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• Accounts in Work Items after migration to TFS 2010 and to new domain

  - by Clara Oscura

  Lately I’ve been doing some tests on migrating our TFS 2008 installation to TFS 2010, coupled with a machine and domain change. One particular topic that was tricky is user accounts. We installed first a new machine with TFS 2010 and then migrated the projects in the old server. The work items were migrated with the projects. Great, but if I try to edit one of the old work items I cannot save it anymore because some fields contain old user names (ex. OLDDOMAIN\user) which are not known in the new domain (it should be NEWDOMAIN\user). The errors look like this: When I correct the ‘Assigned To’ field value, I get another error regarding another field: Before TFS 2010, we had TFSUsers power tool. It allow you to map an old user name to a new user name. This is not available anymore because WI fields with user accounts are now synchronized with AD display names changes (explained here). The correct way to go about this in TFS 2010 is to use TFSConfig Identities before adding the new domain accounts into the TFS groups (documented here). So, too late for us. I’ve found a (tedious) workaround to change those old account in work items in order to allow people to keep working with them. 1. Install TFS 2010 power tools 2. Export WIT from your project (VS | Tools | Process Editor | Work Item Types). Save the definition, for example: Original_MyProject_Task.xml 3. Copy the xml (NoReadOnly_MyProject_Task.xml) and edit it. From the field definition of ‘Activated By’, ‘Closed By’ and ‘Resolved By’, remove the following:        <WHENNOTCHANGED field="System.State">           <READONLY />         </WHENNOTCHANGED> 4. Import WIT in VS. Choose the new file (NoReadOnly_MyProject_Task.xml) and import it in MyProject 5. Open all tasks in Excel (flat list). Display the following columns: Asssigned To Activated By Closed By Resolved By Change the user accounts to the new ones (I usually sort each column alphabetically to make it easier). 6. Publish. If you get a conflict on a field, tough luck. You will have to manually choose “Local version” for each work item. I told you it was a tedious process. 7. Import original WIT (Original_MyProject_Task.xml) in MyProject. We only changed the WI definition so that we could change some fields. The original definition should be put back. And what about these other fields? Created By Authorized As These fields are not editable by definition (VS | Tools | Process Editor | Work Item Fields Explorer), even if they are not marked as read-only in the WIT. You can leave the old values. It doesn’t seem to matter to TFS. The other four fields are editable by definition, so only the WIT readonly rule prevents us from changing them. Technorati Tags: TFS,Team Foundation Server 2010,Work Item,Domain change

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• SQL SERVER – Last Two Days to Get FREE Book – Joes 2 Pros Certification 70-433

  - by pinaldave

  Earlier this week we announced that we will be giving away FREE SQL Wait Stats book to everybody who will get SQL Server Joes 2 Pros Combo Kit. We had a fantastic response to the contest. We got an overwhelming response to the offer. We knew there would be a great response but we want to honestly say thank you to all of you for making it happen. Rick and I want to make sure that we express our special thanks to all of you who are reading our books. The offer is still on and there are two more days to avail this offer. We want to make sure that everybody who buys our most selling combo kits, we will send our other most popular SQL Wait Stats book. Please read all the details of the offer here. The books are great resources for anyone who wants to learn SQL Server from fundamentals and eventually go on the certification path of 70-433. Exam 70-433 contains following important subject and the book covers the subject of fundamental. If you are taking the exam or not taking the exam – this book is for every SQL Developer to learn the subject from fundamentals.  Create and alter tables. Create and alter views. Create and alter indexes. Create and modify constraints. Implement data types. Implement partitioning solutions. Create and alter stored procedures. Create and alter user-defined functions (UDFs). Create and alter DML triggers. Create and alter DDL triggers. Create and deploy CLR-based objects. Implement error handling. Manage transactions. Query data by using SELECT statements. Modify data by using INSERT, UPDATE, and DELETE statements. Return data by using the OUTPUT clause. Modify data by using MERGE statements. Implement aggregate queries. Combine datasets. INTERSECT, EXCEPT Implement subqueries. Implement CTE (common table expression) queries. Apply ranking functions. Control execution plans. Manage international considerations. Integrate Database Mail. Implement full-text search. Implement scripts by using Windows PowerShell and SQL Server Management Objects (SMOs). Implement Service Broker solutions. Track data changes. Data capture Retrieve relational data as XML. Transform XML data into relational data. Manage XML data. Capture execution plans. Collect output from the Database Engine Tuning Advisor. Collect information from system metadata. Availability of Book USA - Amazon | India - Flipkart | Indiaplaza Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Joes 2 Pros, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Package Version Numbers, why are they so important

  - by Chris W Beal

  One of the design goals of IPS has been to allow people to easily move forward to a supported "Surface" of component. That is to say, when you  # pkg update your system, you get the latest set of components which all work together, based on the packages you already have installed. During development, this has meant simply you update to the latest "build" of the components. (During development, we build everything and publish everything every two weeks). Now we've released Solaris 11 using the IPS technologies, things are a bit more complicated. We need to be able to reflect all the types of Solaris release we are doing. For example Solaris Development builds, Solaris Update builds and "Support Repository Updates" (the replacement for patches) in the version scheme. So simply saying "151" as the build number isn't sufficient to articulate what you are running, or indeed what is available to update to In my previous blog post I talked about creating your own package, and gave an example FMRI of pkg://tools/[email protected],0.5.11-0.0.0 But it's probably more instructive to look at the FMRI of a Solaris package. The package "core-os" contains all the common utilities and daemons you need to use Solaris.  $ pkg info core-os Name: system/core-os Summary: Core Solaris Description: Operating system core utilities, daemons, and configuration files. Category: System/Core State: Installed Publisher: solaris Version: 0.5.11 Build Release: 5.11 Branch: 0.175.0.0.0.2.1 Packaging Date: Wed Oct 19 07:04:57 2011 Size: 25.14 MB FMRI: pkg://solaris/system/[email protected],5.11-0.175.0.0.0.2.1:20111019T070457Z The FMRI is what we will concentrate on here. In this package "solaris" is the publisher. You can use the pkg publisher command to see where the solaris publisher gets it's bits from $ pkg publisher PUBLISHER TYPE STATUS URI solaris origin online http://pkg.oracle.com/solaris/release/ So we can see we get solaris packages from pkg.oracle.com.  The package name is system/core-os. These can be arbitrary length, just to allow you to group similar packages together. Now on the the interesting? bit, the versions, everything after the @ is part of the version. IPS will only upgrade to a "higher" version. [email protected],5.11-0.175.0.0.0.2.1:20111019T070457Z core-os = Package Name0.5.11 = Component - in this case we're saying it's a SunOS 5.11 package, = separator5.11 = Built on version - to indicate what OS version you built the package on- = another separator0.175.0.0.0.2.1 = Branch Version : = yet another separator20111019T070457Z = Time stamp when the package was published So from that we can see the Branch Version seems rather complex. It is necessarily so, to allow us to describe the hierachy of releases we do In this example we see the following 0.175: is known as the trunkid, and is incremented each build of a new release of Solaris. During Solaris 11 this should not change  0: is the Update release for Solaris. 0 for FCS, 1 for update 1 etc 0: is the SRU for Solaris. 0 for FCS, 1 for SRU 1 etc 0: is reserved for future use 2: Build number of the SRU 1: Nightly ID - only important for Solaris developersTake a hypothetical example [email protected],5.11-0.175.1.5.0.4.1:<something> This would be build 4 of SRU 5 of Update 1 of Solaris 11 This is actually documented in a MOS article 1378134.1 Which you can read if you have a support contract.

