the way to define that a generic type parameter as covariant is using the out generic modifier: public interface IEnumerable<out T> { IEnumerator<T> GetEnumerator(); } public interface IEnumerator<out T> { T Current { get; } bool MoveNext(); } Notice the convenient use the pre-existing out keyword. Besides the benefit of not having to remember a new hypothetic covariant keyword, out is easier to remember because it defines that the generic type parameter can only appear in output positions — read-only properties and method return values. In a similar way, the way to define a type parameter as contravariant is using the in generic modifier: public interface IComparer<in T> { int Compare(T x, T y); } Once again, the use of the pre-existing in keyword makes it easier to remember that the generic type parameter can only be used in input positions — write-only properties and method non ref and non out parameters. Because covariance and contravariance apply only to the generic type parameters, a generic type definition can have both covariant and contravariant generic type parameters in its definition: public delegate TResult Func<in T, out TResult>(T arg); A generic type parameter that is not marked covariant (out) or contravariant (in) is invariant. All the types in the .NET Framework where variance could be applied to its generic type parameters have been modified to take advantage of this new feature. In summary, the rules for variance in C# (and .NET) are: Variance in type parameters are restricted to generic interface and generic delegate types. A generic interface or generic delegate type can have both covariant and contravariant type parameters. Variance applies only to reference types; if you specify a value type for a variant type parameter, that type parameter is invariant for the resulting constructed type. Variance does not apply to delegate combination. That is, given two delegates of types Action<Derived> and Action<Base>, you cannot combine the second delegate with the first although the result would be type safe. Variance allows the second delegate to be assigned to a variable of type Action<Derived>, but delegates can combine only if their types match exactly. If you want to learn more about variance in C# (and .NET), you can always read: Covariance and Contravariance in Generics — MSDN Library Exact rules for variance validity — Eric Lippert Events get a little overhaul in C# 4, Afterward: Effective Events — Chris Burrows Note: Because variance is a feature of .NET 4.0 and not only of C# 4.0, all this also applies to Visual Basic 10.

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• What&rsquo;s new in VS.10 &amp; TFS.10?

  - by johndoucette

  Getting my geek on… I have decided to call the products VS.10 (Visual Studio 2010), TP.10 (Test Professional 2010),  and TFS.10 (Team Foundation Server 2010) Thanks Neno Loje. What's new in Visual Studio & Team Foundation Server 2010? Focusing on Visual Studio Team System (VSTS) ALM-related parts: Visual Studio Ultimate 2010 NEW: IntelliTrace® (aka the historical debugger) NEW: Architecture Tools New Project Type: Modeling Project UML Diagrams UML Use Case Diagram UML Class Diagram UML Sequence Diagram (supports reverse enginneering) UML Activity Diagram UML Component Diagram Layer Diagram (with Team Build integration for layer validation) Architecuture Explorer Dependency visualization DGML Web & Load Tests Visual Studio Premium 2010 NEW: Architecture Tools Read-only model viewer Development Tools Code Analysis New Rules like SQL Injection detection Rule Sets Code Profiler Multi-Tier Profiling JScript Profiling Profiling applications on virtual machines in sampling mode Code Metrics Test Tools Code Coverage NEW: Test Impact Analysis NEW: Coded UI Test Database Tools (DB schema versioning & deployment) Visual Studio Professional 2010 Debuger Mixed Mode Debugging for 64-bit Applications Export/Import of Breakpoints and data tips Visual Studio Test Professional 2010 Microsoft Test Manager (MTM, formerly known as "Camano")) Fast Forward Testing Visual Studio Team Foundation Server 2010 Work Item Tracking and Project Management New MSF templatesfor Agile and CMMI (V 5.0) Hierarchical Work Items Custom Work Item Link Types Ready to use Excel agile project management workbooks for managing your backlogs (including capacity planing) Convert Work Item query to an Excel report MS Excel integration Support for Work Item hierarchies Formatting is preserved after doing a 'Refresh' MS Project integration Hierarchy and successor/predecessor info is now synchronized NEW: Test Case Management Version Control Public Workspaces Branch & Merge Visualization Tracking of Changesets & Work Items Gated Check-In Team Build Build Controllers and Agents Workflow 4-based build process NEW: Lab Management (only a pre-release is avaiable at the moment!) Project Portal & Reporting Dashboards (on SharePoint Portal) Burndown Chart TFS Web Parts (to show data from TFS) Administration & Operations Topology enhancements Application tier network load balancing (NLB) SQL Server scale out Improved Sharepoint flexibility Report Server flexibility Zone support Kerberos support Separation of TFS and SQL administration Setup Separate install from configure Improved installation wizards Optional components Simplified account requirements Improved Reporting Services configuration Setup consolidation Upgrading from previous TFS versions Improved IIS flexibility Administration Consolidation of command line tools User rename support Project Collections Archive/restore individual project collections Move Team Project Collections Server consolidation Team Project Collection Split Team Project Collection Isolation Server request cancellation Licensing: TFS server license included in MSDN subscriptions Removed features (former features not part of Visual Studio 2010): Debug » Start With Application Verifier Object Test Bench IntelliSense for C++ / CLI Debugging support for SQL 2000

