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  • Why should you choose Oracle WebLogic 12c instead of JBoss EAP 6?

    - by Ricardo Ferreira
    In this post, I will cover some technical differences between Oracle WebLogic 12c and JBoss EAP 6, which was released a couple days ago from Red Hat. This article claims to help you in the evaluation of key points that you should consider when choosing for an Java EE application server. In the following sections, I will present to you some important aspects that most customers ask us when they are seriously evaluating for an middleware infrastructure, specially if you are considering JBoss for some reason. I would suggest that you keep the following question in mind while you are reading the points: "Why should I choose JBoss instead of WebLogic?" 1) Multi Datacenter Deployment and Clustering - D/R ("Disaster & Recovery") architecture support is embedded on the WebLogic Server 12c product. JBoss EAP 6 on the other hand has no direct D/R support included, Red Hat relies on third-part tools with higher prices. When you consider a middleware solution to host your business critical application, you should worry with every architectural aspect that are related with the solution. Fail-over support is one little aspect of a truly reliable solution. If you do not worry about D/R, your solution will not be reliable. Having said that, with Red Hat and JBoss EAP 6, you have this extra cost that will increase considerably the total cost of ownership of the solution. As we commonly hear from analysts, open-source are not so cheaper when you start seeing the big picture. - WebLogic Server 12c supports advanced LAN clustering, detection of death servers and have a common alert framework. JBoss EAP 6 on the other hand has limited LAN clustering support with no server death detection. They do not generate any alerts when servers goes down (only if you buy JBoss ON which is a separated technology, but until now does not support JBoss EAP 6) and manual intervention are required when servers goes down. In most cases, admin people must rely on "kill -9", "tail -f someFile.log" and "ps ax | grep java" commands to manage failures and clustering anomalies. - WebLogic Server 12c supports the concept of Node Manager, which is a separated process that runs on the physical | virtual servers that allows extend the administration of the cluster to WebLogic managed servers that are often distributed across multiple machines and geographic locations. JBoss EAP 6 on the other hand has no equivalent technology. Whole server instances must be managed individually. - WebLogic Server 12c Node Manager supports Coherence to boost performance when managing servers. JBoss EAP 6 on the other hand has no similar technology. There is no way to coordinate JBoss and infiniband instances provided by JBoss using high throughput and low latency protocols like InfiniBand. The Node Manager feature also allows another very important feature that JBoss EAP lacks: secure the administration. When using WebLogic Node Manager, all the administration tasks are sent to the managed servers in a secure tunel protected by a certificate, which means that the transport layer that separates the WebLogic administration console from the managed servers are secured by SSL. - WebLogic Server 12c are now integrated with OTD ("Oracle Traffic Director") which is a web server technology derived from the former Sun iPlanet Web Server. This software complements the web server support offered by OHS ("Oracle HTTP Server"). Using OTD, WebLogic instances are load-balanced by a high powerful software that knows how to handle SDP ("Socket Direct Protocol") over InfiniBand, which boost performance when used with engineered systems technologies like Oracle Exalogic Elastic Cloud. JBoss EAP 6 on the other hand only offers support to Apache Web Server with custom modules created to deal with JBoss clusters, but only across standard TCP/IP networks.  2) Application and Runtime Diagnostics - WebLogic Server 12c have diagnostics capabilities embedded on the server called WLDF ("WebLogic Diagnostic Framework") so there is no need to rely on third-part tools. JBoss EAP 6 on the other hand has no diagnostics capabilities. Their only diagnostics tool is the log generated by the application server. Admin people are encouraged to analyse thousands of log lines to find out what is going on. - WebLogic Server 12c complement WLDF with JRockit MC ("Mission Control"), which provides to administrators and developers a complete insight about the JVM performance, behavior and possible bottlenecks. WebLogic Server 12c also have an classloader analysis tool embedded, and even a log analyzer tool that enables administrators and developers to view logs of multiple servers at the same time. JBoss EAP 6 on the other hand relies on third-part tools to do something similar. Again, only log searching are offered to find out whats going on. - WebLogic Server 12c offers end-to-end traceability and monitoring available through Oracle EM ("Enterprise Manager"), including monitoring of business transactions that flows through web servers, ESBs, application servers and database servers, all of this with high deep JVM analysis and diagnostics. JBoss EAP 6 on the other hand, even using JBoss ON ("Operations Network"), which is a separated technology, does not support those features. Red Hat relies on third-part tools to provide direct Oracle database traceability across JVMs. One of those tools are Oracle EM for non-Oracle middleware that manage JBoss, Tomcat, Websphere and IIS transparently. - WebLogic Server 12c with their JRockit support offers a tool called JRockit Flight Recorder, which can give developers a complete visibility of a certain period of application production monitoring with zero extra overhead. This automatic recording allows you to deep analyse threads latency, memory leaks, thread contention, resource utilization, stack overflow damages and GC ("Garbage Collection") cycles, to observe in real time stop-the-world phenomenons, generational, reference count and parallel collects and mutator threads analysis. JBoss EAP 6 don't even dream to support something similar, even because they don't have their own JVM. 3) Application Server Administration - WebLogic Server 12c offers a complete administration console complemented with scripting and macro-like recording capabilities. A single WebLogic console can managed up to hundreds of WebLogic servers belonging to the same domain. JBoss EAP 6 on the other hand has a limited console and provides a XML centric administration. JBoss, after ten years, started the development of a rudimentary centralized administration that still leave a lot of administration tasks aside, so admin people and developers must touch scripts and XML configuration files for most advanced and even simple administration tasks. This lead applications to error prone and risky deployments. Even using JBoss ON, JBoss EAP are not able to offer decent administration features for admin people which must be high skilled in JBoss internal architecture and its managing capabilities. - Oracle EM is available to manage multiple domains, databases, application servers, operating systems and virtualization, with a complete end-to-end visibility. JBoss ON does not provide management capabilities across the complete architecture, only basic monitoring. Even deployment must be done aside JBoss ON which does no integrate well with others softwares than JBoss. Until now, JBoss ON does not supports JBoss EAP 6, so even their minimal support for JBoss are not available for JBoss EAP 6 leaving customers uncovered and subject to high skilled JBoss admin people. - WebLogic Server 12c has the same administration model whatever is the topology selected by the customer. JBoss EAP 6 on the other hand differentiates between two operational models: standalone-mode and domain-mode, that are not consistent with each other. Depending on the mode used, the administration skill is different. - WebLogic Server 12c has no point-of-failures processes, and it does not need to define any specialized server. Domain model in WebLogic is available for years (at least ten years or more) and is production proven. JBoss EAP 6 on the other hand needs special processes to garantee JBoss integrity, the PC ("Process-Controller") and the HC ("Host-Controller"). Different from WebLogic, the domain model in JBoss is quite new (one year at tops) of maturity, and need to mature considerably until start doing things like WebLogic domain model does. - WebLogic Server 12c supports parallel deployment model which enables some artifacts being deployed at the same time. JBoss EAP 6 on the other hand does not have any similar feature. Every deployment are done atomically in the containers. This means that if you have a huge EAR (an EAR of 120 MB of size for instance) and deploy onto JBoss EAP 6, this EAR will take some minutes in order to starting accept thread requests. The same EAR deployed onto WebLogic Server 12c will reduce the deployment time at least in 2X compared to JBoss. 