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• Oracle MAA Part 1: When One Size Does Not Fit All

  - by JoeMeeks

  The good news is that Oracle Maximum Availability Architecture (MAA) best practices combined with Oracle Database 12c (see video) introduce first-in-the-industry database capabilities that truly make unplanned outages and planned maintenance transparent to users. The trouble with such good news is that Oracle’s enthusiasm in evangelizing its latest innovations may leave some to wonder if we’ve lost sight of the fact that not all database applications are created equal. Afterall, many databases don’t have the business requirements for high availability and data protection that require all of Oracle’s ‘stuff’. For many real world applications, a controlled amount of downtime and/or data loss is OK if it saves money and effort. Well, not to worry. Oracle knows that enterprises need solutions that address the full continuum of requirements for data protection and availability. Oracle MAA accomplishes this by defining four HA service level tiers: BRONZE, SILVER, GOLD and PLATINUM. The figure below shows the progression in service levels provided by each tier. Each tier uses a different MAA reference architecture to deploy the optimal set of Oracle HA capabilities that reliably achieve a given service level (SLA) at the lowest cost.  Each tier includes all of the capabilities of the previous tier and builds upon the architecture to handle an expanded fault domain. Bronze is appropriate for databases where simple restart or restore from backup is ‘HA enough’. Bronze is based upon a single instance Oracle Database with MAA best practices that use the many capabilities for data protection and HA included with every Oracle Enterprise Edition license. Oracle-optimized backups using Oracle Recovery Manager (RMAN) provide data protection and are used to restore availability should an outage prevent the database from being able to restart. Silver provides an additional level of HA for databases that require minimal or zero downtime in the event of database instance or server failure as well as many types of planned maintenance. Silver adds clustering technology - either Oracle RAC or RAC One Node. RMAN provides database-optimized backups to protect data and restore availability should an outage prevent the cluster from being able to restart. Gold raises the game substantially for business critical applications that can’t accept vulnerability to single points-of-failure. Gold adds database-aware replication technologies, Active Data Guard and Oracle GoldenGate, which synchronize one or more replicas of the production database to provide real time data protection and availability. Database-aware replication greatly increases HA and data protection beyond what is possible with storage replication technologies. It also reduces cost while improving return on investment by actively utilizing all replicas at all times. Platinum introduces all of the sexy new Oracle Database 12c capabilities that Oracle staff will gush over with great enthusiasm. These capabilities include Application Continuity for reliable replay of in-flight transactions that masks outages from users; Active Data Guard Far Sync for zero data loss protection at any distance; new Oracle GoldenGate enhancements for zero downtime upgrades and migrations; and Global Data Services for automated service management and workload balancing in replicated database environments. Each of these technologies requires additional effort to implement. But they deliver substantial value for your most critical applications where downtime and data loss are not an option. The MAA reference architectures are inherently designed to address conflicting realities. On one hand, not every application has the same objectives for availability and data protection – the Not One Size Fits All title of this blog post. On the other hand, standard infrastructure is an operational requirement and a business necessity in order to reduce complexity and cost. MAA reference architectures address both realities by providing a standard infrastructure optimized for Oracle Database that enables you to dial-in the level of HA appropriate for different service level requirements. This makes it simple to move a database from one HA tier to the next should business requirements change, or from one hardware platform to another – whether it’s your favorite non-Oracle vendor or an Oracle Engineered System. Please stay tuned for additional blog posts in this series that dive into the details of each MAA reference architecture. Meanwhile, more information on Oracle HA solutions and the Maximum Availability Architecture can be found at: Oracle Maximum Availability Architecture - Webcast Maximize Availability with Oracle Database 12c - Technical White Paper

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• Access Control Service: Transitioning between Active and Passive Scenarios

  - by Your DisplayName here!

  As I mentioned in my last post, ACS features a number of ways to transition between protocol and token types. One not so widely known transition is between passive sign ins (browser) and active service consumers. Let’s see how this works. We all know the usual WS-Federation handshake via passive redirect. But ACS also allows driving the sign in process yourself via specially crafted WS-Federation query strings. So you can use the following URL to sign in using LiveID via ACS. ACS will then redirect back to the registered reply URL in your application: GET /login.srf?   wa=wsignin1.0&   wtrealm=https%3a%2f%2faccesscontrol.windows.net%2f&   wreply=https%3a%2f%2fleastprivilege.accesscontrol.windows.net%3a443%2fv2%2fwsfederation&   wp=MBI_FED_SSL&   wctx=pr%3dwsfederation%26rm%3dhttps%253a%252f%252froadie%252facs2rp%252frest%252f The wsfederation bit in the wctx parameter indicates, that the response to the token request will be transmitted back to the relying party via a POST. So far so good – but how can an active client receive that token now? ACS knows an alternative way to send the token request response. Instead of doing the redirect back to the RP, it emits a page that in turn echoes the token response using JavaScript’s window.external.notify. The URL would look like this: GET /login.srf?   wa=wsignin1.0&   wtrealm=https%3a%2f%2faccesscontrol.windows.net%2f&   wreply=https%3a%2f%2fleastprivilege.accesscontrol.windows.net%3a443%2fv2%2fwsfederation&   wp=MBI_FED_SSL&   wctx=pr%3djavascriptnotify%26rm%3dhttps%253a%252f%252froadie%252facs2rp%252frest%252f ACS would then render a page that contains the following script block: <script type="text/javascript">     try{         window.external.Notify('token_response');     }     catch(err){         alert("Error ACS50021: windows.external.Notify is not registered.");     } </script> Whereas token_response is a JSON encoded string with the following format: {   "appliesTo":"...",   "context":null,   "created":123,   "expires":123,   "securityToken":"...",   "tokenType":"..." } OK – so how does this all come together now? As an active client (Silverlight, WPF, WP7, WinForms etc). application, you would host a browser control and use the above URL to trigger the right series of redirects. All the browser controls support one way or the other to register a callback whenever the window.external.notify function is called. This way you get the JSON string from ACS back into the hosting application – and voila you have the security token. When you selected the SWT token format in ACS – you can use that token e.g. for REST services. When you have selected SAML, you can use the token e.g. for SOAP services. In the next post I will show how to retrieve these URLs from ACS and a practical example using WPF.

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• Handling Configuration Changes in Windows Azure Applications

  - by Your DisplayName here!

  While finalizing StarterSTS 1.5, I had a closer look at lifetime and configuration management in Windows Azure. (this is no new information – just some bits and pieces compiled at one single place – plus a bit of reality check) When dealing with lifetime management (and especially configuration changes), there are two mechanisms in Windows Azure – a RoleEntryPoint derived class and a couple of events on the RoleEnvironment class. You can find good documentation about RoleEntryPoint here. The RoleEnvironment class features two events that deal with configuration changes – Changing and Changed. Whenever a configuration change gets pushed out by the fabric controller (either changes in the settings section or the instance count of a role) the Changing event gets fired. The event handler receives an instance of the RoleEnvironmentChangingEventArgs type. This contains a collection of type RoleEnvironmentChange. This in turn is a base class for two other classes that detail the two types of possible configuration changes I mentioned above: RoleEnvironmentConfigurationSettingsChange (configuration settings) and RoleEnvironmentTopologyChange (instance count). The two respective classes contain information about which configuration setting and which role has been changed. Furthermore the Changing event can trigger a role recycle (aka reboot) by setting EventArgs.Cancel to true. So your typical job in the Changing event handler is to figure if your application can handle these configuration changes at runtime, or if you rather want a clean restart. Prior to the SDK 1.3 VS Templates – the following code was generated to reboot if any configuration settings have changed: private void RoleEnvironmentChanging(object sender, RoleEnvironmentChangingEventArgs e) {     // If a configuration setting is changing     if (e.Changes.Any(change => change is RoleEnvironmentConfigurationSettingChange))     {         // Set e.Cancel to true to restart this role instance         e.Cancel = true;     } } This is a little drastic as a default since most applications will work just fine with changed configuration – maybe that’s the reason this code has gone away in the 1.3 SDK templates (more). The Changed event gets fired after the configuration changes have been applied. Again the changes will get passed in just like in the Changing event. But from this point on RoleEnvironment.GetConfigurationSettingValue() will return the new values. You can still decide to recycle if some change was so drastic that you need a restart. You can use RoleEnvironment.RequestRecycle() for that (more). As a rule of thumb: When you always use GetConfigurationSettingValue to read from configuration (and there is no bigger state involved) – you typically don’t need to recycle. In the case of StarterSTS, I had to abstract away the physical configuration system and read the actual configuration (either from web.config or the Azure service configuration) at startup. I then cache the configuration settings in memory. This means I indeed need to take action when configuration changes – so in my case I simply clear the cache, and the new config values get read on the next access to my internal configuration object. No downtime – nice! Gotcha A very natural place to hook up the RoleEnvironment lifetime events is the RoleEntryPoint derived class. But with the move to the full IIS model in 1.3 – the RoleEntryPoint methods get executed in a different AppDomain (even in a different process) – see here.. You might no be able to call into your application code to e.g. clear a cache. Keep that in mind! In this case you need to handle these events from e.g. global.asax.