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• 2012 Oracle Fusion Innovation Awards - Part 2

  - by Michelle Kimihira

  Author: Moazzam Chaudry Continuing from Friday's blog on 2012 Oracle Fusion Innovation Awards, this blog (Part 2) will provide more details around the customers. It was a tremendous honor to be in single room of winners. We only wish we could have had more time to share stories from all the winners.  We received great insight from all the innovative solutions that our customers deploy and would like to share them broadly, so that others can benefit from best practices. There was a customer panel session joined by Ingersoll Rand, Nike and Motability and here is what was discussed: Barry Bonar, Enterprise Architect from Ingersoll Rand shared details around their solution, comprised of Oracle Exalogic, Oracle WebLogic Server and Oracle SOA Suite. This combined solutoin enabled their business transformation to increase decision-making, speed and efficiency, resulting in 40% reduced IT spend, 41X Faster response time and huge cost savings. Ashok Balakrishnan, Architect from Nike shared how they leveraged Oracle Coherence to analyze their digital "footprint" of activities. This helps them compete, collaborate and compare athletic data over time. Lastly, Ashley Doodly, Head of IT from Motability shared details around their solution compromised of Oracle SOA Suite, Service Bus, ADF, Coherence, BO and E-Business Suite. This solution helped Motability achieve 100% ROI within the first few months, performance in seconds vs. 10's of minutes and tremendous improvement in throughput that increased up to 50%.  This year's winners by category are: Oracle Exalogic Customer Results using Fusion Middleware Netshoes ATG on Exalogic: 6X Reduced H/W foot print, 6.2X increased throughput and 3 weeks time to market Claro Part of America Movil, running mission critical Java Application on Exalogic with 35X Faster Java response time, 5X Throughput Underwriters Laboratories Exalogic as an Apps Consolidation platform to power tremendous growth Ingersoll Rand EBS on Exalogic: Up to 40% Reduction in overall IT budget, 3x reduced foot print Oracle Cloud Application Foundation Customer Results using Fusion Middleware  Mazda Motor Corporation Tuxedo ART Batch runtime environment to migrate their batch apps on new open environment and reduce main frame cost. HOTELBEDS Technology Open Source to WebLogic transformation Globalia Corporation Introduced Oracle Coherence to fully reengineer DTH system and provide multiple business and technical benefits Nike Nike+, digital sports platform, has 8M users and is expecting an 5X increase in users, many of who will carry multiple devices that frequently sync data with the Digital Sport platform Comcast Corporation The solution is expected to increase availability, continuity, performance, and simplify and make the code at the application layer more flexible. Oracle SOA and Oracle BPM Customer Results using Fusion Middleware NTT Docomo Network traffic solution based on Oracle event processing and coherence - massive in scale: 12M users (50M in future) - 800,000 events/sec. Schneider National, Inc. SOA/B2B/ADF/Data Integration to orchestrate key order processes across Siebel, OTM & EBS.  Platform runs 60M trans/day and  50 million composite SOA instances per day across 10G and 11G Amadeus Oracle BPM solution: Business Rules and processes vary across local (80), regional (~10) and corporate approval process. Up to 10 levels of approval. Plans to deploy across 20+ markets Navitar SOA solution integrates a fully non-Oracle legacy application/ERP environment using Oracle’s SOA Suite and Oracle AIA Foundation Pack. Motability Uses SOA Suite to synchronize data across the systems and to manage the vehicle remarketing process Oracle WebCenter Customer Results using Fusion Middleware  News Limited Single platform running websites for 50% of Australia's newspapers University of Louisville “Facebook for Medicine”: Oracle Webcenter platform and Oracle BIEE to analyze patient test data and uncover potential health issues. Expecting annualized ROI of 277% China Mobile Jiangsu Company portal (25k users) to drive collaboration & productivity Life Technologies Portal for remotely monitoring & repairing biotech instruments LA Dept. of Water & Power Oracle WebCenter Portal to power ladwp.com on desktop and mobile for 1.6million users Oracle Identity Management Customer Results using Fusion Middleware Education Testing Service Identity Management platform for provisioning & SSO of 6 million GRE, GMAT, TOEFL customers Avea Oracle Identity Manager allowing call center personnel to quickly change Identity Profile to handle varying call loads based on a user self service interface. Decreased Admin Cost by 30% Oracle Data Integration Customer Results using Fusion Middleware Raymond James Near real-time integration for improved systems (throughput & performance) and enhanced operational flexibility in a 24 X 7 environment Wm Morrison Supermarkets Electronic Point of Sale integration handling over 80 million transactions a day in near real time (15 min intervals) Oracle Application Development Framework and Oracle Fusion Development Customer Results using Fusion Middleware Qualcomm Incorporated Solution providing  immediate business value enabling a self-service model necessary for growing the new customer base, an increase in customer satisfaction, reduced “time-to-deliver” Micros Systems, Inc. ADF, SOA Suite, WebCenter  enables services that include managing distribution of hotel rooms availability and rates to channels such as Hotel Web-site, Expedia, etc. Marfin Egnatia Bank A new web 2.0 UI provides a much richer experience through the ADF solution with the end result being one of boosting end-user productivity    Business Analytics (Oracle BI, Oracle EPM, Oracle Exalytics) Customer Results using Fusion Middleware INC Research Self-service customer portal delivering 5–10% of the overall revenue - expected to grow fast with the BI solution Experian Reduction in Time to Complete the Financial Close Process Hologic Inc Solution, saving months of decision-making uncertainty! We look forward to seeing many more innovative nominations. The nominatation process for 2013 begins in April 2013.    Additional Information: Blog: Oracle WebCenter Award Winners Blog: Oracle Identity Management Winners Blog: Oracle Exalogic Winners Blog: SOA, BPM and Data Integration will be will feature award winners in its respective areas this week Subscribe to our regular Fusion Middleware Newsletter Follow us on Twitter and Facebook

