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  • Object model design: collections on classes

    - by Luke Puplett
    Hi all, Consider Train.Passengers, what type would you use for Passengers where passengers are not supposed to be added or removed by the consuming code? I'm using .NET Framework, so this discussion would suit .NET, but it could apply to a number of modern languages/frameworks. In the .NET Framework, the List is not supposed to be publicly exposed. There's Collection and ICollection and guidance, which I tend to agree with, is to return the closest concrete type down the inheritance tree, so that'd be Collection since it is already an ICollection. But Collection has read/write semantics and so possibly it should be a ReadOnlyCollection, but its arguably common sense not to alter the contents of a collection that you don't have intimate knowledge about so is it necessary? And it requires extra work internally and can be a pain with (de)serialization. At the extreme ends I could just return Person[] (since LINQ now provides much of the benefits that previously would have been afforded by a more specified collection) or even build a strongly-typed PersonCollection or ReadOnlyPersonCollection! What do you do? Thanks for your time. Luke

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  • How should I start with Lisp?

    - by Gary Rowe
    I've been programming for years now, working my way through various iterations of Blub (BASIC, Assembler, C, C++, Visual Basic, Java, Ruby in no particular order of "Blub-ness") and I'd like to learn Lisp. However, I have a lot of intertia what with limited time (family, full time job etc) and a comfortable happiness with my current Blub (Java). So my question is this, given that I'm someone who would really like to learn Lisp, what would be the initial steps to get a good result that demonstrates the superiority of Lisp in web development? Maybe I'm missing the point, but that's how I would initially see the application of my Lisp knowledge. I'm thinking "use dialect A, use IDE B, follow instructions on page C, question your sanity after monads using counsellor D". I'd just like to know what people here consider to be an optimal set of values for A, B, C and perhaps D. Also some discussion on the relative merit of learning such a powerful language as opposed to, say, becoming a Rails expert. Just to add some more detail, I'll be developing on MacOS (or a Linux VM) - no Windows based approaches will be necessary, thanks. Notes for those just browsing by I'm going to keep this question open for a while so that I can offer feedback on the suggestions after I've been able to explore them. If you happen to be browsing by and feel you have something to add, please do. I would really welcome your feedback. Interesting links Assuming you're coming at Lisp from a Java background, this set of links will get you started quickly. Using Intellij's La Clojure plugin to integrate Lisp (videocast) Lisp for the Web Online version of Practical Common Lisp (c/o Frank Shearar) Land of Lisp a (+ (+ very quirky) game based) way in but makes it all so straightforward

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  • SQL SERVER – Copy Column Headers from Resultset – SQL in Sixty Seconds #026 – Video

    - by pinaldave
    SQL Server Management Studio returns results in Grid View, Text View and to the file. When we copy results from Grid View to Excel there is a common complaint that the column  header displayed in resultset is not copied to the Excel. I often spend time in performance tuning databases and I run many DMV’s in SSMS to get a quick view of the server. In my case it is almost certain that I need all the time column headers when I copy my data to excel or any other place. SQL Server Management Studio have two different ways to do this. Method 1: Ad-hoc When result is rendered you can right click on the resultset and click on Copy Header. This will copy the headers along with the resultset. Additionally, you can use the shortcut key CTRL+SHIFT+C for coping column headers along with the resultset. Method 2: Option Setting at SSMS level This is SSMS level settings and I kept this option always selected as I often need the column headers when I select the resultset. Go Tools >> Options >> Query Results >> SQL Server >> Results to Grid >> Check the Box “Include column header when copying or saving the results.” Both of the methods are discussed in following SQL in Sixty Seconds Video. Here is the code used in the video. Related Tips in SQL in Sixty Seconds: Copy Column Headers in Query Analyzers in Result Set Getting Columns Headers without Result Data – SET FMTONLY ON If we like your idea we promise to share with you educational material. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Database, Pinal Dave, PostADay, SQL, SQL Authority, SQL in Sixty Seconds, SQL Query, SQL Scripts, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL, Technology, Video

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  • JavaScript local alias pattern

    - by Bertrand Le Roy
    Here’s a little pattern that is fairly common from JavaScript developers but that is not very well known from C# developers or people doing only occasional JavaScript development. In C#, you can use a “using” directive to create aliases of namespaces or bring them to the global scope: namespace Fluent.IO { using System; using System.Collections; using SystemIO = System.IO; In JavaScript, the only scoping construct there is is the function, but it can also be used as a local aliasing device, just like the above using directive: (function($, dv) { $("#foo").doSomething(); var a = new dv("#bar"); })(jQuery, Sys.UI.DataView); This piece of code is making the jQuery object accessible using the $ alias throughout the code that lives inside of the function, without polluting the global scope with another variable. The benefit is even bigger for the dv alias which stands here for Sys.UI.DataView: think of the reduction in file size if you use that one a lot or about how much less you’ll have to type… I’ve taken the habit of putting almost all of my code, even page-specific code, inside one of those closures, not just because it keeps the global scope clean but mostly because of that handy aliasing capability.