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• Webcast Q&A: ResCare Solves Content Lifecycle Challenges with Oracle WebCenter

  - by Kellsey Ruppel

  Last week we had the fourth webcast in our WebCenter in Action webcast series, "ResCare Solves Content Lifecycle Challenges with Oracle WebCenter", where customer Joe Lichtefeld from ResCare and Wayne Boerger & Doug Thompson from Oracle Partner TEAM Informatics shared how Oracle WebCenter is powering allowing ResCare to solve content lifecycle challenges, reduce compliance and business risks, and increase adoption of intranet as primary business communication tool In case you missed it, here's a recap of the Q&A.   Joe Lichtefeld, ResCare  Q: Did you run into any issues in the deployment of the platform?A: We experienced very few issues when implementing the content management and search functionalities. There were some challenges in determining the metadata structure. We tried to find a fine balance between having enough fields to provide the functionality needed, but trying to limit the impact to the contributing members.  Q: What has been the biggest benefit your end users have seen?A: The biggest benefit to date is two-fold. Content on the intranet can be maintained by the individual contributors more timely than in our old process of all requests being updated by IT. The other big benefit is the ability to find the most current version of a document instead of relying on emails and phone calls to track down the "current" version. Q: Was there any resistance internally when implementing the solution? If so, how did you overcome that?A: We experienced very little resistance. Most of our community groups were eager to be able to contribute and maintain their information. We had the normal hurdles of training and follow-up training with implementing a new system and process. As our second phase rolled out access to all employees, we have received more positive feedback on the accessibility of information. Wayne Boerger & Doug Thompson, TEAM Informatics Q: Can you integrate multiple repositories with the Google Search Appliance? Yes, the Google Search Appliance is designed to index lots of different repositories, from both public and internal sources. There are included connectors to many repositories, such as SharePoint, databases, file systems, LDAP, and with the TEAM GSA Connector and the Oracle Content Server. And the index for these repositories can be configured into different collections depending on the use cases that each customer has, and really, for each need within a customer environment. Q: How many different filters can you add when the search results are returned? A: Presuming this question is about the filtering on the search results. You can add as many filters as you like and it can be done by collection or any number of other criteria. Most importantly, customers now have the ability to limit the returned content by a set metadata value. Q: With the TEAM Sites Connector, what types of content can you sync? A: There’s really no limit; if it can be checked into the content server, then it is eligible for sync into Sites.  So basically, any digital file that has relevance to a Sites implementation can be checked into the WC Content central repository and then the connector can/will manage it. Q: Using the Connector, are there any limitations around where in Sites that synced content can be used? A: There are no limitations about where it can be used. When setting up your environment to use it, you just need to think through the different destinations on the Sites side that might use the content; that way you’ve got the right information to create the rules needed for the connector. If you missed the webcast, be sure to catch the replay to see a live demonstration of WebCenter in action!  ResCare Solves Content Lifecycle Challenges with Oracle WebCenter from Oracle WebCenter

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• UPOS RFIDScanner data format

  - by Robert Snyder

  A lot of work that I do currently is based in the OPOS/UPOS world. My company has a device that can read 13.56Mhz tags (RFID), Smart Cards, and Mag Stripe cards. Up until somewhat recently I have only been working with RFID for a very specific scenario. That was to read UltraLight C and Desfire cards. These cards were all setup very specifically so that I could take the data read from those cards and force it into a MSR track2 format. The past couple of weeks, however, I have been working on reading RFID credit cards (since I have a Visa card I've been using mine), and Smart Card credit cards. (The visa card I have has both) In learning how to communicate with SmartCard and reading ISO7816 and EMVCO documents I became a little more familiar with how info is stored. But now I have a question regarding UPOS. The RFID data on my Visa is stored (and read) very similar to how the data is stored and read from the Smart Card on my Visa. Cool. Well in the UPOS spec for SmartCardRW the ReadData method returns a byte array. That's cool, I can just return all that data and then parse it as my heart desires. The RFID though has a LinkedList of Tags. Well this makes sense in terms of my Visa card (reminds me of a question I have in regards to SmartCard, but that is for another question) but what about ULC and Desfire, or for that matter any Mifare card. Pages, Files, Purses don't exactly fit the Tag profile. For instance lets just say I read pages 4-12 on my ULC card. Each page I read is 4 bytes long. Does this mean I have 9 tags in my LinkedList? Is my Tag id the page number? Or then how does that translate to Desfire? I open application 123456 and read file 1 and file 2, Do I have 2 tags? and if so what is my tag id? At least with my Visa I think that I have to use the Tag id (ex 5F24 for my expiration date) and value of {0x15, 0x10, 0x31} Part of me says yes..that makes sense. Another part of me says, "well if that is the case then why doesn't SmartCardRW have Tags?" So that is my question. How do I format my data from those different types of media? or is that the job of my Control Object (the application)? Is so how does it know? The only protocols I have are: // Summary: // Enumerates the available predefined RFID tag protocols the device supports. [Flags] public enum RFIDProtocols { EpcClass0 = 1, RFIDSdt0Plus = 2, EpcClass1 = 4, EpcClass1Gen2 = 8, EpcClass2 = 16, Iso14443A = 4096, Iso14443B = 8192, Iso15693 = 12288, Iso180006B = 16384, Other = 16777216, All = 1073741824, } If I use that well all of my cards that I have are all Iso14443A. I use the ATQA and the SAK to know what type of card I really have. There is no RFID property that lets me specify that. So I'm lost.

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• My collection of favourite TFS utilities

  - by Aaron Kowall

  So, you’re in charge of your company or team’s Team Foundation Server.  Wish it was easier to manage, administer, extend?  Well, here are a few utilities that I highly recommend looking at. I’ve recently had need to rebuild my laptop and upgrade my local TFS environment to TFS 2012 Update 1.  This gave me cause to enumerate some of the utilities I like to have on hand. One of the reasons I love to use TFS on projects is that it’s basically a complete ALM toolkit.  Everything from Task Management, Version Control, Build Management, Test Management, Metrics and Reporting are all there ‘in the box’.  However, no matter how complete a product set it, there are always ways to make it better.  Here are a list of utilities and libraries that are pretty generally useful.  this is not intended to be an exhaustive list of TFS extensions but rather a set that I recommend you look at.  There are many more out there that may be applicable in one scenario or another.  This set of tools should work with TFS 2012 or 2010 if you grab the right version. Most of these tools (and more) are available from the Visual Studio Gallery or CodePlex. General TFS Power Tools – This is ‘the’ collection of utilities and extensions delivered by the Product Group.  Highly recommended from here are the Best Practice Analyzer for ensuring your TFS implementation is healthy and the Team Foundation Server Backups to ensure your TFS databases are backed up correctly. TFS Administrators Toolkit – helps make updates to work item types and reports across many team projects.  Also provides visibility of disk usage by finding large files in version control or test attachments to assist in managing storage utilization. Version Control Git-TF - a set of cross-platform, command line tools that facilitate sharing of changes between TFS and Git. These tools allow a developer to use a local Git repository, and configure it to share changes with a TFS server.  Great for all Git lovers who must integrate into a TFS repository. Testing TFS 2012 Tester Power Tool – A utility for bulk copying test cases which assists in an approach for managing test cases across multiple releases.  A little plug that this utility was written and maintained by Anna Russo of Imaginet where I also work. Test Scribe - A documentation power tool designed to construct documents directly from the TFS for test plan and test run artifacts for the purpose of discussion, reporting etc. Reporting Community TFS Report Extensions - a single repository of SQL Server Reporting Services report for Team Foundation 2010 (and above).  Check out the Test Plan Status report by Imaginet’s Steve St. Jean.  Very valuable for your test managers. Builds TFS Build Manager – A great utility if you are build manager over a complex build environment with many TFS build definitions. Community TFS Build Extensions – contains many custom build activities.  Current release binaries are for TFS 2010 but many of the activities can be recompiled for use with TFS 2012. While compiling this list, I was surprised by the number of TFS utilities and extensions I no longer use/need in TFS 2012 because of the great work by the TFS team addressing many gaps since the 2010 release. Are there any utilities you depend on that I’ve missed?  I’d love to hear about them in the comments!