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• A C# implementation of the CallStream pattern

  - by Bertrand Le Roy

  Dusan published this interesting post a couple of weeks ago about a novel JavaScript chaining pattern: http://dbj.org/dbj/?p=514 It’s similar to many existing patterns, but the syntax is extraordinarily terse and it provides a new form of friction-free, plugin-less extensibility mechanism. Here’s a JavaScript example from Dusan’s post: CallStream("#container") (find, "div") (attr, "A", 1) (css, "color", "#fff") (logger); The interesting thing here is that the functions that are being passed as the first argument are arbitrary, they don’t need to be declared as plug-ins. Compare that with a rough jQuery equivalent that could look something like this: $.fn.logger = function () { /* ... */ } $("selector") .find("div") .attr("A", 1) .css("color", "#fff") .logger(); There is also the “each” method in jQuery that achieves something similar, but its syntax is a little more verbose. Of course, that this pattern can be expressed so easily in JavaScript owes everything to the extraordinary way functions are treated in that language, something Douglas Crockford called “the very best part of JavaScript”. One of the first things I thought while reading Dusan’s post was how I could adapt that to C#. After all, with Lambdas and delegates, C# also has its first-class functions. And sure enough, it works really really well. After about ten minutes, I was able to write this: CallStreamFactory.CallStream (p => Console.WriteLine("Yay!")) (Dump, DateTime.Now) (DumpFooAndBar, new { Foo = 42, Bar = "the answer" }) (p => Console.ReadKey()); Where the Dump function is: public static void Dump(object options) { Console.WriteLine(options.ToString()); } And DumpFooAndBar is: public static void DumpFooAndBar(dynamic options) { Console.WriteLine("Foo is {0} and bar is {1}.", options.Foo, options.Bar); } So how does this work? Well, it really is very simple. And not. Let’s say it’s not a lot of code, but if you’re like me you might need an Advil after that. First, I defined the signature of the CallStream method as follows: public delegate CallStream CallStream (Action<object> action, object options = null); The delegate define a call stream as something that takes an action (a function of the options) and an optional options object and that returns a delegate of its own type. Tricky, but that actually works, a delegate can return its own type. Then I wrote an implementation of that delegate that calls the action and returns itself: public static CallStream CallStream (Action<object> action, object options = null) { action(options); return CallStream; } Pretty nice, eh? Well, yes and no. What we are doing here is to execute a sequence of actions using an interesting novel syntax. But for this to be actually useful, you’d need to build a more specialized call stream factory that comes with some sort of context (like Dusan did in JavaScript). For example, you could write the following alternate delegate signature that takes a string and returns itself: public delegate StringCallStream StringCallStream(string message); And then write the following call stream (notice the currying): public static StringCallStream CreateDumpCallStream(string dumpPath) { StringCallStream str = null; var dump = File.AppendText(dumpPath); dump.AutoFlush = true; str = s => { dump.WriteLine(s); return str; }; return str; } (I know, I’m not closing that stream; sure; bad, bad Bertrand) Finally, here’s how you use it: CallStreamFactory.CreateDumpCallStream(@".\dump.txt") ("Wow, this really works.") (DateTime.Now.ToLongTimeString()) ("And that is all."); Next step would be to combine this contextual implementation with the one that takes an action parameter and do some really fun stuff. I’m only scratching the surface here. This pattern could reveal itself to be nothing more than a gratuitous mind-bender or there could be applications that we hardly suspect at this point. In any case, it’s a fun new construct. Or is this nothing new? You tell me… Comments are open :)