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  • Message Passing Interface (MPI)

    So you have installed your cluster and you are done with introductory material on Windows HPC. Now you want to develop an application with the most common programming model: Message Passing Interface.The MPI programming model is a standard with implementations from many vendors. For newbies (like myself!), I have aggregated below links for getting started.Non-Microsoft MPI resources (useful even if you are not on the Windows platform)1. Message Passing Interface on wikipedia. 2. The MPI standard.3. MPICH2 - an MPI implementation.4. Tutorial on MPI by William Gropp.5. MPI patterns presented as a tutorial with sample code. 6. THE official MPI Forum (maintains the standard) including the wiki discussing the MPI future.7. Great MPI tutorial including at the end the MPI Exercise.8. C++ MPI Exercises by John Burkardt.9. Book online: MPI The Complete Reference.MS-MPI10. Windows HPC Server 2008 - Using MS-MPI whitepaper (15 page doc).11. Tracing MPI applications (27 page doc).12. Using Microsoft MPI (TechNet section).13. Windows HPC Server MPI forum (for posting questions). MPI.NET14. MPI.NET Home Page (not owned by Microsoft).15. MPI.NET Tutorial.16. HPC Development using F# using MPI.NET (38 page doc).Next time I'll post resources for the Microsoft Cluster SOA programming model - happy coding... Comments about this post welcome at the original blog.

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  • What are the options for hosting a small Plone site?

    - by Tina Russell
    I’ve developed a portfolio website for myself using Plone 4, and I’m looking for someplace to host it. Most Plone hosting services seem to focus on large, corporate deployments, but I need something that I can afford on a very limited budget and fits a small, single-admin website. My understanding is that my basic options are thus: I can go with a hosting service that specifically provides Plone. I know of WebFaction, but what others exist? Also, I’d have two stipulations for a Plone hosting service: (a) It needs to use Plone 4, for which I’ve developed my site, and (b) it needs to allow me SSH access to a home directory (including the Plone configuration), so that I may use my custom development eggs and such. I could use a VPS hosting service. What are my options here? Again, I need something cheap and scaled to my level. I could use Amazon EC2 or a similar service (please tell me of any) and pay by the tiniest unit of data. I’m a little scared of this because I have no idea how to do a cost-benefit analysis between this and a regular VPS host. The advantage of this approach would be that I only pay for what I use, making it very scalable, but I don’t know how the overall cost would compare to any VPS host under similar circumstances. What factors enter into the cost of Amazon EC2? What can I expect to pay under either option for regular traffic for a new website? Which one is more desirable for when a rush of visitors drive up my bandwidth bill? One last note: I know Plone isn’t common for websites for individuals, but please don’t try to talk me out of it here; that’s a completely different subject. For now, assume I’m sticking with Plone for good. Also, I have seen the Plone hosting services list on Plone.org—it’s twenty pages long, and the first page was nothing but professional Plone consulting services that sometimes offer hosting for business clients. So, that wasn’t much help. Thank you!

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  • ODI - Creating a Repository in a 12c Pluggable Database

    - by David Allan
    To install ODI 11g into an Oracle 12c pluggable database, one way is to connect using a TNS string to the pluggable database service that is executing. For example when I installed my master repository, I used a JDBC URL such as; jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=mydbserver)(PORT=1522)))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=PDBORA12.US.ORACLE.COM)))   I used the above approach rather than the host:port:sid which is a common mechanism many users use to quickly get up and going. Below you can see the repository creation wizard in action, I used the 11g release and simply installed the master and work repository into my pluggable database. Be wise with your repository IDs, I simply used the default, but you should be aware that these are key in larger deployments. The database in 12c has much more tighter control on users and resources, so just getting the user creating with sufficient resource on tablespaces etc in 12c was a little more work. Once you have the repositories up and running, then the fun starts using the 12c features. More to come.

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  • Design pattern for window management in a Java Swing app

    - by Lord Torgamus
    I've just started creating my very first little Java Swing app. When the program opens, it brings up a single, simple window with a label and a couple buttons. Clicking one of those buttons is supposed to wipe out the welcome screen and replace it with a totally different panel. I'm not sure what the best way to create that functionality is. One method would be to pass my JFrame as an argument into... just about every other component, but that feels hacky to me. Or, there's making each panel double as an action listener, but that doesn't seem right, either. Is there a design pattern I should be applying here? "Replace the contents of the main — and only — window" must be a reasonably common operation. A name for the pattern would be enough; I can use Google on my own from there. (I wouldn't say no to a longer explanation, though.)

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  • Meta-licensing of applications

    - by Gene
    I'm currently evaluating license management solutions for our customized and project-based applications, which are supported by a single server in the intranet of the customer. The applications use common functionality provided by the server (session handling, data synchronization, management capabilities, etc) and are installed on mobile devices. We allow our customers to run the applications on X devices and want to check on the server, whether the customer sticks to this limit (based on the sessions). We don't want licensing software to be installed on the devices itself (for example providing X serials to the customer) nor do we want to host an additional server for licensing in the intranet of the customer. If a client connects, our server should load the license for the application running on the client and verify, that there are sessions left. The licensing managers I looked at (12 products so far) focus on the application itself and don't allow me to implement such a floating behavior as described above. For example, this software could easily be used to create a "Standard Edition" or a "Professional Edition" of our server software, which is not our intention. In XHEO DeployLX there is a "Session Limit", which allows to limit the license to the currently established sessions in ASP.NET, which comes very close to my needs. I'm currently thinking of implementing a custom solution, which allows me to load and enforce custom-defined licenses per application on the server-side and a simple editor to define such licenses (which would contain a type and the limit itself), but I would appreciate an existing, easy to integrate commercial solution. I think it could be possible to use DeployLX for this task, but I would spend a lot of money for implementing most of the solution myself (except for the editor). Thanks in advance for any suggestions or hints. Gene

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  • SQL SERVER – Database in RESTORING State for Long Time