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• Feynman's inbox

  - by user12607414

  Here is Richard Feynman writing on the ease of criticizing theories, and the difficulty of forming them: The problem is not just to say something might be wrong, but to replace it by something — and that is not so easy. As soon as any really definite idea is substituted it becomes almost immediately apparent that it does not work. The second difficulty is that there is an infinite number of possibilities of these simple types. It is something like this. You are sitting working very hard, you have worked for a long time trying to open a safe. Then some Joe comes along who knows nothing about what you are doing, except that you are trying to open the safe. He says ‘Why don’t you try the combination 10:20:30?’ Because you are busy, you have tried a lot of things, maybe you have already tried 10:20:30. Maybe you know already that the middle number is 32 not 20. Maybe you know as a matter of fact that it is a five digit combination… So please do not send me any letters trying to tell me how the thing is going to work. I read them — I always read them to make sure that I have not already thought of what is suggested — but it takes too long to answer them, because they are usually in the class ‘try 10:20:30’. (“Seeking New Laws”, page 161 in The Character of Physical Law.) As a sometime designer (and longtime critic) of widely used computer systems, I have seen similar difficulties appear when anyone undertakes to publicly design a piece of software that may be used by many thousands of customers. (I have been on both sides of the fence, of course.) The design possibilities are endless, but the deep design problems are usually hidden beneath a mass of superfluous detail. The sheer numbers can be daunting. Even if only one customer out of a thousand feels a need to express a passionately held idea, it can take a long time to read all the mail. And it is a fact of life that many of those strong suggestions are only weakly supported by reason or evidence. Opinions are plentiful, but substantive research is time-consuming, and hence rare. A related phenomenon commonly seen with software is bike-shedding, where interlocutors focus on surface details like naming and syntax… or (come to think of it) like lock combinations. On the other hand, software is easier than quantum physics, and the population of people able to make substantial suggestions about software systems is several orders of magnitude bigger than Feynman’s circle of colleagues. My own work would be poorer without contributions — sometimes unsolicited, sometimes passionately urged on me — from the open source community. If a Nobel prize winner thought it was worthwhile to read his mail on the faint chance of learning a good idea, I am certainly not going to throw mine away. (In case anyone is still reading this, and is wondering what provoked a meditation on the quality of one’s inbox contents, I’ll simply point out that the volume has been very high, for many months, on the Lambda-Dev mailing list, where the next version of the Java language is being discussed. Bravo to those of my colleagues who are surfing that wave.) I started this note thinking there was an odd parallel between the life of the physicist and that of a software designer. On second thought, I’ll bet that is the story for anybody who works in public on something requiring special training. (And that would be pretty much anything worth doing.) In any case, Feynman saw it clearly and said it well.

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• The Future of Air Travel: Intelligence and Automation

  - by BobEvans

  Remember those white-knuckle flights through stormy weather where unexpected plunges in altitude result in near-permanent relocations of major internal organs? Perhaps there’s a better way, according to a recent Wall Street Journal article: “Pilots of a Honeywell International Inc. test plane stayed on their initial flight path, relying on the company's latest onboard radar technology to steer through the worst of the weather. The specially outfitted Boeing 757 barely shuddered as it gingerly skirted some of the most ferocious storm cells over Fort Walton Beach and then climbed above the rest in zero visibility.” Or how about the multifaceted check-in process, which might not wreak havoc on liver location but nevertheless makes you wonder if you’ve been trapped in some sort of covert psychological-stress test? Another WSJ article, called “The Self-Service Airport,” says there’s reason for hope there as well: “Airlines are laying the groundwork for the next big step in the airport experience: a trip from the curb to the plane without interacting with a single airline employee. At the airport of the near future, ‘your first interaction could be with a flight attendant,’ said Ben Minicucci, chief operating officer of Alaska Airlines, a unit of Alaska Air Group Inc.” And in the topsy-turvy world of air travel, it’s not just the passengers who’ve been experiencing bumpy rides: the airlines themselves are grappling with a range of challenges—some beyond their control, some not—that make profitability increasingly elusive in spite of heavy demand for their services. A recent piece in The Economist illustrates one of the mega-challenges confronting the airline industry via a striking set of contrasting and very large numbers: while the airlines pay $7 billion per year to third-party computerized reservation services, the airlines themselves earn a collective profit of only $3 billion per year. In that context, the anecdotes above point unmistakably to the future that airlines must pursue if they hope to be able to manage some of the factors outside of their control (e.g., weather) as well as all of those within their control (operating expenses, end-to-end visibility, safety, load optimization, etc.): more intelligence, more automation, more interconnectedness, and more real-time awareness of every facet of their operations. Those moves will benefit both passengers and the air carriers, says the WSJ piece on The Self-Service Airport: “Airlines say the advanced technology will quicken the airport experience for seasoned travelers—shaving a minute or two from the checked-baggage process alone—while freeing airline employees to focus on fliers with questions. ‘It's more about throughput with the resources you have than getting rid of humans,’ said Andrew O'Connor, director of airport solutions at Geneva-based airline IT provider SITA.” Oracle’s attempting to help airlines gain control over these challenges by blending together a range of its technologies into a solution called the Oracle Airline Data Model, which suggests the following steps: • To retain and grow their customer base, airlines need to focus on the customer experience. • To personalize and differentiate the customer experience, airlines need to effectively manage their passenger data. • The Oracle Airline Data Model can help airlines jump-start their customer-experience initiatives by consolidating passenger data into a customer data hub that drives realtime business intelligence and strategic customer insight. • Oracle’s Airline Data Model brings together multiple types of data that can jumpstart your data-warehousing project with rich out-of-the-box functionality. • Oracle’s Intelligent Warehouse for Airlines brings together the powerful capabilities of Oracle Exadata and the Oracle Airline Data Model to give you real-time strategic insights into passenger demand, revenues, sales channels and your flight network. The airline industry aside, the bullet points above offer a broad strategic outline for just about any industry because the customer experience is becoming pre-eminent in each and there is simply no way to deliver world-class customer experiences unless a company can capture, manage, and analyze all of the relevant data in real-time. I’ll leave you with two thoughts from the WSJ article about the new in-flight radar system from Honeywell: first, studies show that a single episode of serious turbulence can wrack up $150,000 in additional costs for an airline—so, it certainly behooves the carriers to gain the intelligence to avoid turbulence as much as possible. And second, it’s back to that top-priority customer-experience thing and the value that ever-increasing levels of intelligence can deliver. As the article says: “In the cabin, reporters watched screens showing the most intense parts of the nearly 10-mile wide storm, which churned some 7,000 feet below, in vibrant red and other colors. The screens also were filled with tiny symbols depicting likely locations of lightning and hail, which can damage planes and wreak havoc on the nerves of white-knuckle flyers.”  (Bob Evans is senior vice-president, communications, for Oracle.)  

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• How should I plan the inheritance structure for my game?

  - by Eric Thoma

  I am trying to write a platform shooter in C++ with a really good class structure for robustness. The game itself is secondary; it is the learning process of writing it that is primary. I am implementing an inheritance tree for all of the objects in my game, but I find myself unsure on some decisions. One specific issue that it bugging me is this: I have an Actor that is simply defined as anything in the game world. Under Actor is Character. Both of these classes are abstract. Under Character is the Philosopher, who is the main character that the user commands. Also under Character is NPC, which uses an AI module with stock routines for friendly, enemy and (maybe) neutral alignments. So under NPC I want to have three subclasses: FriendlyNPC, EnemyNPC and NeutralNPC. These classes are not abstract, and will often be subclassed in order to make different types of NPC's, like Engineer, Scientist and the most evil Programmer. Still, if I want to implement a generic NPC named Kevin, it would nice to be able to put him in without making a new class for him. I could just instantiate a FriendlyNPC and pass some values for the AI machine and for the dialogue; that would be ideal. But what if Kevin is the one benevolent Programmer in the whole world? Now we must make a class for him (but what should it be called?). Now we have a character that should inherit from Programmer (as Kevin has all the same abilities but just uses the friendly AI functions) but also should inherit from FriendlyNPC. Programmer and FriendlyNPC branched away from each other on the inheritance tree, so inheriting from both of them would have conflicts, because some of the same functions have been implemented in different ways on the two of them. 1) Is there a better way to order these classes to avoid these conflicts? Having three subclasses; Friendly, Enemy and Neutral; from each type of NPC; Engineer, Scientist, and Programmer; would amount to a huge number of classes. I would share specific implementation details, but I am writing the game slowly, piece by piece, and so I haven't implemented past Character yet. 2) Is there a place where I can learn these programming paradigms? I am already trying to take advantage of some good design patterns, like MVC architecture and Mediator objects. The whole point of this project is to write something in good style. It is difficult to tell what should become a subclass and what should become a state (i.e. Friendly boolean v. Friendly class). Having many states slows down code with if statements and makes classes long and unwieldy. On the other hand, having a class for everything isn't practical. 3) Are there good rules of thumb or resources to learn more about this? 4) Finally, where does templating come in to this? How should I coordinate templates into my class structure? I have never actually taken advantage of templating honestly, but I hear that it increases modularity, which means good code.