4) Support and Upgrades - WebLogic Server 12c has patch management available. JBoss EAP 6 on the other hand has no patch management available, each JBoss EAP instance should be patched manually. To achieve such feature, you need to buy a separated technology called JBoss ON ("Operations Network") that manage this type of stuff. But until now, JBoss ON does not support JBoss EAP 6 so, in practice, JBoss EAP 6 does not have this feature. - WebLogic Server 12c supports previuous WebLogic domains without any reconfiguration since its kernel is robust and mature since its creation in 1995. JBoss EAP 6 on the other hand has a proven lack of supportability between JBoss AS 4, 5, 6 and 7. Different kernels and messaging engines were implemented in JBoss stack in the last five years reveling their incapacity to create a well architected and proven middleware technology. - WebLogic Server 12c has patch prescription based on customer configuration. JBoss EAP 6 on the other hand has no such capability. People need to create ticket supports and have their installations revised by Red Hat support guys to gain some patch prescription from them. - Oracle WebLogic Server independent of the version has 8 years of support of new patches and has lifetime release of existing patches beyond that. JBoss EAP 6 on the other hand provides patches for a specific application server version up to 5 years after the release date. JBoss EAP 4 and previous versions had only 4 years. A good question that Red Hat will argue to answer is: "what happens when you find issues after year 5"?  5) RAC ("Real Application Clusters") Support - WebLogic Server 12c ships with a specific JDBC driver to leverage Oracle RAC clustering capabilities (Fast-Application-Notification, Transaction Affinity, Fast-Connection-Failover, etc). Oracle JDBC thin driver are also available. JBoss EAP 6 on the other hand ships only the standard Oracle JDBC thin driver. Load balancing with Oracle RAC are not supported. Manual intervention in case of planned or unplanned RAC downtime are necessary. In JBoss EAP 6, situation does not reestablish automatically after downtime. - WebLogic Server 12c has a feature called Active GridLink for Oracle RAC which provides up to 3X performance on OLTP applications. This seamless integration between WebLogic and Oracle database enable more value added to critical business applications leveraging their investments in Oracle database technology and Oracle middleware. JBoss EAP 6 on the other hand has no performance gains at all, even when admin people implement some kind of connection-pooling tuning. - WebLogic Server 12c also supports transaction and web session affinity to the Oracle RAC, which provides aditional gains of performance. This is particularly interesting if you are creating a reliable solution that are distributed not only in an LAN cluster, but into a different data center. JBoss EAP 6 on the other hand has no such support. 6) Standards and Technology Support - WebLogic Server 12c is fully Java EE 6 compatible and production ready since december of 2011. JBoss EAP 6 on the other hand became fully compatible with Java EE 6 only in the community version after three months, and production ready only in a few days considering that this article was written in June of 2012. Red Hat says that they are the masters of innovation and technology proliferation, but compared with Oracle and even other proprietary vendors like IBM, they historically speaking are lazy to deliver the most newest technologies and standards adherence. - Oracle is the steward of Java, driving innovation into the platform from commercial and open-source vendors. Red Hat on the other hand does not have its own JVM and relies on third-part JVMs to complete their application server offer. 95% of Red Hat customers are using Oracle HotSpot as JVM, which means that without Oracle involvement, their support are limited exclusively to the application server layer and we all know that most problems are happens in the JVM layer. - WebLogic Server 12c supports natively JDK 7, which empower developers to explore the maximum of the Java platform productivity when writing code. This feature differentiate WebLogic from others application servers (except GlassFish that are also managed by Oracle) because the usage of JDK 7 introduce such remarkable productivity features like the "try-with-resources" enhancement, catching multiple exceptions with one try block, Strings in the switch statements, JVM improvements in terms of JDBC, I/O, networking, security, concurrency and of course, the most important feature of Java 7: native support for multiple non-Java languages. More features regarding JDK 7 can be found here. JBoss EAP 6 on the other hand does not support JDK 7 officially, they comment in their community version that "Java SE 7 can be used with JBoss 7" which does not gives you any guarantees of enterprise support for JDK 7. - Oracle WebLogic Server 12c supports integration with Spring framework allowing Spring applications to use WebLogic special transaction manager, exposing bean interfaces to WebLogic MBeans to take advantage of all WebLogic monitoring and administration advantages. JBoss EAP 6 on the other hand has no special integration with Spring. In fact, Red Hat offers a suspicious package called "JBoss Web Platform" that in theory supports Spring, but in practice this package does not offers any special integration. It is just a facility for Red Hat customers to have support from both JBoss and Spring technology using the same customer support. 7) Lightweight Development - Oracle WebLogic Server 12c and Oracle GlassFish are completely integrated and can share applications without any modifications. Starting with the 12c version, WebLogic now understands natively GlassFish deployment descriptors and specific configurations in order to offer you a truly and reliable migration path from a community Java EE application server to a enterprise middleware product like WebLogic. JBoss EAP 6 on the other hand has no support to natively reuse an existing (or still in development) application from JBoss AS community server. Users of JBoss suffer of critical issues during deployment time that includes: changing the libraries and dependencies of the application, patching the DTD or XSD deployment descriptors, refactoring of the application layers due classloading issues and anomalies, rebuilding of persistence, business and web layers due issues with "usage of the certified version of an certain dependency" or "frameworks that Red Hat potentially does not recommend" etc. If you have the culture or enterprise IT directive of developing Java EE applications using community middleware to in a certain future, transition to enterprise (supported by a vendor) middleware, Oracle WebLogic plus Oracle GlassFish offers you a more sustainable solution. - WebLogic Server 12c has a very light ZIP distribution (less than 165 MB). JBoss EAP 6 ZIP size is around 130 MB, together with JBoss ON you have more 100 MB resulting in a higher download footprint. This is particularly interesting if you plan to use automated setup of application server instances (for example, to rapidly setup a development or staging environment) using Maven or Hudson. - WebLogic Server 12c has a complete integration with Maven allowing developers to setup WebLogic domains with few commands. Tasks like downloading WebLogic, installation, domain creation, data sources deployment are completely integrated. JBoss EAP 6 on the other hand has a limited offer integration with those tools.  - WebLogic Server 12c has a startup mode called WLX that turns-off EJB, JMS and JCA containers leaving enabled only the web container with Java EE 6 web profile. JBoss EAP 6 on the other hand has no such feature, you need to disable manually the containers that you do not want to use. - WebLogic Server 12c supports fastswap, which enables you to change classes without redeployment. This is particularly interesting if you are developing patches for the application that is already deployed and you do not want to redeploy the entire application. This is the same behavior that most application servers offers to JSP pages, but with WebLogic Server 12c, you have the same feature for Java classes in general. JBoss EAP 6 on the other hand has no such support. Even JBoss EAP 5 does not support this until now. 8) JMS and Messaging - WebLogic Server 12c has a proven and high scalable JMS implementation since its initial release in 1995. JBoss EAP 6 on the other hand has a still immature technology called HornetQ, which was introduced in JBoss EAP 5 replacing everything that was implemented in the previous versions. Red Hat loves to introduce new technologies across JBoss versions, playing around with customers and their investments. And when they are asked about why they have changed the implementation and caused such a mess, their answer is always: "the previous implementation was inadequate and not aligned with the community strategy so we are creating a new a improved one". This Red Hat practice leads to uncomfortable investments that in a near future (sometimes less than a year) will be affected in someway. - WebLogic Server 12c has troubleshooting and monitoring features included on the WebLogic console and WLDF. JBoss EAP 6 on the other hand has no direct monitoring on the console, activity is reflected only on the logs, no debug logs available in case of JMS issues. - WebLogic Server 12c has extremely good performance and scalability. JBoss EAP 6 on the other hand has a JMS storage mechanism relying on Oracle database or MySQL. This means that if an issue in production happens and Red Hat affirms that an performance issue is happening due to database problems, they will not support you on the performance issue. They will orient you to call Oracle instead. - WebLogic Server 12c supports messaging enterprise features like SAF ("Store and Forward"), Distributed Queues/Topics and Foreign JMS providers support that leverage JMS implementations without compromise developer code making things completely transparent. JBoss EAP 6 on the other hand do not even dream to support such features. 