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• 5 Useful Wordpress Plugins For Google Adsense

  - by Jyoti

  Google Adsense has become the most popular online contextual advertising program and proper custom integration with Wordpress can help to increase Adsense earnings. Now on this post we have describe 5 useful wordpress plugin for google adsense. Few weeks ago we did a "10 Wordpress Plugins For Google Adsense ". Wordpress allows bloggers to easily integrate Google Adsense inside wordpress using plugins. Adsense Integrator : The Adsense Integrator plugin supports lot of programs other then adsense like AdBrite, AffiliateBOT, SHAREASALE, LinkShare, ClickBank, Oxado, Adpinion, AdGridWork, Adroll, Commission Junction, CrispAds, ShoppingAds, Yahoo!PN so this can be used when you are looking to have adsense as well as other alternatives. The rest of the features of the plugin are same where you give your adsense code into options field and it get inserted into blog posts. All In One Adsense And YPN : This is one of the most powerful adsense plugin for wordpress. Jut like other plugins, you can use this to insert your ads in the post but the plugin has some really good features like randomness which shows ad at random location in your blog which reduces ad blindness for viewers. You can also stop ads being shown on some pages using tags. Adsense Now : Other then the previous plugins , you can also give it a try to Adsense now. I haven’t used it (I have only used the first two) so its difficult to comment on it. It looks to be a lightweight plugin which insert adsense ads between posts and in posts body. Adsense Manager : Adsense Manager is one of the most popular and used plugin to manage adsense in wordpress blogs. Infact its newer version not only supports adsense, it also supports various other programs like adbrite, Commission Junction, YPN etc which makes it very powerful ad management plugin. You can inject adsense code anywhere in your blog posts as well as can put in different regions of your blog. Easy Adsense : Easy adsense is one of the new wordpress adsense plugin and that is why more feature rich. You can have different code for different themes using this plugin. It also support link units. To know all features, check out the plugin page.

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• SQL SERVER – The Story of a Lesser Known Startup Parameter in SQL Server – Guest Post by Balmukund Lakhani