    - by Pinal Dave
    A very interesting question I received the other day. “Our database has been in restoring stage for a long time. We have already restored all the necessary files there. After restoring the files we are expecting that  the database will be in operational mode, however, it is continuously in the restoring mode. Any suggestion?” The question is very common. I sent user follow up emails to understand what is actually going on with the user. I realized after restoring their bak files and log files their database was in the restoring state because they had not restored the latest log file with RECOVERY options. As they had completed all the database restore sequence (bak and log in order), the real need for them was to recover the database from norecovery state. User can restore log files till the database is no recovery mode. If the database is recovered it will be in operation and it can continue database operation. If the database has another operations we cannot restore further log as the chain of the log file after the database is recovered is meaningless. This is the reason why the database has to be norecovery state when it is restored. There are three different ways to recover the database. 1) Recover the database manually with following command. RESTORE DATABASE database_name WITH RECOVERY 2) Recover the database with the last log file. RESTORE LOG database_name FROM backup_device WITH RECOVERY 3) Recover the database when bak is restored RESTORE DATABASE database_name FROM backup_device WITH RECOVERY To understand how the backup restores timeline works read Backup Timeline and Understanding of Database Restore Process in Full Recovery Model. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Backup and Restore, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • EclipseCon 2011

    - by Marcus Hirt
    I sadly could not make it to EclipseCon last year. It was sad for so many reasons, not the least being that Sweden during that part of the year is cold and dark. ;) This year, however, I will be contributing two talks: ---> HotRockit – What to Expect from Oracle’s Converged JVM Oracle is converging the HotSpot and JRockit JVMs to produce a "best of breed JVM". Internally the project is sometimes referred to as the HotRockit project. There is already a large influx of ideas and solutions provided by the JRockit JVM into the Open JDK. Examples of improvements include: Better monitoring and profiling Improved performance Better ergonomics This talk will discuss what to expect from the converged JVM over the next two years, and how this will benefit the Eclipse community. Production-time Problem Solving in Eclipse This session will look at some common problems and pitfalls in Java applications. The focus will be on non-invasive profiling and diagnostics of running production systems. Problems tackled will be: Excessive GC Finding hotspots and optimizing them Optimizing the choice of data structures Synchronization problems Finding out where exceptions are thrown Finding memory leaks All problems will be demonstrated and solved running both the bad-behaving applications and the tools to analyze them from within the Eclipse Java IDE. <--- I hope to meet you there!

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  • Problem installing g++ ccompiler on Ubuntu 14.04

    - by Yash Agarwal
    I tried to install g++ using packages from another user. offline..but there were errors. After connecting to the net I tried to install using sudo apt-get install g++, but it gave the following output: gstreamer0.10-alsa is already the newest version. qtdeclarative5-ubuntu-ui-extras-browser-plugin is already the newest version. python-gconf is already the newest version. gstreamer0.10-tools is already the newest version. libglib2.0-0 is already the newest version. gir1.2-peas-1.0 is already the newest version. libatk-bridge2.0-0 is already the newest version. gnome-session-bin is already the newest version. libgomp1 is already the newest version. libmessaging-menu0 is already the newest version. usb-creator-gtk is already the newest version. libgnome-desktop-3-7 is already the newest version. software-properties-gtk is already the newest version. gnome-control-center-shared-data is already the newest version. unity-scope-gourmet is already the newest version. libcupsimage2 is already the newest version. growisofs is already the newest version. libjson-glib-1.0-common is already the newest version. activity-log-manager is already the newest version. libio-string-perl is already the newest version. qtdeclarative5-qtfeedback-plugin is already the newest version. gnome-power-manager is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. and many more lines like this....but g++ is still not installed

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  • A Primer on Migrating Oracle Applications to a New Platform

    - by Nick Quarmby
    In Support we field a lot of questions about the migration of Oracle Applications to different platforms.  This article describes the techniques available for migrating an Oracle Applications environment to a new platform and discusses some of the common questions that arise during migration.  This subject has been frequently discussed in previous blog articles but there still seems to be a gap regarding the type of questions we are frequently asked in Service Requests. Some of the questions we see are quite abstract. Customers simply want to get a grip on understanding how they approach a migration. Others want to know if a particular architecture is viable. Other customers ask about mixing different platforms within a single Oracle Applications environment.    Just to clarify, throughout this article, the term 'platform' refers specifically to operating systems and not to the underlying hardware. For a clear definition of 'platform' in the context of Oracle Applications Support then Terri's very timely article:Oracle E-Business Suite Platform SmörgåsbordThe migration process is very similar for both 11i and R12 so this article only mentions specific differences where relevant.

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  • Windows Azure Upgrade Domain

    - by kaleidoscope
    Windows Azure automatically divides your role instances into some “logical” domains called upgrade domains. During upgrade, Azure is updating these domains one by one. This is a by design behavior to avoid nasty situations. Some of the last feature additions and enhancements on the platform was the ability to notify your role instances in case of “environment” changes, like adding or removing being most common. In such case, all your roles get a notification of this change. Imagine if you had 50 or 60 role instances, getting notified all at once and start doing various actions to react to this change. It will be a complete disaster for your service. The way to address this problem is upgrade domains. During upgrade Windows Azure updates them one by one and only the associated role instances to a specific domain get notified of the changes taking place. Only a small number of your role instances will get notified, react and the rest will remain intact providing a seamless upgrade experience and no service disruption or downtime. http://www.kefalidis.me/archive/2009/11/27/windows-azure-ndash-what-is-an-upgrade-domain.aspx   Lokesh, M

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  • What, if anything, to do about bow-shaped burndowns?