9) Caching and Grid - Coherence, which is the leading and most mature data grid technology from Oracle, is available since early 2000 and was integrated with WebLogic in 2009. Coherence and WebLogic clusters can be both managed from WebLogic administrative console. Even Node Manager supports Coherence. JBoss on the other hand discontinued JBoss Cache, which was their caching implementation just like they did with the messaging implementation (JBossMQ) which was a issue for long term customers. JBoss EAP 6 ships InfiniSpan version 1.0 which is immature and lack a proven record of successful cases and reliability. - WebLogic Server 12c has a feature called ActiveCache which uses Coherence to, without any code changes, replicate HTTP sessions from both WebLogic and other application servers like JBoss, Tomcat, Websphere, GlassFish and even Microsoft IIS. JBoss EAP 6 on the other hand does have such support and even when they do in the future, they probably will support only their own application server. - Coherence can be used to manage both L1 and L2 cache levels, providing support to Oracle TopLink and others JPA compliant implementations, even Hibernate. JBoss EAP 6 and Infinispan on the other hand supports only Hibernate. And most important of all: Infinispan does not have any successful case of L1 or L2 caching level support using Hibernate, which lead us to reflect about its viability. 10) Performance - WebLogic Server 12c is certified with Oracle Exalogic Elastic Cloud and can run unchanged applications at this engineered system. This approach can benefit customers from Exalogic optimization's of both kernel and JVM layers to boost performance in terms of 10X for web, OLTP, JMS and grid applications. JBoss EAP 6 on the other hand has no investment on engineered systems: customers do not have the choice to deploy on a Java ultra fast system if their project becomes relevant and performance issues are detected. - WebLogic Server 12c maintains a performance gain across each new release: starting on WebLogic 5.1, the overall performance gain has been close to 4X, which close to a 20% gain release by release. JBoss on the other hand does not provide SPECJAppServer or SPECJEnterprise performance benchmarks. Their so called "performance gains" remains hidden in their customer environments, which lead us to think if it is true or not since we will never get access to those environments. - WebLogic Server 12c has industry performance benchmarks with submissions across platforms and configurations leading SPECJ. Oracle WebLogic leads SPECJAppServer performance in multiple categories, fitting all customer topologies like: dual-node, single-node, multi-node and multi-node with RAC. JBoss... again, does not provide any SPECJAppServer performance benchmarks. - WebLogic Server 12c has a feature called work manager which allows your application to embrace new performance levels based on critical resource utilization of the CPUs usage. Work managers prioritizes work and allocates threads based on an execution model that takes into account administrator-defined parameters and actual run-time performance and throughput. JBoss EAP 6 on the other hand has no compared feature and probably they never will. Not supporting such feature like work managers, JBoss EAP 6 forces admin people and specially developers to uncover performance gains in a intrusive way, rewriting the code and doing performance refactorings. 11) Professional Services Support - WebLogic Server 12c and any other technology sold by Oracle give customers the possibility of hire OCS ("Oracle Consulting Services") to manage critical scenarios, deployment assistance of new applications, high skilled consultancy of architecture, best practices and people allocation together with customer teams. All OCS services are available without any restrictions, having the customer bought software from Oracle or just starting their implementation before any acquisition. JBoss EAP 6 or Red Hat to be more specifically, only offers professional services if you buy subscriptions from them. If you are developing a new critical application for your business and need the help of Red Hat for a serious issue or architecture decision, they will probably say: "OK... I can help you but after you buy subscriptions from me". Red Hat also does not allows their professional services consultants to manage environments that uses community based software. They will probably force you to first buy a subscription, download their "enterprise" version and them, optionally hire their consultants. - Oracle provides you our university to educate your team into our technologies, including of course specialized trainings of WebLogic application server. At any time and location, you can hire Oracle to train your team so you get trustful knowledge according to your specific needs. Certifications for the products are also available if your technical people desire to differentiate themselves as professionals. Red Hat on the other hand have a limited pool of resources to train your team in their technologies. Basically they are selling training and certification for RHEL ("Red Hat Enterprise Linux") but if you demand more specialized training in JBoss middleware, they will probably connect you to some "certified" partner localized training since they are apparently discontinuing their education center, at least here in Brazil. They were not able to reproduce their success with RHEL education to their middleware division since they need first sell the subscriptions to after gives you specialized training. And again, they only offer you specialized training based on their enterprise version (EAP in the case of JBoss) which means that the courses will be a quite outdated. There are reports of developers that took official training's from Red Hat at this year (2012) and in a certain JBoss advanced course, Red Hat supposedly covered JBossMQ as the messaging subsystem, and even the printed material provided was based on JBossMQ since the training was created for JBoss EAP 4.3. 12) Encouraging Transparency without Ulterior Motives - WebLogic Server 12c like any other software from Oracle can be downloaded any time from anywhere, you should only possess an OTN ("Oracle Technology Network") credential and you can download any enterprise software how many times you want. And is not some kind of "trial" version. It is the official binaries that will be running for ever in your data center. Oracle does not encourages the usage of "specific versions" of our software. The binaries you buy from Oracle are the same binaries anyone in the world could download and use for testing and personal education. JBoss EAP 6 on the other hand are not available for download unless you buy a subscription and get access to the Red Hat enterprise repositories. If you need to test, learn or just start creating your application using Red Hat's middleware software, you should download it from the community website. You are not allowed to download the enterprise version that, according to Red Hat are more secure, reliable and robust. But no one of us want to start the development of a software with an unsecured, unreliable and not scalable middleware right? So what you do? You are "invited" by Red Hat to buy subscriptions from them to get access to the "cool" version of the software. - WebLogic Server 12c prices are publicly available in the Oracle website. If you want to know right now how much WebLogic will cost to your organization, just click here and get access to our price list. In the case of WebLogic, check out the "US Oracle Technology Commercial Price List". Oracle also encourages you to get in touch with a sales representative to discuss discounts that would make possible the investment into our technology. But you are not required to do this, only if you are interested in buying our technology or maybe you want to discuss some discount scenarios. JBoss EAP 6 on the other hand does not have its cost publicly available in Red Hat's website or in any other media, at least is not so easy to get such information. The only link you will possibly find in their website is a "Contact a Sales Representative" link. This is not a very good relationship between an customer and an vendor. This is not an example of transparency, mainly when the software are sold as open. In this situations, customers expects to see the software prices publicly available, so they can have the chance to decide, based on the existing features of the software, if the cost is fair or not. Conclusion Oracle WebLogic is the most mature, secure, reliable and scalable Java EE application server of the market, and have a proven record of success around the globe to prove it's majority. Don't lose the chance to discover today how WebLogic could fit your needs and sustain your global IT middleware strategy, no matter if your strategy are completely based on the Cloud or not.