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• Design Pattern for building a Budget

  - by Scott

  So I've looked at the Builder Pattern, Abstract Interfaces, other design patterns, etc. - and I think I'm over thinking the simplicity behind what I'm trying to do, so I'm asking you guys for some help with either recommending a design pattern I should use, or an architecture style I'm not familiar with that fits my task. So I have one model that represents a Budget in my code. At a high level, it looks like this: public class Budget { public int Id { get; set; } public List<MonthlySummary> Months { get; set; } public float SavingsPriority { get; set; } public float DebtPriority { get; set; } public List<Savings> SavingsCollection { get; set; } public UserProjectionParameters UserProjectionParameters { get; set; } public List<Debt> DebtCollection { get; set; } public string Name { get; set; } public List<Expense> Expenses { get; set; } public List<Income> IncomeCollection { get; set; } public bool AutoSave { get; set; } public decimal AutoSaveAmount { get; set; } public FundType AutoSaveType { get; set; } public decimal TotalExcess { get; set; } public decimal AccountMinimum { get; set; } } To go into more detail about some of the properties here shouldn't be necessary, but if you have any questions about those I will fill more out for you guys. Now, I'm trying to create code that builds one of these things based on a set of BudgetBuildParameters that the user will create and supply. There are going to be multiple types of these parameters. For example, on the sites homepage, there will be an example section where you can quickly see what your numbers look like, so they would be a much simpler set of SampleBudgetBuildParameters then say after a user registers and wants to create a fully filled out Budget using much more information in the DebtBudgetBuildParameters. Now a lot of these builds are going to be using similar code for certain tasks, but might want to also check the status of a users DebtCollection when formulating a monthly spending report, where as a Budget that only focuses on savings might not want to. I'd like to reduce code duplication (obviously) as much as possible, but in my head, every way I can think to do this would require using a base BudgetBuilderFactory to return the correct builder to the caller, and then creating say a SimpleBudgetBuilder that inherits from a BudgetBuilder, and put all duplicate code in the BudgetBuilder, and let the SimpleBudgetBuilder handle it's own cases. Problem is, a lot of the unique cases are unique to 2/4 builders, so there will be duplicate code somewhere in there obviously if I did that. Can anyone think of a better way to either explain a solution to this that may or may not be similar to mine, or a completely different pattern or way of thinking here? I really appreciate it.

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• Introducing the Oracle Linux Playground yum repo

  - by wcoekaer

  We just introduced a new yum repository/channel on http://public-yum.oracle.com called the playground channel. What we started doing is the following: When a new stable mainline kernel is released by Linus or GregKH, we internally build RPMs to test it and do some QA work around it to keep track of what's going on with the latest development kernels. It helps us understand how performance moves up or down and if there are issues, we try to help look into them and of course send that stuff back upstream. Many Linux users out there are interested in trying out the latest features but there are some potential barriers to do this. (1) in general, you are looking at an upstream development distribution, which means that everything changes both in userspace(random applications) and kernel. Projects like Fedora are very useful and someone that wants to just see how the entire distribution evolves with all the changes, this is a great way to be current. A drawback here, though, is that if you have applications that are not part of the distribution, there's a lot of manual work involved or they might just not work because the changes are too drastic. The introduction of systemd is a good example. (2) when you look at many of our customers, that are interested in our database products or applications, the starting point of having a supported/certified userspace/distribution, like Oracle Linux, is a much easier way to get your feet wet in seeing what new/future Linux kernel enhancements could do. This is where the playground channel comes into play. When you install Oracle Linux 6 (which anyone can download and use from http://edelivery.oracle.com/linux), grab the latest public yum repository file http://public-yum.oracle.com/public-yum-ol6.repo, put it in /etc/yum.repos.d and enable the playground repo : [ol6_playground_latest] name=Latest mainline stable kernel for Oracle Linux 6 ($basearch) - Unsupported baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/playground/latest/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=1 Now, all you need to do : type yum update and you will be downloading the latest stable kernel which will install cleanly on Oracle Linux 6. Thus you end up with a stable Linux distribution where you can install all your software, and then download the latest stable kernel (at time of writing this is 3.6.7) without having to recompile a kernel, without having to jump through hoops. There is of course a big, very important disclaimer this is NOT for PRODUCTION use. We want to try and help make it easy for people that are interested, from a user perspective, where the Linux kernel is going and make it easy to install and use it and play around with new features. Without having to learn how to compile a kernel and without necessarily having to install a complete new distribution with all the changes top to bottom. So we don't or won't introduce any new userspace changes, this project really is around making it easy to try out the latest upstream Linux kernels in a very easy way on an environment that's stable and you can keep current, since all the latest errata for Oracle Linux 6 are published on the public yum repo as well. So one repository location for all your current changes and the upstream kernels. We hope that this will get more users to try out the latest kernel and report their findings. We are always interested in understanding stability and performance characteristics. As new features are going into the mainline kernel, that could potentially be interesting or useful for various products, we will try to point them out on our blogs and give an example on how something can be used so you can try it out for yourselves. Anyway, I hope people will find this useful and that it will help increase interested in upstream development beyond reading lkml by some of the more non-kernel-developer types.

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• AI to move custom-shaped spaceships (shape affecting movement behaviour)

  - by kaoD

  I'm designing a networked turn based 3D-6DOF space fleet combat strategy game which relies heavily on ship customization. Let me explain the game a bit, since you need to know a bit about it to set the question. What I aim for is the ability to create your own fleet of ships with custom shapes and attached modules (propellers, tractor beams...) which would give advantages and disadvantages to each ship, so you have lots of different fleet distributions. E.g., long ship with two propellers at the side would let the ship spin around that plane easily, bigger ships would move slowly unless you place lots of propellers at the back (therefore spending more "construction" points and energy when moving, and it will only move fast towards that direction.) I plan to balance all the game around this feature. The game would revolve around two phases: orders and combat phase. During the orders phase, you command the different ships. When all players finish the order phase, the combat phase begins and the ship orders get resolved in real-time for some time, then the action pauses and there's a new orders phase. The problem comes when I think about player input. To move a ship, you need to turn on or off different propellers if you want to steer, travel forward, brake, rotate in place... These propellers don't have to work at their whole power, so you can achieve more movement combinations with less propellers. I think this approach is a bit boring. The player doesn't want to fiddle with motors or anything, you just want to MOVE and KILL. The way I intend the player to give orders to these ships is by a destination and a rotation, and then the AI would calculate the correct propeller power to achive that movement and rotation. Propulsion doesn't have to be the same throught the entire turn calculation (after the orders have been given) so it would be cool if the ships reacted as they move, adjusting the power of the propellers for their needs dynamically, but it may be too hard to implement and it's not really needed for the game to work. In both cases, how would that AI decide which propellers to activate for the best (or at least not worst) trajectory to be achieved? I though about some approaches: Learning AI: The ship types would learn about their movement by trial and error, adjusting their behaviour with more uses, and finally becoming "smart". I don't want to get involved THAT far in AI coding, and I think it can be frustrating for the player (even if you can let it learn without playing.) Pre-calculated timestep movement: Upon ship creation, ALL possible movements are calculated for each propeller configuration and power for a given delta-time. Memory intensive, ugly, bad. Pre-calculated trajectories: The same as above but not for each delta-time but the whole trajectory, which would then be fitted as much as possible. Requires a fixed propeller configuration for the whole combat phase and is still memory intensive, ugly and bad. Continuous brute forcing: The AI continously checks ALL possible propeller configurations throughout the entire combat phase, precalculates a few time steps and decides which is the best one based on that. Con: what's good now might not be that good later, and it's too CPU intensive, ugly, and bad too. Single brute forcing: Same as above, but only brute forcing at the beginning of the simulation, so it needs constant propeller configuration throughout the entire combat phase. Coninuous angle check: This is not a full movement method, but maybe a way to discard "stupid" propeller configurations. Given the current propeller's normal vector and the final one, you can approximate the power needed for the propeller based on the angle. You must do this continuously throughout the whole combat phase. I figured this one out recently so I didn't put in too much thought. A priori, it has the "what's good now might not be that good later" drawback too, and it doesn't care about the other propellers which may act together to make a better propelling configuration. I'm really stuck here. Any ideas?