    - by Karl Bielefeldt
    I've started to notice a recurring pattern to our team's burndown charts, which I call a "bowstring" pattern. The ideal line is the "string" and the actual line starts out relatively flat, then curves down to meet the target like a bow. My theory on why they look like this is that toward the beginning of the story, we are doing a lot of debugging or exploratory work that is difficult to estimate remaining work for. Sometimes it even goes up a little as we discover a task is more difficult once we get into it. Then we get into implementation and test which is more predictable, hence the curving down graph. Note I'm not talking about a big scale like BDUF, just the natural short-term constraint that you have to find the bug before you can fix it, coupled with the fact that stories are most likely to start toward the beginning of a two-week iteration. Is this a common occurrence among scrum teams? Do people see it as a problem? If so, what is the root cause and some techniques to deal with it?

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  • Silverlight Cream for April 12, 2010 -- #837

    - by Dave Campbell
    In this Issue: Michael Washington, Joe McBride, Kirupa, Maurice de Beijer, Brad Abrams, Phil Middlemiss, and CorrinaB. Shoutout: Charlie Kindel has a post up about the incompatibility between VS2010RTM and what we currently have for WP7: Visual Studio 2010 RTM and the Windows Phone Developer Tools CTP and if you want to be notified when that changes, submit your email here. Erik Mork and Co. have their latest This Week in Silverlight 4.9.2010 posted. From SilverlightCream.com: Simplified MVVM: Silverlight Video Player Michael Washington created a 'designable' video player using MVVM that allows any set of controls to implement the player. Great tutorial and all the code. Windows Phone 7 Panorama Behaviors Joe McBride posted a link to a couple WP7 gesture behaviors and a link out to some more by smartyP. Event Bubbling and Tunneling Kirupa has a great article up on Event Bubbling and Tunneling... showing the route that events take through your WPF or Silverlight app. Using dynamic objects in Silverlight 4 Maurice de Beijer has a blog up about binding to indexed properties in Silverlight 4... in other words, you don't have to know what you're binging to at design time. Silverlight 4 + RIA Services - Ready for Business: Ajax Endpoint Brad Abrams is still continuing his RIA series. His latest is on exposing your RIA Services in JSON. Changing Data-Templates at run-time from the VM Looks like I missed Phil Middlemiss' latest post on Changing DataTemplates at run-time. He has a visual of why you might need this right up-front, and is a very common issue. Check out the solution he provides us. Windows System Color Theme for Silverlight - Part Three CorrinaB blogged screenshots and discussion of 3 new themes that are going to be coming up, and what they've done to the controls in general. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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  • Ubuntu Studio Audio Issue with Alsa - No sound

    - by ddragon
    Spec: OS: Ubuntu Studio 13.10 64bit CPU: AMD FX 4100 Quad Core Memory: 6GB DDR3 Video: Radeon HD 4250 (embedded on the mobo) Sound: Delta 66 PCI Issue: I just installed Ubuntu Studio and found out that the streaming audio on a few common website such as Youtube had no sound, and also my CD/DVDs via a player. Thus, in the terminal, I entered: sudo alsa force-reload It actually worked but the sound/audio output was MONO and NOT Stereo (the sources are set to stereo stereo), and it seemed I was not able to locate any settings that can switch the output sound to stereo at all. I went through many forums and eventually "autoremove" pulseaudio since many said I would not be able to utilize both pulseaudio and alsa in this case. Now, I have no audio whatsoever. Does this version of Ubuntu only offer mono sound/audio no matter what I do? Then, I may just need to ditch the whole thing and go back to Windows, which I don't want to since Ubuntu Studio offers many great apps, soundfonts etc.. I have also installed restricted extra, but even after rebooting, it did not resolve the issue. In the terminal mode, I pulled "alsamixer" and unmuted almost everything. But still no sound after a reboot. Just an FYI, I have no saved data under this version of Ubuntu Studio yet, so please feel free to let me know whether I need to install Studio 12.10 instead or mess with some installing/uninstalling apps/plug-ins, etc... If it breaks at some point, all I need to do is to re-install it, which I do not mind at all. Or, if you can provide me a step by step instruction to get this work, I do not mind clean install the Studio 13.10 then wait for your instruction AT ALL!

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  • DevDays ‘00 The Netherlands day #2

    - by erwin21
    Day 2 of DevDays 2010 and again 5 interesting sessions at the World Forum in The Hague. The first session of the today in the big world forum theater was from Scott Hanselman, he gives a lap around .NET 4.0. In his way of presenting he talked about all kind of new features of .NET 4.0 like MEF, threading, parallel processing, changes and additions to the CLR and DLR, WPF and all new language features of .NET 4.0. After a small break it was ready for session 2 from Scott Allen about Tips, Tricks and Optimizations of LINQ. He talked about lazy and deferred executions, the difference between IQueryable and IEnumerable and the two flavors of LINQ syntax. The lunch was again very good prepared and delicious, but after that it was time for session 3 Web Vulnerabilities and Exploits from Alex Thissen. This was no normal session but more like a workshop, we decided what kind of subjects we discussed, the subjects where OWASP, XSS and other injections, validation, encoding. He gave some handy tips and tricks how to prevent such attacks. Session 4 was about the new features of C# 4.0 from Alex van Beek. He talked about Optional- en Named Parameters, Generic Co- en Contra Variance, Dynamic keyword and COM Interop features. He showed how to use them but also when not to use them. The last session of today and also the last session of DevDays 2010 was about WCF Best Practices from Gerben van Loon. He talked about 7 best practices that you must know when you are going to use WCF. With some quick demos he showed the problem and the solution for some common issues. It where two interesting days and next year i sure will be attending again.