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  • Android - ListView click HOWTO?

    - by teepusink
    Hi, How do I listen to click event on a ListView? This is what I have now ListView list = (ListView)findViewById(R.id.ListView01); ... list.setAdapter(adapter); When I do the following list.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { public void onItemSelected(AdapterView parentView, View childView, int position, long id) { setDetail(position); } public void onNothingSelected(AdapterView parentView) { } }); That doesn't seem to do anything on click. And all those code live within a class that extends Activity. Thanks, Tee

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  • How can a multi-select-list be edited using asp.net mvc?

    - by Anders Juul
    I'd like to edit an object like the one below. I'd like the UsersSelectedList populated with one or more Users from the UsersGrossList. Using the standard edit-views in mvc, I get only strings and booleans (not shown below) mapped. Many of the examples I find on google utilizes early releases of the mvc framework whereas I use the official 1.0 release. Any examples of the view is appreciated. public class NewResultsState { public IList<User> UsersGrossList { get; set; } public IList<User> UsersSelectedList { get; set; } }

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  • LLBLGen - DeleteMulti

    - by Neil
    I have a checkboxlist of categories, during an update, I am trying to delete all the items in list from the associate table, then insert them all (so I don't have to determine if an item already exists in the associate table and only insert newly checked items). Here is the code I have: // First we need to delete the records from ArticleTopicCategory where articleId is the id of the article we are updating List<Guid> categoriesToDelete = new List<Guid>(); foreach (Guid category in this.View.SelectedCategories) { categoriesToDelete.Add(category); } ArticleTopicCategoryCollection articleCategories = new ArticleTopicCategoryCollection(); PredicateExpression filter = new PredicateExpression(ArticleTopicCategoryFields.Id == categoriesToDelete); articleCategories.DeleteMulti(filter); 'categoriesToDelete' holds a valid list of Guid's that need to be deleted, but they are not being deleted. Thanks in advance!

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  • UINavigationBar height

    - by kpower
    In my app I work with an UINavigationController. I've added it to the window (MainWindow.xib, with IB) and simulated on my main view (in IB: Simulated User Elements / Top Bar / Navigation Bar). Navigation bar is displayed, but its height isn't standard. At least in IB it is bigger than in launched app. What's wrong? And how can I restore height to the initial state (as in IB)? P.S.: I know that I can set it directly from code. But this way looks like a "crutch".

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  • Roll up project-level tasks to the project collection portal in TFS2010

    - by adam.mokan
    I have a Project Collection setup in my TFS2010RC deployment. I have two Projects setup under this collection with their own task lists, which are populated with data. I fully expected the tasks from these individual projects to "roll up" and appear in the task list at the Project Collection level, but they do not. The Project Collection task list is empty. Basically, I'm looking to provide a view so a supervisor could see all tasks across projects quickly and easily. I'm sure I could write a reporting services report, but it seems like this is something so basic that it would have been included and it just need to be turned on or something. I'm sure I'm probably missing something really simple here. Thanks.

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  • Segmented Control to change views

    - by Goods
    I have created an up/down arrow segmented control button on the right side of the navigation bar in my detail view. In a table based application, how can I use these up/down arrows to move through cells in the parent table? The apple "NavBar" sample code has an example of this but the controls are not functional. The iBird program has this functionality as well and it is very nice. Download the "iBird 15" program for free. Any thoughts? Thanks!

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  • Strange problem with UIDocumentInteractionController

    - by Tùng Ð?
    I don't know what wrong with this code but everytime when I run the app, after the Menu is shown, the app crash. NSString * path = [[NSBundle mainBundle] pathForResource:@"tung" ofType:@"doc"]; UIDocumentInteractionController *docController = [UIDocumentInteractionController interactionControllerWithURL:[NSURL fileURLWithPath:path]]; docController.delegate = self; //[docController presentPreviewAnimated:YES]; CGRect rect = CGRectMake(0, 0, 300, 300); [docController presentOptionsMenuFromRect:rect inView:self.view animated:YES]; Error I got: * Terminating app due to uncaught exception 'NSGenericException', reason: '-[UIPopoverController dealloc] reached while popover is still visible.' What should I do now ?

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  • iPad popover textfield - resignFirstResponder doesn't dismiss keyboard

    - by mosdev
    I have two text fields email and password. The following code works fine when the fields are presented on a regular view but when they are on a popover, the resignFirstResponder does not work (becomeFirstResponder works). textFieldsShouldReturn was called for both fields. Any idea if I am missing something? Thanks! - (BOOL)textFieldShouldReturn:(UITextField *)theTextField { if (theTextField == email) { [password becomeFirstResponder]; return NO; } [theTextField resignFirstResponder]; return NO; }

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  • "No Source Available" when managed exception occurs - WPF Visual Studio 2010

    - by Sonic Soul
    for some reason, my visual studio 2010 is not loading debug symbols on my own code. i am using a default WPF application solution. with a sample WPF app i am working on, and running in Debug mode. when i go into debug, i can step through my code. BUT when exception happens in my code (i.e. throw new Exception("test")), visual studio gives me the blue blank screen with "No Source Available. No symbols are loaded blah blah.." AND i can actually "view" exception details, where it will tell me the line of code my exception occured on. so it does know what happened.. it seems. it seems to think that PDB files are not loaded. my setup: options Deubg "Enable just my code (managed only)" is checked. application properties : 1 project running in Debug x86

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  • Seamless jQuery Marquee?

    - by Pez Cuckow
    Is it possible to create a 100% seamless marquee in jQuery (or just javascript but jQuery prefered)? I've made a simple marquee that moves left until it is off the screen then simply jumps (when out of view) to the right and starts again. However I would love it to not have the wait. The only way I could think of doing this would be to duplicate the text and put it after the first text, then swap them round again. However I have no idea how to implement this in jQuery. Any ideas?

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  • problem with tabbed interface as mentioned in the article of josh smith

    - by Egi
    hello guys, i ve got a problem with my programm. here is the link: http://dl.dropbox.com/u/2734432/TabbedInterface.7z once u have opened both tabs, u ll start loosing the references to other collections of the current item in the view. that is because these ids are nullable and once you switch over to the other tab they ll become null. my question is why and how can i corrent that behavoir? if you change the int? to int there are no more problem, but i need them to be nullable!

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  • Cleanup vs Dispose(bool) in MVVM-light

    - by Budda
    In the lastest version of MVVM-light (V3 SP1) both "Dispose()" and "Dipose(bool)" methods in ViewModel class are marked Do not use this method anymore, it will be removed in a future version. Use ICleanup.Cleanup() instead Does this mean that IDisposable interface must not be implemented in all ViewModel classes that are derived from GalaSoft.MvvmLight.ViewModelBase (and cleanup must be overrided)? If yes, using can't be used for view-model instances... Probably I didn't understand something... Please clarify... What are the benefits of such cleaning up? Thanks.