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

  - by Jabba The hut

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

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• Dont Throw Duplicate Exceptions

  In your code, youll sometimes have write code that validates input using a variety of checks.  Assuming you havent embraced AOP and done everything with attributes, its likely that your defensive coding is going to look something like this: public void Foo(SomeClass someArgument) { if(someArgument == null) { throw new InvalidArgumentException("someArgument"); } if(!someArgument.IsValid()) { throw new InvalidArgumentException("someArgument"); }   // Do Real Work } Do you see a problem here?  Heres the deal Exceptions should be meaningful.  They have value at a number of levels: In the code, throwing an exception lets the develop know that there is an unsupported condition here In calling code, different types of exceptions may be handled differently At runtime, logging of exceptions provides a valuable diagnostic tool Its this last reason I want to focus on.  If you find yourself literally throwing the exact exception in more than one location within a given method, stop.  The stack trace for such an exception is likely going to be identical regardless of which path of execution led to the exception being thrown.  When that happens, you or whomever is debugging the problem will have to guess which exception was thrown.  Guessing is a great way to introduce additional problems and/or greatly increase the amount of time require to properly diagnose and correct any bugs related to this behavior. Dont Guess Be Specific When throwing an exception from multiple code paths within the code, be specific.  Virtually ever exception allows a custom message use it and ensure each case is unique.  If the exception might be handled differently by the caller, than consider implementing a new custom exception type.  Also, dont automatically think that you can improve the code by collapsing the if-then logic into a single call with short-circuiting (e.g. if(x == null || !x.IsValid()) ) that will guarantee that you cant easily throw different information into the message as easily as constructing the exception separately in each case. The code above might be refactored like so:   public void Foo(SomeClass someArgument) { if(someArgument == null) { throw new ArgumentNullException("someArgument"); } if(!someArgument.IsValid()) { throw new InvalidArgumentException("someArgument"); }   // Do Real Work } In this case its taking advantage of the fact that there is already an ArgumentNullException in the framework, but if you didnt have an IsValid() method and were doing validation on your own, it might look like this: public void Foo(SomeClass someArgument) { if(someArgument.Quantity < 0) { throw new InvalidArgumentException("someArgument", "Quantity cannot be less than 0. Quantity: " + someArgument.Quantity); } if(someArgument.Quantity > 100) { throw new InvalidArgumentException("someArgument", "SomeArgument.Quantity cannot exceed 100. Quantity: " + someArgument.Quantity); }   // Do Real Work }   Note that in this last example, Im throwing the same exception type in each case, but with different Message values.  Im also making sure to include the value that resulted in the exception, as this can be extremely useful for debugging.  (How many times have you wished NullReferenceException would tell you the name of the variable it was trying to reference?) Dont add work to those who will follow after you to maintain your application (especially since its likely to be you).  Be specific with your exception messages follow DRY when throwing exceptions within a given method by throwing unique exceptions for each interesting case of invalid state. Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• Learn Many Languages

  - by Jeff Foster

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

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• Managing common code on Windows 7 (.NET) and Windows 8 (WinRT)

  - by ryanabr

  Recent announcements regarding Windows Phone 8 and the fact that it will have the WinRT behind it might make some of this less painful but I  discovered the "XmlDocument" object is in a new location in WinRT and is almost the same as it's brother in .NET System.Xml.XmlDocument (.NET) Windows.Data.Xml.Dom.XmlDocument (WinRT) The problem I am trying to solve is how to work with both types in the code that performs the same task on both Windows Phone 7 and Windows 8 platforms. The first thing I did was define my own XmlNode and XmlNodeList classes that wrap the actual Microsoft objects so that by using the "#if" compiler directive either work with the WinRT version of the type, or the .NET version from the calling code easily. public class XmlNode     { #if WIN8         public Windows.Data.Xml.Dom.IXmlNode Node { get; set; }         public XmlNode(Windows.Data.Xml.Dom.IXmlNode xmlNode)         {             Node = xmlNode;         } #endif #if !WIN8 public System.Xml.XmlNode Node { get; set ; } public XmlNode(System.Xml.XmlNode xmlNode)         {             Node = xmlNode;         } #endif     } public class XmlNodeList     { #if WIN8         public Windows.Data.Xml.Dom.XmlNodeList List { get; set; }         public int Count {get {return (int)List.Count;}}         public XmlNodeList(Windows.Data.Xml.Dom.XmlNodeList list)         {             List = list;         } #endif #if !WIN8 public System.Xml.XmlNodeList List { get; set ; } public int Count { get { return List.Count;}} public XmlNodeList(System.Xml.XmlNodeList list)         {             List = list;        } #endif     } From there I can then use my XmlNode and XmlNodeList in the calling code with out having to clutter the code with all of the additional #if switches. The challenge after this was the code that worked directly with the XMLDocument object needed to be seperate on both platforms since the method for populating the XmlDocument object is completly different on both platforms. To solve this issue. I made partial classes, one partial class for .NET and one for WinRT. Both projects have Links to the Partial Class that contains the code that is the same for the majority of the class, and the partial class contains the code that is unique to the version of the XmlDocument. The files with the little arrow in the lower left corner denotes 'linked files' and are shared in multiple projects but only exist in one location in source control. You can see that the _Win7 partial class is included directly in the project since it include code that is only for the .NET platform, where as it's cousin the _Win8 (not pictured above) has all of the code specific to the _Win8 platform. In the _Win7 partial class is this code: public partial class WUndergroundViewModel     { public static WUndergroundData GetWeatherData( double lat, double lng)         { WUndergroundData data = new WUndergroundData();             System.Net. WebClient c = new System.Net. WebClient(); string req = "http://api.wunderground.com/api/xxx/yesterday/conditions/forecast/q/[LAT],[LNG].xml" ;             req = req.Replace( "[LAT]" , lat.ToString());             req = req.Replace( "[LNG]" , lng.ToString()); XmlDocument doc = new XmlDocument();             doc.Load(c.OpenRead(req)); foreach (XmlNode item in doc.SelectNodes("/response/features/feature" ))             { switch (item.Node.InnerText)                 { case "yesterday" :                         ParseForecast( new FishingControls.XmlNodeList (doc.SelectNodes( "/response/forecast/txt_forecast/forecastdays/forecastday" )), new FishingControls.XmlNodeList (doc.SelectNodes( "/response/forecast/simpleforecast/forecastdays/forecastday" )), data); break ; case "conditions" :                         ParseCurrent( new FishingControls.XmlNode (doc.SelectSingleNode("/response/current_observation" )), data); break ; case "forecast" :                         ParseYesterday( new FishingControls.XmlNodeList (doc.SelectNodes( "/response/history/observations/observation" )),data); break ;                 }             } return data;         }     } in _win8 partial class is this code: public partial class WUndergroundViewModel     { public async static Task< WUndergroundData > GetWeatherData(double lat, double lng)         { WUndergroundData data = new WUndergroundData (); HttpClient c = new HttpClient (); string req = "http://api.wunderground.com/api/xxxx/yesterday/conditions/forecast/q/[LAT],[LNG].xml" ;             req = req.Replace( "[LAT]" , lat.ToString());             req = req.Replace( "[LNG]" , lng.ToString()); HttpResponseMessage msg = await c.GetAsync(req); string stream = await msg.Content.ReadAsStringAsync(); XmlDocument doc = new XmlDocument ();             doc.LoadXml(stream, null); foreach ( IXmlNode item in doc.SelectNodes("/response/features/feature" ))             { switch (item.InnerText)                 { case "yesterday" :                         ParseForecast( new FishingControls.XmlNodeList (doc.SelectNodes( "/response/forecast/txt_forecast/forecastdays/forecastday" )), new FishingControls.XmlNodeList (doc.SelectNodes( "/response/forecast/simpleforecast/forecastdays/forecastday" )), data); break; case "conditions" :                         ParseCurrent( new FishingControls.XmlNode (doc.SelectSingleNode("/response/current_observation" )), data); break; case "forecast" :                         ParseYesterday( new FishingControls.XmlNodeList (doc.SelectNodes( "/response/history/observations/observation")), data); break;                 }             } return data;         }     } Summary: This method allows me to have common 'business' code for both platforms that is pretty clean, and I manage the technology differences separately. Thank you tostringtheory for your suggestion, I was considering that approach.