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  • Creating the concept of Time

    - by Jamie Dixon
    So I've reached the point in my exploration of gaming where I'd like to impliment the concept of time into my little demo I've been building. What are some common methodologies for creating the concept of time passing within a game? My thoughts so far: My game loop tendes to spend a fair bit of time sitting around waiting or user input so any time system will likely need to be run in a seperate thread. What I've currently done is create a BackgroundWorker passing in a method that contains a loop triggering every second. This is working fine and I can output information to the console from here etc. Inside this loop I have a DateTime object that is incrimented by 1 minute for every realtime second. (the game begins in the year 01/01/01) Is this a standard way of acheiving this result or are there more tried and tested methods? I'm also curious about how to go about performing time based actions (reducing player energy, moving entities around the game board, life/death etc). Thanks for any pointers or advice. I've searched around however I'm not familiar enough with the terms and so my searches are yeilding little result on this one.

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  • Learning advanced java skills

    - by moe
    I've been programming in java for a while and I really like the language, I've mostly just done game programming, but I want to get a feel for some of the more commonly used api's and frameworks and just get a generally more well-rounded grasp of the language and the common libraries in the current job market. From what I found things like spring, hibernate, and GWT are pretty in demand right now. I looked at some tutorials online and they weren't hard to follow but I really felt like I had no context for what I was learning - I had no idea how any of it would be use in a real work environment. I know nothing can rival the benefit I'd get from actual work experience but that's not an option for me right now, I need another way to learn these technologies in a way where I'll at least feel comfortable working with them and know what I'm doing beyond just understanding what code does what. I checked out a few books but they were all really old(like pre-2006, am I right to assume those books would be kind of out of date today?) or required experience with libraries that I didn't have and can't get. I hate getting stuck looking for the best resource to learn something instead of spending my time actually learning. All I really want is someone to point me to a resource(website or ebook) that is aimed at already experienced java developers and will not only teach me some interesting useful java technology(anything that is useful, I dont know much outside of graphics libraries and game related things so I was thinking some database or web programming api's) but also give me a good perspective of it and leave me feeling confident that I could actually use what I learned on a practical application. If my post makes you think I'm not yet experienced to be learning these things, which I doubted earlier today but am now starting to question, then what do you think is the next step for me? I just want to get better at java. Thanks everyone

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  • How to tell if SPARC T4 crypto is being used?