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  • Vb.Net web browser control not firing document complete with AJAX web site.

    - by ajl
    The VB.Net desktop app uses the IE browser control to navigate the web. When a normal page loads the document_complete event fires and I can read the resulting page and go from there. The issue I am having is that the page I am driving is written with AJAX, so the document complete event never fires. Furthermore, when you view the source of the page after it loaded a new portion via AJAX, it hasn't change. How are people handling this? What are my options?

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  • Spring - adding BindingResult to newly created model attribute

    - by Max
    My task is - to create a model attribute by given request parameters, to validate it (in same method) and to give it whole to the View. I was given this code: //Create the model attribute by request parameters Promotion promotion = Promotions.get(someRequestParam); //Add the attribute to the model modelMap.addAttribute("promotion", promotion); if (!promotion.validate()) { BindingResult errors = new BeanPropertyBindingResult(promotion, "promotion"); errors.reject("promotion.invalid"); //TODO: This is the part I don't like model.put(BindingResult.MODEL_KEY_PREFIX + "promotion", errors); } This thing sure works, but that part with creating key with MODEL_KEY_PREFIX and attribute name looks very hackish and not a Spring style to me. Is there a way to make the same thing prettier?

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  • WPF Binding Failure performance hit vs Exception

    - by Aran Mulholland
    when we bind to heterogeneous collection of objects, not all objects have the same set of properties. in the output window we get a message like: System.Windows.Data Error: 39 : BindingExpression path error: 'RoundingFactor' property not found on 'object' ''MultiLineTextMarkingScheme' (HashCode=7262386)'. BindingExpression:Path=RoundingFactor;.......... This doesn't appear to be an exception, but we are concerned it has a performance impact. Should we be concerned and create a view model that has all the properties we wish to bind to (and have the properties that dont exist on the underlying element return null) or can we just leave it. This situation often occurs in a grid scenario where there might be large numbers of these binding failures.

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  • Good examples of MVVM Template

    - by jwarzech
    I am currently working with the Microsoft MVVM template and find the lack of detailed examples frustrating. The included ContactBook example shows very little Command handling and the only other example I've found is from an MSDN Magazine article where the concepts are similar but uses a slightly different approach and still lack in any complexity. Are there any decent MVVM examples that at least show basic CRUD operations and dialog/content switching? Everyone's suggestions were really useful and I will start compiling a list of good resources Frameworks/Templates WPF Model-View-ViewModel Toolkit MVVM Light Toolkit Prism Caliburn Cinch Useful Articles Data Validation in .NET 3.5 Using a ViewModel to Provide Meaningful Validation Error Messages Action based ViewModel and Model validation Dialogs Command Bindings in MVVM More than just MVC for WPF MVVM + Mediator Example Application Additional Libraries WPF Disciples' improved Mediator Pattern implementation(I highly recommend this for applications that have more complex navigation)

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  • CodePlex Daily Summary for Thursday, April 01, 2010