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• Get Ready for Anytime, Anywhere Engagement

  - by Christie Flanagan

  Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Are you ready for 2015?  According to IDC, 2015 is the year when more users are projected to access the internet using mobile devices than with PC’s or other wired devices.  It’s no doubt that mobile devices are a critical means of communication today, and are on track to become increasingly more important in the coming years. However, device formats are so varied that delivering a mobile web experience that will engage site visitors and enhance your brand can be a daunting task. Solutions that empower organizations to easily extend their web presence to the mobile channel, while saving significant time and effort in managing mobile sites, are now essential in our ever connected mobile world. So what are some of the things organizations should look for in such a solution? Mobile device form factors, networks, protocols, and browsers vary widely, and reformatting web content for thousands of different device and software combinations is a prohibitive task. An effective mobile solution can make this process seamless by automatically formatting designated web content for mobile delivery.  By automatically detecting a site visitor’s device configuration, the selected web content can be sized and formatted for optimal display on that particular device. This can save tremendous time involved in building, formatting, and maintaining individual websites or mobile applications for different mobile devices. It’s not enough to simply support the thousands of different mobile device types that are out there. It’s also critical to make it easy for marketers and other business users to manage mobile sites and mobile content. Those responsible for maintaining an organization’s web and mobile experiences need the ability to edit content using rich text editor tools and then preview that content directly in the context of the mobile website and the traditional website, ideally from the same business user interface. Powerful capabilities such as these make managing the web experience for mobile devices easy, even with frequently changing content, across a multitude of different devices. This saves tremendous time involved in building, formatting, and maintaining individual websites or mobile applications for different mobile devices. When content or business needs change, the business user needs only to change site content once, and it is seamlessly deployed to the web and all mobile channels.Geo-location is another critical input to making the online experience engaging and relevant for web visitors who are increasingly mobile. A mobile solution should enable use of device GPS data to deliver location-based content and services to mobile website visitors. Organizations can provide mobile site visitors with location-sensitive search results, location-based offers and recommendations, integration of maps and directions into site content, and much more – all critical for meeting the needs of those on the go.To hear more about how mobile is changing the game, check out our recent webcast with Ted Schadler, Vice President, Principal Analyst, Forrester, where he discussed why mobile is the new face of engagement, or learn more about how to extend your web presence to the mobile channel with Oracle WebCenter Sites and Oracle WebCenter Sites Mobility Server.

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• problem on my site [closed]

  - by ali

  Errors found while checking this document as XHTML How and from where repaired ,please help my hello, I have a problem on my site, was discovered by the program (A1 website analyzer) you can fix my site? Because I really do not know about the programming language, if it please email me and thank you please see this link it http://jigsaw.w3.org/css-validator/validator?uri=http://www.moneybillion.com/#errors Validation Output: 19 Errors Line 193, Column 261: there is no attribute "data-count" …ass="twitter-share-button" data-count="horizontal" data-via="elibeto1199"Twee…? You have used the attribute named above in your document, but the document type you are using does not support that attribute for this element. This error is often caused by incorrect use of the "Strict" document type with a document that uses frames (e.g. you must use the "Transitional" document type to get the "target" attribute), or by using vendor proprietary extensions such as "marginheight" (this is usually fixed by using CSS to achieve the desired effect instead). This error may also result if the element itself is not supported in the document type you are using, as an undefined element will have no supported attributes; in this case, see the element-undefined error message for further information. How to fix: check the spelling and case of the element and attribute, (Remember XHTML is all lower-case) and/or check that they are both allowed in the chosen document type, and/or use CSS instead of this attribute. If you received this error when using the element to incorporate flash media in a Web page, see the FAQ item on valid flash. Line 193, Column 283: there is no attribute "data-via" …ton" data-count="horizontal" data-via="elibeto1199"Tweet This error may also result if the element itself is not supported in the document type you are using, as an undefined element will have no supported attributes; in this case, see the element-undefined error message for further information. How to fix: check the spelling and case of the element and attribute, (Remember XHTML is all lower-case) and/or check that they are both allowed in the chosen document type, and/or use CSS instead of this attribute. If you received this error when using the element to incorporate flash media in a Web page, see the FAQ item on valid flash. Line 193, Column 393: required attribute "type" not specified …ript" src="//platform.twitter.com/widgets.js"var facebook = {? The attribute given above is required for an element that you've used, but you have omitted it. For instance, in most HTML and XHTML document types the "type" attribute is required on the "script" element and the "alt" attribute is required for the "img" element. Typical values for type are type="text/css" for and type="text/javascript" for . Line 194, Column 23: element "data:post.url" undefined url : "",? You have used the element named above in your document, but the document type you are using does not define an element of that name. This error is often caused by: incorrect use of the "Strict" document type with a document that uses frames (e.g. you must use the "Frameset" document type to get the "" element), by using vendor proprietary extensions such as "" or "" (this is usually fixed by using CSS to achieve the desired effect instead). by using upper-case tags in XHTML (in XHTML attributes and elements must be all lower-case). Line 197, Column 62: required attribute "type" not specified src="http://orkut-share.googlecode.com/svn/trunk/facebook.js"?

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• I am trying to figure out the best way to understand how to cache domain objects

  - by Brett Ryan

  I've always done this wrong, I'm sure a lot of others have too, hold a reference via a map and write through to DB etc.. I need to do this right, and I just don't know how to go about it. I know how I want my objects to be cached but not sure on how to achieve it. What complicates things is that I need to do this for a legacy system where the DB can change without notice to my application. So in the context of a web application, let's say I have a WidgetService which has several methods: Widget getWidget(); Collection<Widget> getAllWidgets(); Collection<Widget> getWidgetsByCategory(String categoryCode); Collection<Widget> getWidgetsByContainer(Integer parentContainer); Collection<Widget> getWidgetsByStatus(String status); Given this, I could decide to cache by method signature, i.e. getWidgetsByCategory("AA") would have a single cache entry, or I could cache widgets individually, which would be difficult I believe; OR, a call to any method would then first cache ALL widgets with a call to getAllWidgets() but getAllWidgets() would produce caches that match all the keys for the other method invocations. For example, take the following untested theoretical code. Collection<Widget> getAllWidgets() { Entity entity = cache.get("ALL_WIDGETS"); Collection<Widget> res; if (entity == null) { res = loadCache(); } else { res = (Collection<Widget>) entity.getValue(); } return res } Collection<Widget> loadCache() { // Get widgets from underlying DB Collection<Widget> res = db.getAllWidgets(); cache.put("ALL_WIDGETS", res); Map<String, List<Widget>> byCat = new HashMap<>(); for (Widget w : res) { // cache by different types of method calls, i.e. by category if (!byCat.containsKey(widget.getCategory()) { byCat.put(widget.getCategory(), new ArrayList<Widget>); } byCat.get(widget.getCatgory(), widget); } cacheCategories(byCat); return res; } Collection<Widget> getWidgetsByCategory(String categoryCode) { CategoryCacheKey key = new CategoryCacheKey(categoryCode); Entity ent = cache.get(key); if (entity == null) { loadCache(); } ent = cache.get(key); return ent == null ? Collections.emptyList() : (Collection<Widget>)ent.getValue(); } NOTE: I have not worked with a cache manager, the above code illustrates cache as some object that may hold caches by key/value pairs, though it's not modelled on any specific implementation. Using this I have the benefit of being able to cache all objects in the different ways they will be called with only single objects on the heap, whereas if I were to cache the method call invocation via say Spring It would (I believe) cache multiple copies of the objects. I really wish to try and understand the best ways to cache domain objects before I go down the wrong path and make it harder for myself later. I have read the documentation on the Ehcache website and found various articles of interest, but nothing to give a good solid technique. Since I'm working with an ERP system, some DB calls are very complicated, not that the DB is slow, but the business representation of the domain objects makes it very clumsy, coupled with the fact that there are actually 11 different DB's where information can be contained that this application is consolidating in a single view, this makes caching quite important.

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• Move over DFS and Robocopy, here is SyncToy!