    - by danx
    A question that often comes up when running applications on SPARC T4 systems is "How can I tell if hardware crypto accleration is being used?" To review, the SPARC T4 processor includes a crypto unit that supports several crypto instructions. For hardware crypto these include 11 AES instructions, 4 xmul* instructions (for AES GCM carryless multiply), mont for Montgomery multiply (optimizes RSA and DSA), and 5 des_* instructions (for DES3). For hardware hash algorithm optimization, the T4 has the md5, sha1, sha256, and sha512 instructions (the last two are used for SHA-224 an SHA-384). First off, it's easy to tell if the processor T4 crypto instructions—use the isainfo -v command and look for "sparcv9" and "aes" (and other hash and crypto algorithms) in the output: $ isainfo -v 64-bit sparcv9 applications crc32c cbcond pause mont mpmul sha512 sha256 sha1 md5 camellia kasumi des aes ima hpc vis3 fmaf asi_blk_init vis2 vis popc These instructions are not-privileged, so are available for direct use in user-level applications and libraries (such as OpenSSL). Here is the "openssl speed -evp" command shown with the built-in t4 engine and with the pkcs11 engine. Both run the T4 AES instructions, but the t4 engine is faster than the pkcs11 engine because it has less overhead (especially for smaller packet sizes): t-4 $ /usr/bin/openssl version OpenSSL 1.0.0j 10 May 2012 t-4 $ /usr/bin/openssl engine (t4) SPARC T4 engine support (dynamic) Dynamic engine loading support (pkcs11) PKCS #11 engine support t-4 $ /usr/bin/openssl speed -evp aes-128-cbc # t4 engine used by default . . . The 'numbers' are in 1000s of bytes per second processed. type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes aes-128-cbc 487777.10k 816822.21k 986012.59k 1017029.97k 1053543.08k t-4 $ /usr/bin/openssl speed -engine pkcs11 -evp aes-128-cbc engine "pkcs11" set. . . . The 'numbers' are in 1000s of bytes per second processed. type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes aes-128-cbc 31703.58k 116636.39k 350672.81k 696170.50k 993599.49k Note: The "-evp" flag indicates use the OpenSSL "EnVeloPe" API, which gives more accurate results. That's because it tells OpenSSL to use the same API that external programs use when calling OpenSSL libcrypto functions, evp(3openssl). DTrace Shows if T4 Crypto Functions Are Used OK, good enough, the isainfo(1) command shows the instructions are present, but how does one know if they are being used? Chi-Chang Lin, who works on Oracle Solaris performance, wrote a Dtrace script to show if T4 instructions are being executed. To show the T4 instructions are being used, run the following Dtrace script. Look for functions named "t4" and "yf" in the output. The OpenSSL T4 engine uses functions named "t4" and the PKCS#11 engine uses functions named "yf". To demonstrate, I'll first run "openssl speed" with the built-in t4 engine then with the pkcs11 engine. The performance numbers are not valid due to dtrace probes slowing things down. t-4 # dtrace -Z -n ' pid$target::*yf*:entry,pid$target::*t4_*:entry{ @[probemod, probefunc] = count();}' \ -c "/usr/bin/openssl speed -evp aes-128-cbc" dtrace: description 'pid$target::*yf*:entry' matched 101 probes . . . dtrace: pid 2029 has exited libcrypto.so.1.0.0 ENGINE_load_t4 1 libcrypto.so.1.0.0 t4_DH 1 libcrypto.so.1.0.0 t4_DSA 1 libcrypto.so.1.0.0 t4_RSA 1 libcrypto.so.1.0.0 t4_destroy 1 libcrypto.so.1.0.0 t4_free_aes_ctr_NIDs 1 libcrypto.so.1.0.0 t4_init 1 libcrypto.so.1.0.0 t4_add_NID 3 libcrypto.so.1.0.0 t4_aes_expand128 5 libcrypto.so.1.0.0 t4_cipher_init_aes 5 libcrypto.so.1.0.0 t4_get_all_ciphers 6 libcrypto.so.1.0.0 t4_get_all_digests 59 libcrypto.so.1.0.0 t4_digest_final_sha1 65 libcrypto.so.1.0.0 t4_digest_init_sha1 65 libcrypto.so.1.0.0 t4_sha1_multiblock 126 libcrypto.so.1.0.0 t4_digest_update_sha1 261 libcrypto.so.1.0.0 t4_aes128_cbc_encrypt 1432979 libcrypto.so.1.0.0 t4_aes128_load_keys_for_encrypt 1432979 libcrypto.so.1.0.0 t4_cipher_do_aes_128_cbc 1432979 t-4 # dtrace -Z -n 'pid$target::*yf*:entry{ @[probemod, probefunc] = count();}   pid$target::*yf*:entry,pid$target::*t4_*:entry{ @[probemod, probefunc] = count();}' \ -c "/usr/bin/openssl speed -engine pkcs11 -evp aes-128-cbc" dtrace: description 'pid$target::*yf*:entry' matched 101 probes engine "pkcs11" set. . . . dtrace: pid 2033 has exited libcrypto.so.1.0.0 ENGINE_load_t4 1 libcrypto.so.1.0.0 t4_DH 1 libcrypto.so.1.0.0 t4_DSA 1 libcrypto.so.1.0.0 t4_RSA 1 libcrypto.so.1.0.0 t4_destroy 1 libcrypto.so.1.0.0 t4_free_aes_ctr_NIDs 1 libcrypto.so.1.0.0 t4_get_all_ciphers 1 libcrypto.so.1.0.0 t4_get_all_digests 1 libsoftcrypto.so.1 rijndael_key_setup_enc_yf 1 libsoftcrypto.so.1 yf_aes_expand128 1 libcrypto.so.1.0.0 t4_add_NID 3 libsoftcrypto.so.1 yf_aes128_cbc_encrypt 1542330 libsoftcrypto.so.1 yf_aes128_load_keys_for_encrypt 1542330 So, as shown above the OpenSSL built-in t4 engine executes t4_* functions (which are hand-coded assembly executing the T4 AES instructions) and the OpenSSL pkcs11 engine executes *yf* functions. Programmatic Use of OpenSSL T4 engine The OpenSSL t4 engine is used automatically with the /usr/bin/openssl command line. Chi-Chang Lin also points out that if you're calling the OpenSSL API (libcrypto.so) from a program, you must call ENGINE_load_built_engines(), otherwise the built-in t4 engine will not be loaded. You do not call ENGINE_set_default(). That's because "openssl speed -evp" test calls ENGINE_load_built_engines() even though the "-engine" option wasn't specified. OpenSSL T4 engine Availability The OpenSSL t4 engine is available with Solaris 11 and 11.1. For Solaris 10 08/11 (U10), you need to use the OpenSSL pkcs311 engine. The OpenSSL t4 engine is distributed only with the version of OpenSSL distributed with Solaris (and not third-party or self-compiled versions of OpenSSL). The OpenSSL engine implements the AES cipher for Solaris 11, released 11/2011. For Solaris 11.1, released 11/2012, the OpenSSL engine adds optimization for the MD5, SHA-1, and SHA-2 hash algorithms, and DES-3. Although the T4 processor has Camillia and Kasumi block cipher instructions, these are not implemented in the OpenSSL T4 engine. The following charts may help view availability of optimizations. The first chart shows what's available with Solaris CLIs and APIs, the second chart shows what's available in Solaris OpenSSL. Native Solaris Optimization for SPARC T4 This table is shows Solaris native CLI and API support. As such, they are all available with the OpenSSL pkcs11 engine. CLIs: "openssl -engine pkcs11", encrypt(1), decrypt(1), mac(1), digest(1), MD5sum(1), SHA1sum(1), SHA224sum(1), SHA256sum(1), SHA384sum(1), SHA512sum(1) APIs: PKCS#11 library libpkcs11(3LIB) (incluDES Openssl pkcs11 engine), libMD(3LIB), and Solaris kernel modules AlgorithmSolaris 1008/11 (U10)Solaris 11Solaris 11.1 AES-ECB, AES-CBC, AES-CTR, AES-CBC AES-CFB128 XXX DES3-ECB, DES3-CBC, DES2-ECB, DES2-CBC, DES-ECB, DES-CBC XXX bignum Montgomery multiply (RSA, DSA) XXX MD5, SHA-1, SHA-256, SHA-384, SHA-512 XXX SHA-224 X ARCFOUR (RC4) X Solaris OpenSSL T4 Engine Optimization This table is for the Solaris OpenSSL built-in t4 engine. Algorithms listed above are also available through the OpenSSL pkcs11 engine. CLI: openssl(1openssl) APIs: openssl(5), engine(3openssl), evp(3openssl), libcrypto crypto(3openssl) AlgorithmSolaris 11Solaris 11SRU2Solaris 11.1 AES-ECB, AES-CBC, AES-CTR, AES-CBC AES-CFB128 XXX DES3-ECB, DES3-CBC, DES-ECB, DES-CBC X bignum Montgomery multiply (RSA, DSA) X MD5, SHA-1, SHA-256, SHA-384, SHA-512 XX SHA-224 X Source Code Availability Solaris Most of the T4 assembly code that called the new T4 crypto instructions was written by Ferenc Rákóczi of the Solaris Security group, with assistance from others. You can download the Solaris source for this and other parts of Solaris as a few zip files at the Oracle Download website. The relevant source files are generally under directories usr/src/common/crypto/{aes,arcfour,des,md5,modes,sha1,sha2}}/sun4v/. and usr/src/common/bignum/sun4v/. Solaris 11 binary is available from the Oracle Solaris 11 download website. OpenSSL t4 engine The source for the OpenSSL t4 engine, which is based on the Solaris source above, is viewable through the OpenGrok source code browser in directory src/components/openssl/openssl-1.0.0/engines/t4 . You can download the source from the same website or through Mercurial source code management, hg(1). Conclusion Oracle Solaris with SPARC T4 provides a rich set of accelerated cryptographic and hash algorithms. Using the latest update, Solaris 11.1, provides the best set of optimized algorithms, but alternatives are often available, sometimes slightly slower, for releases back to Solaris 10 08/11 (U10). Reference See also these earlier blogs. SPARC T4 OpenSSL Engine by myself, Dan Anderson (2011), discusses the Openssl T4 engine and reviews the SPARC T4 processor for the Solaris 11 release. Exciting Crypto Advances with the T4 processor and Oracle Solaris 11 by Valerie Fenwick (2011) discusses crypto algorithms that were optimized for the T4 processor with the Solaris 11 FCS (11/11) and Solaris 10 08/11 (U10) release. T4 Crypto Cheat Sheet by Stefan Hinker (2012) discusses how to make T4 crypto optimization available to various consumers (such as SSH, Java, OpenSSL, Apache, etc.) High Performance Security For Oracle Database and Fusion Middleware Applications using SPARC T4 (PDF, 2012) discusses SPARC T4 and its usage to optimize application security. Configuring Oracle iPlanet WebServer / Oracle Traffic Director to use crypto accelerators on T4-1 servers by Meena Vyas (2012)