    CodePlex Daily Summary for Thursday, April 01, 2010New ProjectsASP.NET Bing Maps: Extensible and easy to use, this is ASP.NET Bing Maps Control. Drag & Drop and is ready to go. You can configure map mode, map style, add a PushPin...Bricks' Bane: Bricks' Bane is a brick breaker game developed using XNA and published on XBox Live Indy Games. Source code includes a C# library useful for game d...cURL for dotnet: Another dotnet binding for libcurl see http://curl.haxx.se for more info about cURL/libcurlCustom Functoid que acessa o banco de dados SQL: Functoid para Biztalk Server 2006 utilizando dados do SQL Server 2005FEI STU Pharmacy e-shop: Elektronicky obchod s liekmi Vytvorte jednoduchú klient-server aplikáciu, ktorá bude realizovať elektronický obchod s liekmi. Moduly: 1. e-shop f...Flavours of Wix: Investigating building DSL's to create installers based on WIXFulcrum: Fulcrum is a code generation framework built on top of the T4 technology in Visual Studio. GreviousAngel: New team projectHabanero Inferno: Habanero Inferno coming soon.Kawo Pounga !: A useless game !!!LetsXNA!!: This is a project created by members of Linked In group Lets XNA!! to build a XNA game and have fun in the process. The goal is to build a simple ...Linq To Naver , Custom Linq Provider for Naver searchengine OpenAPI: <project name>Linq to Naver </project name> <programming language>C#, CSharp</programming language>LocoSync: LocoSync is a file Syncronization/Backup/Archiver program, which is easily extendable. It is easy to add new syncronization methods using C# code.Natural Language Processing: Natural Language ProcessingNop Commerce Azure: Ce projet vous permet de mettre en place rapidement et simplement votre site d'e-commerce en ligne en bénéficiant de tous les avantages de la plate...Nwinsock: Nwinsock is a component for network , Object Transfer, Pocket Compression, Support TCP,UDP Protocol, Thread Base OnTime: OnTime is a simple program from that matching game back in the day just to bring light to programming techniques. It's developed in C#.?OpenGL ES 2.0 Compact Framework Wrapper: OpenGL ES 2.0 wrapper for .NET Compact Framework. Developed on HTC HD 2 device but should run on any Windows Mobile device that has the correct lib...ortaknokta: bu proje: birkaç kişinin bir araya gelip, istedikleri konularda tartışma yapmalarına olanak saglamak icin hazırlanmaya çalışıl maktadır. P-Data: P-Data es una herramienta que permite obtener información procedente de archivos de datos (Data Profiling) a través de consultas SQL, automatizando...PowerAuras: Addon for World of Warcraft - Displays effects on screen at different conditionsPowerShell ToodleDo Module: PowerShell Module for interacting with toodledo.com online To-Do list site. RSS Reader for Windows Phone 7: This RSS Reader application for windows 7Streamlet Containers: This is my implement of STL-style containers, including a dynamic array, a double-linked list and an r-b-tree. Just for practice. Please feel free...Troav: Social encyclopedia built using c# and the Orchard frameworkUmbraco App_Code/Usercontrol Editor: Package for Umbraco to add App_Code and usercontrol editing to the Developer section of the Umbraco administration system. Will support GeSHi editi...Vczh Reactive Programming Library: Reactive programming library provide a stream or state machine view to use .NET eventsWhoIs XML API: The project uses the public WhoIs XML API service (http://www.whoisxmlapi.com/) to obtain detailed details. The project is written in C# and serial...WPF FlowDocument Examples for VS2008 and VS2010: WPF Text Samples (especially FlowDocument) on the various possible effects: sub- and super-script, ruby (a.k.a. furigana), and various others...You are here (for Windows Mobile): This sample shows you how to play a *.wav file on your device with Compact Framework 2.0. There is better support for playing music on Compact F...New Releases( λunula ): Lunula 0.4.0: Changelog Implemented a virtual machine. Implemented a compiler for the virtual machine. Added first-class continuations (call/cc) Removed co...Alter gear SQL index Management: Setup 1.0.1: Changes Test connection - successful message Connection string timeout property added Setup Project added to project source code Possible issu...ASP.NET Bing Maps: ASP.NET Bing Maps 0.1b: Project Description Extensible and easy to use, this is ASP.NET Bing Maps Control. Drag & Drop and is ready to go. You can configure map mode, map ...ASP.NET MVC Validation Library: ASP.NET MVC Validation Library 1.3: Changes since 1.2: - Support remote validation - Support custom server-side validation - The design of validation attribute is improved Note: test...BigDays 2010: HelfenHelfen - v1: PLEASE NOTE: This project is published under the Microsoft Public License (Ms-PL). http://bigdays10.codeplex.com/license IT IS A DEMO SOLUTION FOR...Caps - Manage your collection!: Caps Console 0.1.4.0 Alpha: This is preview release (Alpha quality). This release contains only limited amount of fixes and new features from user point of view. Major focus f...CSharpQuery: Version 1.0: This version is stable. Please report any possible bugs. The next release will include a sample project and index management tools. Until then pl...Custom Functoid que acessa o banco de dados SQL: Custom Functoid SQL Server: Solução do Visual Studio com código fonte e script SQL do functoid em BiztalkDawf: Dual Audio Workflow: Beta 3: Suppose if two good audio events overlap in time with a videoevent of interest. (This can only happen if PluralEyes isn't used on everything). Befo...Dirac codec user interface: Dirac User Interface (checkin 37132): Same as 36795 version, but done with the last source code.DotNetNuke® Blog: 04.00.00 RC 3: PLEASE NOTE: You may upgrade an RC 2 install. But please do not upgrade previous version of the Beta releases - please start from RC 2 or 03.05.0...DotNetNuke® Skinning Extensions: SimpleTitle Skin Object: This is an example skin object that only renders the "page name" if used in a skin and the "module title" if used in a container. No extra spans, c...Fulcrum: Fulcrum v0.9: Initial release of FulcrumHelloTipi Photos Uploader: Version 2010.03.31: De toute petites corrections : - Correction du bouton envoyer - Impossible d'interagir avec l'application quand on uploadkdar: KDAR 0.0.18: KDAR - Kernel Debugger Anti Rootkit - dispacth table's signature bases updated ( many driver's) - scripts refactored - some bug fixedLegend: Legend Libraries: The latest release.Linq To Naver , Custom Linq Provider for Naver searchengine OpenAPI: Linq to Naver: Linq to NaverLive at Education Meta Web-Service: Live at Education Meta Web Service v. 1.0: We're happy to publish final version of Live at Education Meta Web Serivce (LAEMWS). In this release: Huge list of Windows Live ID enabled servic...Live@edu SSO WebPart for MOSS 2007: WebPart 2.0: This release is based on Live@edu Meta Web Service (laemws - http://laemws.codeplex.com). It is highly recomended to use laemws version of webpart,...LocoSync: LocoSync v0.1r2010.03.31 installer: This is the first public release. Unzip and run setup. Or if you have .net 3.5 runtime available download the exetutable and try...Natural Language Processing: test1: testNop Commerce Azure: Nop Commerce Azure: Nop Commerce Full Sources with additionnals Azure Projects.Nwinsock: NWinsock: Nwinsock version 1.0 is hereOpen NFe: DANFe v1.9.8: Correção CSTOpenGL ES 2.0 Compact Framework Wrapper: v0.1 Sources: First rough release. It has a working sample application which renders a triangle with rotation. Don't expect anything great. Just a very early ...patterns & practices - Windows Azure Guidance: Code Drop 3: Second iteration of a-Expense on Azure. This release builds on the previous one and mainly focuses on replacing SQL Azure by Table Storage. We hav...Posh4DNN: Posh4DNN Scripts 2.0: This release greatly increases the speed of installation and incorporates the use of IIS and SQL Server Snap-ins for managing those services. Inst...Process Enactment Tool Framework: PET 1.1: PET Core new intermediate model with arbitrary "clean" relations among objects and several updates of the object fields (see DependencyInterfacesA...Project Tru Tiên: Elements-test V1-fix (v1): Là Elements-test V1 đã được fix các vấn đề sau: - Fix lỗi hiển thị thú cưỡi Hổ Kỳ Lân - Fix hiển thị tab tiếng trung --> sang tiếng việt - Fix hiể...Sentinel - Log Viewer: Sentinel 0.8.1 (nLog support): Build of the 0.8.1 code (svn revision 36823) which included support for both nLog and log4net that has been in SVN for a while but didn't have a bi...sgMotion Animation Library: SgMotion v1.1 (For Sunburn 1.3.1): SgMotion v1.1 (For Sunburn 1.3.1) This release includes both a Windows & Xbox sample. The sample is set to default at Forward rendering, but can e...sTASKedit: sTASKedit 44538 (Developer Alpha): + nearly all fields are viewed in this release for task verification and identifying of unknownsTest Project (ignore): asdf asdf asdf asdf asdf asdf asdf sadf sdf asdf a: ;dlf jkasdf ;lkasjdf ;dlf jkasdf ;lkasjdf ;dlf jkasdf ;lkasjdf ;dlf jkasdf ;lkasjdf ;dlf jkasdf ;lkasjdf ;dlf jkasdf ;lkasjdf ;dlf jkasdf ;lkasjdf ...Test Project (ignore): cdscs: csdcacacTroav: Traov20100331 Source Pre-Alpah: This is some experiements with implementing custom modules with Microsoft's Orchard frame work. This is very preliminary, and subject to change.Weather Report WebControls: WebWeatherReport: 主要文件的源代码WhoIs XML API: Initial Release: Initial ReleaseYou are here (for Windows Mobile): CAB file and Source Code: You can find more Controls and samples for Windows Mobile developers at: http://www.beemobile4.netMost Popular ProjectshmrEngineRawrWBFS ManagerASP.NET Ajax LibraryMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitAJAX Control ToolkitWindows Presentation Foundation (WPF)ASP.NETLiveUpload to FacebookMost Active ProjectsRawrGraffiti CMSBase Class LibrariesjQuery Library for SharePoint Web ServicesBlogEngine.NETMicrosoft Biology FoundationN2 CMSLINQ to TwitterManaged Extensibility FrameworkFarseer Physics Engine

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  • CSS positioning breaks in Safari

    - by user298638
    Hi all, i have a website in which i am trying to position (using CSS) a certain on the page. the is absolutely positioned and is located inside a relatively positioned paernt . on firefox and even IE it looks ok but on Safari, things get messy and it shows 5 pixels lower than it should. i have tried to figure out for days now what is wrong there but cannot seem to see it. you can find an example link to the problematic page here: http://yaronattar.com/index.php?option=com_content&view=article&id=117:the-new-lovers-2010&catid=51:the-new-lovers-2010&Itemid=242 the problematic is the one conaining the "previous/next" navigation at the bottom right corner of the page. anyone sees what is causing the trouble here? thanks

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  • UIScrollView and Cocos2D

    - by Carl
    I have created a UIScrollView in a cocos2d application. I am adding sprites dynamically, over 3 pages. On the first page, touch works perfectly on a sprite, however if I use the scroll view and navigate to the second page, touch does not work quite right... the sprite will respond to the touch when I touch the screen, approximately the amount I have scrolled to the left. If I scroll back to the first page, touch works perfectly for a sprite. Any ideas? I am using the following tutorial: http://getsetgames.com/2009/08/21/cocos2d-and-uiscrollview/ :)