  - by andywe

  Ever since Windows 2000, I have always had the need to replicate data to multiple endpoints with the same content. Until DFS was introduced, the method of thinking was to either manually copy the data location by location, or to batch script it with xcopy and schedule a task. Even though this worked (and still does today), it was cumbersome, and intensive on the network, especially when dealing with larger amounts of data. Then along came robocopy, as an internal tool written by an enterprising programmer at Microsoft. We used it quite a bit, especially when we could not use DFS in the early days. It was received so well, it made it into the public realm. At least now we could have the ability to determine what files had changed and only replicate those. Well, over time there has been evolution of this ideal. DFS is obviously the Windows enterprise class service to do this, along with BrancheCache..however you don’t always need or want the power of DFS, especially when it comes to small datacenter installations, or remote offices. I have specific data sets that are on closed or restricted networks, that either have a security need for this, or are in remote countries where bandwidth is a premium. FOr this, I use the latest evolution for one off replication names Synctoy. Synctoy is from Microsoft, seemingly released in 2009, that wraps a nice GUI around setting up a paired set of folders (remember the mobile briefcase from Windows 98?), and allowing you the choice of synchronization methods. 1 way, or 2 way. Simply create a paired set of folders on the source and destination, choose your options for content, exclude any file types you don’t want to replicate, and click run. Scheduling is even easier. MS has included a wrapper for doing just this so all you enter in your task schedule in the SynToyCMD.exe, a –R as an argument, and the time schedule. No more complicated command lines or scripts.   I find this especially useful when I use MS backup to back up a system volume, but only want subsets of backup information of a data share and ONLY when that dataset has changed. Not relying on full backups and incremental. An example of this is my application installation master share. I back this up with SyncToy because I do not need multiple backup copies..one copy elsewhere suffices to back it up. At home, very useful for your pictures, videos, music, ect..the backup is online and ready to access, not waiting for you to restore a backup file, and no need to institute a domain simply to have DFS.'   Do note there is a risk..if you accidently delete a file and do not catch this before the next sync, then depending on your SyncToy settings, you can indeed lose that file as the destination updates..so due diligence applies. I make it a rule to sync manly one way…I use my master share for making changes, and allow the schedule to follow suit. Any real important file I lock down as read only through file permissions so it cannot be deleted unless I intervene.   Check out the tool and have some fun! http://www.microsoft.com/en-us/download/details.aspx?DisplayLang=en&id=15155

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• Introduction to WebCenter Personalization: &ldquo;The Conductor&rdquo;

  - by Steve Pepper

  There are some new faces in the town of WebCenter with the latest 11g PS3 release.  A new component has introduced itself as "Oracle WebCenter Personalization", a.k.a WCP, to simplify delivery of a personalized experience and content to end users.  This posting reviews one of the primary components within WCP: "The Conductor". The Conductor: This ain't just an ordinary cloud... One of the founding principals behind WebCenter Personalization was to provide an open client-side API that remains independent of the technology invoking it, in addition to independence from the architecture running it.  The Conductor delivers this, and much, much more. The Conductor is the engine behind WebCenter Personalization that allows flow-based documents, called "Scenarios", to be managed and executed on the server-side through a well published and RESTful api.      The Conductor also supports an extensible model for custom provider integration that can be easily invoked within a Scenario to promote seamless integration with existing business assets. Introducing the Scenario Conductor Scenarios are declarative offline-authored documents using the custom Personalization JDeveloper bundle included with WebCenter.  A Scenario contains one (or more) statements that can: Create variables that are scoped to the current execution context Iterate over collections, or loop until a specific condition is met Execute one or more statements when a condition is met Invoke other scenarios that exist within the same namespace Invoke a data provider that integrates with custom applications Once a variable is assigned within the Scenario's execution context, it can be referenced anywhere within the same Scenario using the common Expression Language syntax used in J2EE web containers. Scenarios are then published and tested to the Integrated WebLogic Server domain, or published remotely to other domains running WebCenter Personalization. Various Client-side Models The Conductor server API is built upon RESTful services that support a wide variety of clients able to communicate over HTTP.  The Conductor supports the following client-side models: REST:  Popular browser-based languages can be used to manage and execute Conductor Scenarios.  There are other public methods to retrieve configured provider metadata that can be used by custom applications. The Conductor currently supports XML and JSON for it's API syntax. Java: WebCenter Personalization delivers a robust and light-weight java client with the popular Jersey framework as it's foundation.  It has never been easier to write a remote java client to manage remote RESTful services. Expression Language (EL): Allow the results of Scenario execution to control your user interface or embed personalized content using the session-scoped managed bean.  The EL client can also be used in straight JSP pages with minimal configuration. Extensible Provider Framework The Conductor supports a pluggable provider framework for integrating custom code with Scenario execution.  There are two types of providers supported by the Conductor: Function Provider: Function Providers are simple java annotated classes with static methods that are meant to be served as utilities.  Some common uses would include: object creation or instantiation, data transformation, and the like.  Function Providers can be invoked using the common EL syntax from variable assignments, conditions, and loops. For example:  ${myUtilityClass:doStuff(arg1,arg2))} If you are familiar with EL Functions, Function Providers are based on the same concept. Data Provider: Like Function Providers, Data Providers are annotated java classes, but they must adhere to a much more strict object model.  Data Providers have access to a wealth of Conductor services, such as: Access to namespace-scoped configuration API that can be managed by Oracle Enterprise Manager, Scenario execution context for expression resolution, and more.  Oracle ships with three out-of-the-box data providers that supports integration with: Standardized Content Servers(CMIS),  Federated Profile Properties through the Properties Service, and WebCenter Activity Graph. Useful References If you are looking to immediately get started writing your own application using WebCenter Personalization Services, you will find the following references helpful in getting you on your way: Personalizing WebCenter Applications Authoring Personalized Scenarios in JDeveloper Using Personalization APIs Externally Implementing and Calling Function Providers Implementing and Calling Data Providers

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• Oracle at ARM TechCon

  - by Tori Wieldt

  ARM TechCon is a technical conference for hardware and software engineers, Oct. 30-Nov 1 in Santa Clara, California. Days two and three of the conference will be geared towards systems designers and software developers, those interested in building ARM processor-based modules, boards, and systems. It will cover all of the hardware and software, tools, ranging from low-power design, networking and connectivity, open source software, and security. Oracle is a sponsor of ARM TechCon, and will present three Java sessions and a hands-on-lab:  "Do You Like Coffee with Your Dessert? Java and the Raspberry Pi" - The Raspberry Pi, an ARM-powered single board computer running a full Linux distro off an SD card has caused a huge wave of interest among developers. This session looks at how Java can be used on a device such as this. Using Java SE for embedded devices and a port of JavaFX, the presentation includes a variety of demonstrations of what the Raspberry Pi is capable of. The Raspberry Pi also provides GPIO line access, and the session covers how this can be used from Java applications. Prepare to be amazed at what this tiny board can do. (Angela Caicedo, Java Evangelist) "Modernizing the Explosion of Advanced Microcontrollers with Embedded Java" - This session explains why Oracle Java ME Embedded is the right choice for building small, connected, and intelligent embedded solutions, such as industrial control applications, smart sensing, wireless connectivity, e-health, or general machine-to-machine (M2M) functionality---extending your business to new areas, driving efficiency, and reducing cost. The new Oracle Java ME Embedded product brings the benefits of Java technology to microcontroller platforms. It is a full-featured, complete, compliant software runtime with value-add features targeted to the embedded space and has the ability to interface with additional hardware components, remote manageability, and over-the-air software updates. It is accompanied by a feature-rich set of tools free of charge. (Fareed Suliman, Java Product Manager) "Embedded Java in Smart Energy and Healthcare" - This session covers embedded Java products and technologies that enable smart and connect devices in the Smart Energy and Healthcare/Medical industries. (speaker Kevin Lee) "Java SE Embedded Development on ARM Made Easy" - This Hands-on Lab aims to show that developers already familiar with the Java develop/debug/deploy lifecycle can apply those same skills to develop Java applications, using Java SE Embedded, on embedded devices. (speaker Jim Connors) In the Oracle booth #603, you can see the following demos: Industry Solutions with JavaThis exhibit consists of a number of industry solutions and how they can be powered by Java technology deployed on embedded systems.  Examples in consumer devices, home gateways, mobile health, smart energy, industrial control, and tablets all powered by applications running on the Java platform are shown.  Some of the solutions demonstrate the ability of Java to connect intelligent devices at the edge of the network to the datacenter or the cloud as a total end-to-end platform.Java in M2M with QualcommThis station will exhibit a new M2M solutions platform co-developed by Oracle and Qualcomm that enables wireless communications for embedded smart devices powered by Java, and share the types of industry solutions that are possible.  In addition, a new platform for wearable devices based on the ARM Cortex M3 platform is exhibited.Why Java for Embedded?Demonstration platforms will show how traditional development environments, tools, and Java programming skills can be used to create applications for embedded devices.  The advantages that Java provides because of  the runtime's abstraction of software from hardware, modularity and scalability, security, and application portability and manageability are shared with attendees. Drop by and see why Java is an optimal applications platform for embedded systems.

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