  - by Pinal Dave

  This is a fantastic blog post from my dear friend Balmukund ( blog | twitter | facebook ). He had presented a fantastic session in our last UG and there were lots of requests from attendees that he blogs about it. Well, here is the blog post about the same very popular UG session. Let us read the entire blog post in the voice of the Balmukund himself. During my last session in SQL Bangalore User Group (Facebook) meeting, I was lucky enough to deliver a session on SQL Server Startup issue. The name of the session was “SQL Engine Starting Trouble – How to start?” From the feedback, I realized that one of the “not well known” startup parameter is “-m”. Okay, you might say “I know that this is used to start the SQL in single user mode”. But what you might not know is that you can pass a string with -m which has special meaning and use. I have used this parameter in my blog here but looks like not many of you have seen that. It happens most of the time when we want to start SQL Server in single user mode, someone else makes connection before you can. The only choice you have is to repeat same process again till you succeed. Some smart DBAs may disable the remote network protocols (TCP/IP and Named Pipes) of SQL Instance and allow only local connections to SQL. Once the activity is complete, our dear smart DBA has to remember to re-enable network protocols. Sometimes, it may be a local service or application getting connection to SQL before we can. There is a better way to deal with it. Yes, you have guessed it correctly: -m parameter which a string. Since I work with SQL Product Support team, I may know little more undocumented commands and parameters, but this is not an undocumented stuff. It’s already documented in books online. So in this blog, I am going to show a demo of its usage. As documentation shows, “Do not use this option as a security feature.” So please read this blog as knowledge enhancer and troubleshooting issues not security feature. In my laptop, I have a default instance of SQL Server 2012 and here is what we would in the configuration manager. Now, I would go ahead and stop SQL Service by selecting SQL Server (MSSQLServer) > Right Click > Stop. There are multiple ways to start SQL with startup parameter. 1) Use Net Start Command from command prompt Net Start MSSQLServer /mSQLCMD The above command is the simplest way to add startup parameter to SQL. This parameter would be cleared once we stop and start SQL. 2) Add Startup Parameter via configuration manager. Step is already listed here. We need to add -mSQLCMD If we compare 1 and 2, it’s clear that unless we modify startup parameter and remove -m, it would be in effect. 3) Start SQL Service via command line SQLServr.exe –mSQLCMD –s<InstanceName> Wait, what does SQLCMD mean with /m? It’s the instruction to SQL that start SQL Server in Single User Mode and allow only the application which is SQLCMD. Any other application would fail with Login Failed for User Error message. It would be important to note that string is case sensitive. This value should be picked up from application_name column from sys.dm_exec_sessions. I have made a connection using SQLCMD and as we can see it comes as upper case “SQLCMD”. If we want only management studio query windows to connect then we need to give -m” Microsoft SQL Server Management Studio – Query” as startup parameter. In below example, I have given it as SQLCMd (lower case d at the end) and we would notice that we would not be able to connect to SQL Instance. Above proves that parameter works as expected and it’s case sensitive. Error Log would show below information. How to get error log location? I have already blogged about it. Hope you have learned something new. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL, Technology

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• Odd Profiler Results with EF4

  - by AjarnMark

  I have been doing some testing of using the Microsoft Entity Framework 4 with stored procedures and ran across some really odd results in SQL Server Profiler. The application that is running which uses Entity Framework 4 is a simple Web Application written in C#, and the Entity Data Model is actually contained in a referenced class library of its own.  I’ll write more about my experiences with this later.  For now the question is, why does SQL Profiler think that the stored procedure is running in Master, and not in my application database? While analyzing the effects of using custom helper methods on my EDM classes to call the stored procedure, I decided to run Profiler while I stepped through the code so that I had a clear understanding of exactly when and what calls were made to the SQL Server.  I ran Profiler switching back and forth between the TSQL and TSQL_SP templates.  However, to reduce the amount of results rows I needed to wade through, I set a filter on DatabaseID to be equal to my application’s database.  Each time I ran this, the only thing that I saw was an Audit:Login to the database, but no procedure or T-SQL statements executed, yet I was definitely getting results back to my web page.  I tried other Profiler templates, still filtering on DatabaseID (tangent: I found, at least back in SQL 2000 Profiler, that filtering on DatabaseID was more reliable than filtering on DatabaseName.  Even though I’m now running SQL 2008, that habit sticks with me).  Still no results other than the Login.  Very weird! Finally, I decided to run Profiler with no filtering and discovered that that lines which represent my stored procedure and its T-SQL commands are all marked with DatabaseID = 1, which is Master.  Why in the world would that be?  My procedure is definitely in the application database, and not in Master, and there is nothing funny about the call to the procedure evident in Profiler (i.e. it is not called as MyAppDB.dbo.MyProcName, but rather just dbo.MyProcName).  There must be something funny with the way the Entity Framework is wrapping this call, and I don’t like it…I don’t like it one bit.  My primary PROD server contains 40+ databases on it, and when I need to profile something, I expect to be able to filter based on DatabaseID (for the record, I displayed DatabaseName in my results, too, and it also shows Master). I find the same pattern of everything except the Login showing up as being in Master when I run my version that uses standard LINQ to Entities instead of stored procedures, so that suggests it is not my code, but rather something funny with SQL Server 2008 Profiler or the Entity Framework. If you have any ideas about why this might be so, please comment below.