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  • XCode iPhone Programming: Loading a jpg into a UIImageView from URL

    - by Antonio Murgia
    My app has to load an image from a http server and displaying it into an UIImageView How can i do that?? I tried this: NSString *temp = [NSString alloc]; [temp stringwithString:@"http://192.168.1.2x0/pic/LC.jpg"] temp=[(NSString *)CFURLCreateStringByAddingPercentEscapes( nil, (CFStringRef)temp, NULL, NULL, kCFStringEncodingUTF8) autorelease]; NSData *dato = [NSData alloc]; dato=[NSData dataWithContentsOfURL:[NSURL URLWithString:temp]]; pic = [pic initWithImage:[UIImage imageWithData:dato]]; This code is in viewdidload of the view but nothing is displayed! The server is working because i can load xml files from it. but i can't display that image! I need to load the image programmatically because it has to change depending on the parameter passed! Thank you in advance. Antonio

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  • UIImagePicker and Memory Warning Level 1

    - by user262829
    Hello, Whenever I use a UIImagePicker to take a picker in my app, I get the following message in the debug console: Receive memory warning. Level=1 I am using the following code: imagePickerController = [[UIImagePickerController alloc] init]; imagePickerController.delegate = self; imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera; [window addSubview:imagePickerController.view]; imageView = [[UIImageView alloc] initWithFrame:[window bounds]]; imageView.hidden = YES; [window addSubview:imageView]; [window makeKeyAndVisible]; Does anybody have any ideals? I did not notice this error until I started using the GM Seed for SDK4.

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  • Problems with video playback in iPad.

    - by Leg10n
    I'm trying to implement a MPMoviePlayerView but I can't play the video files, I don't have a device yet to try it on, now I'm testing with simulator, I don't know if this is the cause. So far I've been able to present the view and it shows the first frame of the video, but if I click play, it doesn't play I can move the progress bar and it shows the images, but there's no movement, it stays still. Has anyone experienced something like this? The code of my UIViewController goes like this: NSURL *movieURL=[NSURL fileURLWithPath:@"video.mp4"]; MPMoviePlayerViewController *playerView=[[MPMoviePlayerViewController alloc] initWithContentURL:movieURL]; [self presentMoviePlayerViewControllerAnimated:playerView]; As I said, it shows up, I can move the progress bar back and forth, I see a still image, but no movement. Am I missing something here? or is it the simulator? Thank you

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  • Ipad/Iphone UIActionSheet

    - by SteveU
    Hi All, Ive only posted on here a couple of times and people have been very quick and very helpful when responding so thanks. Im trying to use the UIActionsheet element in my Ipad application. But just to confuse matters im using Cocos2d aswell. But here is my problem. If coding the actionsheet with out cocos2d you would use the following code. [actionSheet showInView:self.view]; However because im using cocos2d and there is no views as such the only thing i can think of to reference is the window.. But this is located in the appdelegate class. ive tried [actionSheet showInView:self.Window]; and i get errors any help?

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  • ASP.NET and HTML5 Local Storage