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  • ODI 11g - Scripting a Reverse Engineer

    - by David Allan
    A common question is related to how to script the reverse engineer using the ODI SDK. This follows on from some of my posts on scripting in general and accelerated model and topology setup. Check out this viewlet here to see how to define a reverse engineering process using ODI's package. Using the ODI SDK, you can script this up using the OdiPackage and StepOdiCommand classes as follows;  OdiPackage pkg = new OdiPackage(folder, "Pkg_Rev"+modName);   StepOdiCommand step1 = new StepOdiCommand(pkg,"step1_cmd_reset");   step1.setCommandExpression(new Expression("OdiReverseResetTable \"-MODEL="+mod.getModelId()+"\"",null, Expression.SqlGroupType.NONE));   StepOdiCommand step2 = new StepOdiCommand(pkg,"step2_cmd_reset");   step2.setCommandExpression(new Expression("OdiReverseGetMetaData \"-MODEL="+mod.getModelId()+"\"",null, Expression.SqlGroupType.NONE));   StepOdiCommand step3 = new StepOdiCommand(pkg,"step3_cmd_reset");   step3.setCommandExpression(new Expression("OdiReverseSetMetaData \"-MODEL="+mod.getModelId()+"\"",null, Expression.SqlGroupType.NONE));   pkg.setFirstStep(step1);   step1.setNextStepAfterSuccess(step2);   step2.setNextStepAfterSuccess(step3); The biggest leap of faith for users is getting to know which SDK classes have to be used to build the objects in the design, using StepOdiCommand isn't necessarily obvious, once you see it in action though it is very simple to use. The above snippet uses an OdiModel variable named mod, its a snippet I added to the accelerated model creation script in the post linked above.

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  • 8 Reasons Why Even Microsoft Agrees the Windows Desktop is a Nightmare