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• SQL SERVER – Identify Numbers of Non Clustered Index on Tables for Entire Database

  - by pinaldave

  Here is the script which will give you numbers of non clustered indexes on any table in entire database. SELECT COUNT(i.TYPE) NoOfIndex, [schema_name] = s.name, table_name = o.name FROM sys.indexes i INNER JOIN sys.objects o ON i.[object_id] = o.[object_id] INNER JOIN sys.schemas s ON o.[schema_id] = s.[schema_id] WHERE o.TYPE IN ('U') AND i.TYPE = 2 GROUP BY s.name, o.name ORDER BY schema_name, table_name Here is the small story behind why this script was needed. I recently went to meet my friend in his office and he introduced me to his colleague in office as someone who is an expert in SQL Server Indexing. I politely said I am yet learning about Indexing and have a long way to go. My friend’s colleague right away said – he had a suggestion for me with related to Index. According to him he was looking for a script which will count all the non clustered on all the tables in the database and he was not able to find that on SQLAuthority.com. I was a bit surprised as I really do not remember all the details about what I have written so far. I quickly pull up my phone and tried to look for the script on my custom search engine and he was correct. I never wrote a script which will count all the non clustered indexes on tables in the whole database. Excessive indexing is not recommended in general. If you have too many indexes it will definitely negatively affect your performance. The above query will quickly give you details of numbers of indexes on tables on your entire database. You can quickly glance and use the numbers as reference. Please note that the number of the index is not a indication of bad indexes. There is a lot of wisdom I can write here but that is not the scope of this blog post. There are many different rules with Indexes and many different scenarios. For example – a table which is heap (no clustered index) is often not recommended on OLTP workload (here is the blog post to identify them), drop unused indexes with careful observation (here is the script for it), identify missing indexes and after careful testing add them (here is the script for it). Even though I have given few links here it is just the tip of the iceberg. If you follow only above four advices your ship may still sink. Those who wants to learn the subject in depth can watch the videos here after logging in. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Index, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Using MVP, how to create a view from another view, linked with the same model object

  - by Dinaiz

  Background We use the Model-View-Presenter design pattern along with the abstract factory pattern and the "signal/slot" pattern in our application, to fullfill 2 main requirements Enhance testability (very lightweight GUI, every action can be simulated in unit tests) Make the "view" totally independant from the rest, so we can change the actual view implementation, without changing anything else In order to do so our code is divided in 4 layers : Core : which holds the model Presenter : which manages interactions between the view interfaces (see bellow) and the core View Interfaces : they define the signals and slots for a View, but not the implementation Views : the actual implementation of the views When the presenter creates or deals with views, it uses an abstract factory and only knows about the view interfaces. It does the signal/slot binding between views interfaces. It doesn't care about the actual implementation. In the "views" layer, we have a concrete factory which deals with implementations. The signal/slot mechanism is implemented using a custom framework built upon boost::function. Really, what we have is something like that : http://martinfowler.com/eaaDev/PassiveScreen.html Everything works fine. The problem However, there's a problem I don't know how to solve. Let's take for example a very simple drag and drop example. I have two ContainersViews (ContainerView1, ContainerView2). ContainerView1 has an ItemView1. I drag the ItemView1 from ContainerView1 to ContainerView2. ContainerView2 must create an ItemView2, of a different type, but which "points" to the same model object as ItemView1. So the ContainerView2 gets a callback called for the drop action with ItemView1 as a parameter. It calls ContainerPresenterB passing it ItemViewB In this case we are only dealing with views. In MVP-PV, views aren't supposed to know anything about the presenter nor the model, right ? How can I create the ItemView2 from the ItemView1, not knowing which model object is ItemView1 representing ? I thought about adding an "itemId" to every view, this id being the id of the core object the view represents. So in pseudo code, ContainerPresenter2 would do something like itemView2=abstractWidgetFactory.createItemView2(); this.add(itemView2,itemView1.getCoreObjectId()) I don't get too much into details. That just work. The problem I have here is that those itemIds are just like pointers. And pointers can be dangling. Imagine that by mistake, I delete itemView1, and this deletes coreObject1. The itemView2 will have a coreObjectId which represents an invalid coreObject. Isn't there a more elegant and "bulletproof" solution ? Even though I never did ObjectiveC or macOSX programming, I couldn't help but notice that our framework is very similar to Cocoa framework. How do they deal with this kind of problem ? Couldn't find more in-depth information about that on google. If someone could shed some light on this. I hope this question isn't too confusing ...

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