    - by Stephen Walther
    My favorite feature of HTML5, hands-down, is HTML5 local storage (aka DOM storage). By taking advantage of HTML5 local storage, you can dramatically improve the performance of your data-driven ASP.NET applications by caching data in the browser persistently. Think of HTML5 local storage like browser cookies, but much better. Like cookies, local storage is persistent. When you add something to browser local storage, it remains there when the user returns to the website (possibly days or months later). Importantly, unlike the cookie storage limitation of 4KB, you can store up to 10 megabytes in HTML5 local storage. Because HTML5 local storage works with the latest versions of all modern browsers (IE, Firefox, Chrome, Safari), you can start taking advantage of this HTML5 feature in your applications right now. Why use HTML5 Local Storage? I use HTML5 Local Storage in the JavaScript Reference application: http://Superexpert.com/JavaScriptReference The JavaScript Reference application is an HTML5 app that provides an interactive reference for all of the syntax elements of JavaScript (You can read more about the application and download the source code for the application here). When you open the application for the first time, all of the entries are transferred from the server to the browser (all 300+ entries). All of the entries are stored in local storage. When you open the application in the future, only changes are transferred from the server to the browser. The benefit of this approach is that the application performs extremely fast. When you click the details link to view details on a particular entry, the entry details appear instantly because all of the entries are stored on the client machine. When you perform key-up searches, by typing in the filter textbox, matching entries are displayed very quickly because the entries are being filtered on the local machine. This approach can have a dramatic effect on the performance of any interactive data-driven web application. Interacting with data on the client is almost always faster than interacting with the same data on the server. Retrieving Data from the Server In the JavaScript Reference application, I use Microsoft WCF Data Services to expose data to the browser. WCF Data Services generates a REST interface for your data automatically. Here are the steps: Create your database tables in Microsoft SQL Server. For example, I created a database named ReferenceDB and a database table named Entities. Use the Entity Framework to generate your data model. For example, I used the Entity Framework to generate a class named ReferenceDBEntities and a class named Entities. Expose your data through WCF Data Services. I added a WCF Data Service to my project and modified the data service class to look like this:   using System.Data.Services; using System.Data.Services.Common; using System.Web; using JavaScriptReference.Models; namespace JavaScriptReference.Services { [System.ServiceModel.ServiceBehavior(IncludeExceptionDetailInFaults = true)] public class EntryService : DataService<ReferenceDBEntities> { // This method is called only once to initialize service-wide policies. public static void InitializeService(DataServiceConfiguration config) { config.UseVerboseErrors = true; config.SetEntitySetAccessRule("*", EntitySetRights.All); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; } // Define a change interceptor for the Products entity set. [ChangeInterceptor("Entries")] public void OnChangeEntries(Entry entry, UpdateOperations operations) { if (!HttpContext.Current.Request.IsAuthenticated) { throw new DataServiceException("Cannot update reference unless authenticated."); } } } }     The WCF data service is named EntryService. Notice that it derives from DataService<ReferenceEntitites>. Because it derives from DataService<ReferenceEntities>, the data service exposes the contents of the ReferenceEntitiesDB database. In the code above, I defined a ChangeInterceptor to prevent un-authenticated users from making changes to the database. Anyone can retrieve data through the service, but only authenticated users are allowed to make changes. After you expose data through a WCF Data Service, you can use jQuery to retrieve the data by performing an Ajax call. For example, I am using an Ajax call that looks something like this to retrieve the JavaScript entries from the EntryService.svc data service: $.ajax({ dataType: "json", url: “/Services/EntryService.svc/Entries”, success: function (result) { var data = callback(result["d"]); } });     Notice that you must unwrap the data using result[“d”]. After you unwrap the data, you have a JavaScript array of the entries. I’m transferring all 300+ entries from the server to the client when the application is opened for the first time. In other words, I transfer the entire database from the server to the client, once and only once, when the application is opened for the first time. The data is transferred using JSON. Here is a fragment: { "d" : [ { "__metadata": { "uri": "http://superexpert.com/javascriptreference/Services/EntryService.svc/Entries(1)", "type": "ReferenceDBModel.Entry" }, "Id": 1, "Name": "Global", "Browsers": "ff3_6,ie8,ie9,c8,sf5,es3,es5", "Syntax": "object", "ShortDescription": "Contains global variables and functions", "FullDescription": "<p>\nThe Global object is determined by the host environment. In web browsers, the Global object is the same as the windows object.\n</p>\n<p>\nYou can use the keyword <code>this</code> to refer to the Global object when in the global context (outside of any function).\n</p>\n<p>\nThe Global object holds all global variables and functions. For example, the following code demonstrates that the global <code>movieTitle</code> variable refers to the same thing as <code>window.movieTitle</code> and <code>this.movieTitle</code>.\n</p>\n<pre>\nvar movieTitle = \"Star Wars\";\nconsole.log(movieTitle === this.movieTitle); // true\nconsole.log(movieTitle === window.movieTitle); // true\n</pre>\n", "LastUpdated": "634298578273756641", "IsDeleted": false, "OwnerId": null }, { "__metadata": { "uri": "http://superexpert.com/javascriptreference/Services/EntryService.svc/Entries(2)", "type": "ReferenceDBModel.Entry" }, "Id": 2, "Name": "eval(string)", "Browsers": "ff3_6,ie8,ie9,c8,sf5,es3,es5", "Syntax": "function", "ShortDescription": "Evaluates and executes JavaScript code dynamically", "FullDescription": "<p>\nThe following code evaluates and executes the string \"3+5\" at runtime.\n</p>\n<pre>\nvar result = eval(\"3+5\");\nconsole.log(result); // returns 8\n</pre>\n<p>\nYou can rewrite the code above like this:\n</p>\n<pre>\nvar result;\neval(\"result = 3+5\");\nconsole.log(result);\n</pre>", "LastUpdated": "634298580913817644", "IsDeleted": false, "OwnerId": 1 } … ]} I worried about the amount of time that it would take to transfer the records. According to Google Chome, it takes about 5 seconds to retrieve all 300+ records on a broadband connection over the Internet. 5 seconds is a small price to pay to avoid performing any server fetches of the data in the future. And here are the estimated times using different types of connections using Fiddler: Notice that using a modem, it takes 33 seconds to download the database. 33 seconds is a significant chunk of time. So, I would not use the approach of transferring the entire database up front if you expect a significant portion of your website audience to connect to your website with a modem. Adding Data to HTML5 Local Storage After the JavaScript entries are retrieved from the server, the entries are stored in HTML5 local storage. Here’s the reference documentation for HTML5 storage for Internet Explorer: http://msdn.microsoft.com/en-us/library/cc197062(VS.85).aspx You access local storage by accessing the windows.localStorage object in JavaScript. This object contains key/value pairs. For example, you can use the following JavaScript code to add a new item to local storage: <script type="text/javascript"> window.localStorage.setItem("message", "Hello World!"); </script>   You can use the Google Chrome Storage tab in the Developer Tools (hit CTRL-SHIFT I in Chrome) to view items added to local storage: After you add an item to local storage, you can read it at any time in the future by using the window.localStorage.getItem() method: <script type="text/javascript"> window.localStorage.setItem("message", "Hello World!"); </script>   You only can add strings to local storage and not JavaScript objects such as arrays. Therefore, before adding a JavaScript object to local storage, you need to convert it into a JSON string. In the JavaScript Reference application, I use a wrapper around local storage that looks something like this: function Storage() { this.get = function (name) { return JSON.parse(window.localStorage.getItem(name)); }; this.set = function (name, value) { window.localStorage.setItem(name, JSON.stringify(value)); }; this.clear = function () { window.localStorage.clear(); }; }   If you use the wrapper above, then you can add arbitrary JavaScript objects to local storage like this: var store = new Storage(); // Add array to storage var products = [ {name:"Fish", price:2.33}, {name:"Bacon", price:1.33} ]; store.set("products", products); // Retrieve items from storage var products = store.get("products");   Modern browsers support the JSON object natively. If you need the script above to work with older browsers then you should download the JSON2.js library from: https://github.com/douglascrockford/JSON-js The JSON2 library will use the native JSON object if a browser already supports JSON. Merging Server Changes with Browser Local Storage When you first open the JavaScript Reference application, the entire database of JavaScript entries is transferred from the server to the browser. Two items are added to local storage: entries and entriesLastUpdated. The first item contains the entire entries database (a big JSON string of entries). The second item, a timestamp, represents the version of the entries. Whenever you open the JavaScript Reference in the future, the entriesLastUpdated timestamp is passed to the server. Only records that have been deleted, updated, or added since entriesLastUpdated are transferred to the browser. The OData query to get the latest updates looks like this: http://superexpert.com/javascriptreference/Services/EntryService.svc/Entries?$filter=(LastUpdated%20gt%20634301199890494792L) If you remove URL encoding, the query looks like this: http://superexpert.com/javascriptreference/Services/EntryService.svc/Entries?$filter=(LastUpdated gt 634301199890494792L) This query returns only those entries where the value of LastUpdated > 634301199890494792 (the version timestamp). The changes – new JavaScript entries, deleted entries, and updated entries – are merged with the existing entries in local storage. The JavaScript code for performing the merge is contained in the EntriesHelper.js file. The merge() method looks like this:   merge: function (oldEntries, newEntries) { // concat (this performs the add) oldEntries = oldEntries || []; var mergedEntries = oldEntries.concat(newEntries); // sort this.sortByIdThenLastUpdated(mergedEntries); // prune duplicates (this performs the update) mergedEntries = this.pruneDuplicates(mergedEntries); // delete mergedEntries = this.removeIsDeleted(mergedEntries); // Sort this.sortByName(mergedEntries); return mergedEntries; },   The contents of local storage are then updated with the merged entries. I spent several hours writing the merge() method (much longer than I expected). I found two resources to be extremely useful. First, I wrote extensive unit tests for the merge() method. I wrote the unit tests using server-side JavaScript. I describe this approach to writing unit tests in this blog entry. The unit tests are included in the JavaScript Reference source code. Second, I found the following blog entry to be super useful (thanks Nick!): http://nicksnettravels.builttoroam.com/post/2010/08/03/OData-Synchronization-with-WCF-Data-Services.aspx One big challenge that I encountered involved timestamps. I originally tried to store an actual UTC time as the value of the entriesLastUpdated item. I quickly discovered that trying to work with dates in JSON turned out to be a big can of worms that I did not want to open. Next, I tried to use a SQL timestamp column. However, I learned that OData cannot handle the timestamp data type when doing a filter query. Therefore, I ended up using a bigint column in SQL and manually creating the value when a record is updated. I overrode the SaveChanges() method to look something like this: public override int SaveChanges(SaveOptions options) { var changes = this.ObjectStateManager.GetObjectStateEntries( EntityState.Modified | EntityState.Added | EntityState.Deleted); foreach (var change in changes) { var entity = change.Entity as IEntityTracking; if (entity != null) { entity.LastUpdated = DateTime.Now.Ticks; } } return base.SaveChanges(options); }   Notice that I assign Date.Now.Ticks to the entity.LastUpdated property whenever an entry is modified, added, or deleted. Summary After building the JavaScript Reference application, I am convinced that HTML5 local storage can have a dramatic impact on the performance of any data-driven web application. If you are building a web application that involves extensive interaction with data then I recommend that you take advantage of this new feature included in the HTML5 standard.

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