    - by Chris Hoffman
    Let’s be honest: The Windows desktop is a mess. Sure, it’s extremely powerful and has a huge software library, but it’s not a good experience for average people. It’s not even a good experience for geeks, although we tolerate it. Even Microsoft agrees about this. Microsoft’s Surface tablets with Windows RT don’t support any third-party desktop apps. They consider this a feature — users can’t install malware and other desktop junk, so the system will always be speedy and secure. Malware is Still Common Malware may not affect geeks, but it certainly continues to affect average people. Securing Windows, keeping it secure, and avoiding unsafe programs is a complex process. There are over 50 different file extensions that can contain harmful code to keep track of. It’s easy to have theoretical discussions about how malware could infect Mac computers, Android devices, and other systems. But Mac malware is extremely rare, and has  generally been caused by problem with the terrible Java plug-in. Macs are configured to only run executables from identified developers by default, whereas Windows will run everything. Android malware is talked about a lot, but Android malware is rare in the real world and is generally confined to users who disable security protections and install pirated apps. Google has also taken action, rolling out built-in antivirus-like app checking to all Android devices, even old ones running Android 2.3, via Play Services. Whatever the reason, Windows malware is still common while malware for other systems isn’t. We all know it — anyone who does tech support for average users has dealt with infected Windows computers. Even users who can avoid malware are stuck dealing with complex and nagging antivirus programs, especially since it’s now so difficult to trust Microsoft’s antivirus products. Manufacturer-Installed Bloatware is Terrible Sit down with a new Mac, Chromebook, iPad, Android tablet, Linux laptop, or even a Surface running Windows RT and you can enjoy using your new device. The system is a clean slate for you to start exploring and installing your new software. Sit down with a new Windows PC and the system is a mess. Rather than be delighted, you’re stuck reinstalling Windows and then installing the necessary drivers or you’re forced to start uninstalling useless bloatware programs one-by-one, trying to figure out which ones are actually useful. After uninstalling the useless programs, you may end up with a system tray full of icons for ten different hardware utilities anyway. The first experience of using a new Windows PC is frustration, not delight. Yes, bloatware is still a problem on Windows 8 PCs. Manufacturers can customize the Refresh image, preventing bloatware rom easily being removed. Finding a Desktop Program is Dangerous Want to install a Windows desktop program? Well, you’ll have to head to your web browser and start searching. It’s up to you, the user, to know which programs are safe and which are dangerous. Even if you find a website for a reputable program, the advertisements on that page will often try to trick you into downloading fake installers full of adware. While it’s great to have the ability to leave the app store and get software that the platform’s owner hasn’t approved — as on Android — this is no excuse for not providing a good, secure software installation experience for typical users installing typical programs. Even Reputable Desktop Programs Try to Install Junk Even if you do find an entirely reputable program, you’ll have to keep your eyes open while installing it. It will likely try to install adware, add browse toolbars, change your default search engine, or change your web browser’s home page. Even Microsoft’s own programs do this — when you install Skype for Windows desktop, it will attempt to modify your browser settings t ouse Bing, even if you’re specially chosen another search engine and home page. With Microsoft setting such an example, it’s no surprise so many other software developers have followed suit. Geeks know how to avoid this stuff, but there’s a reason program installers continue to do this. It works and tricks many users, who end up with junk installed and settings changed. The Update Process is Confusing On iOS, Android, and Windows RT, software updates come from a single place — the app store. On Linux, software updates come from the package manager. On Mac OS X, typical users’ software updates likely come from the Mac App Store. On the Windows desktop, software updates come from… well, every program has to create its own update mechanism. Users have to keep track of all these updaters and make sure their software is up-to-date. Most programs now have their act together and automatically update by default, but users who have old versions of Flash and Adobe Reader installed are vulnerable until they realize their software isn’t automatically updating. Even if every program updates properly, the sheer mess of updaters is clunky, slow, and confusing in comparison to a centralized update process. Browser Plugins Open Security Holes It’s no surprise that other modern platforms like iOS, Android, Chrome OS, Windows RT, and Windows Phone don’t allow traditional browser plugins, or only allow Flash and build it into the system. Browser plugins provide a wealth of different ways for malicious web pages to exploit the browser and open the system to attack. Browser plugins are one of the most popular attack vectors because of how many users have out-of-date plugins and how many plugins, especially Java, seem to be designed without taking security seriously. Oracle’s Java plugin even tries to install the terrible Ask toolbar when installing security updates. That’s right — the security update process is also used to cram additional adware into users’ machines so unscrupulous companies like Oracle can make a quick buck. It’s no wonder that most Windows PCs have an out-of-date, vulnerable version of Java installed. Battery Life is Terrible Windows PCs have bad battery life compared to Macs, IOS devices, and Android tablets, all of which Windows now competes with. Even Microsoft’s own Surface Pro 2 has bad battery life. Apple’s 11-inch MacBook Air, which has very similar hardware to the Surface Pro 2, offers double its battery life when web browsing. Microsoft has been fond of blaming third-party hardware manufacturers for their poorly optimized drivers in the past, but there’s no longer any room to hide. The problem is clearly Windows. Why is this? No one really knows for sure. Perhaps Microsoft has kept on piling Windows component on top of Windows component and many older Windows components were never properly optimized. Windows Users Become Stuck on Old Windows Versions Apple’s new OS X 10.9 Mavericks upgrade is completely free to all Mac users and supports Macs going back to 2007. Apple has also announced their intention that all new releases of Mac OS X will be free. In 2007, Microsoft had just shipped Windows Vista. Macs from the Windows Vista era are being upgraded to the latest version of the Mac operating system for free, while Windows PCs from the same era are probably still using Windows Vista. There’s no easy upgrade path for these people. They’re stuck using Windows Vista and maybe even the outdated Internet Explorer 9 if they haven’t installed a third-party web browser. Microsoft’s upgrade path is for these people to pay $120 for a full copy of Windows 8.1 and go through a complicated process that’s actaully a clean install. Even users of Windows 8 devices will probably have to pay money to upgrade to Windows 9, while updates for other operating systems are completely free. If you’re a PC geek, a PC gamer, or someone who just requires specialized software that only runs on Windows, you probably use the Windows desktop and don’t want to switch. That’s fine, but it doesn’t mean the Windows desktop is actually a good experience. Much of the burden falls on average users, who have to struggle with malware, bloatware, adware bundled in installers, complex software installation processes, and out-of-date software. In return, all they get is the ability to use a web browser and some basic Office apps that they could use on almost any other platform without all the hassle. Microsoft would agree with this, touting Windows RT and their new “Windows 8-style” app platform as the solution. Why else would Microsoft, a “devices and services” company, position the Surface — a device without traditional Windows desktop programs — as their mass-market device recommended for average people? This isn’t necessarily an endorsement of Windows RT. If you’re tech support for your family members and it comes time for them to upgrade, you may want to get them off the Windows desktop and tell them to get a Mac or something else that’s simple. Better yet, if they get a Mac, you can tell them to visit the Apple Store for help instead of calling you. That’s another thing Windows PCs don’t offer — good manufacturer support. Image Credit: Blanca Stella Mejia on Flickr, Collin Andserson on Flickr, Luca Conti on Flickr     

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  • Should interfaces extend (and in doing so inherit methods of) other interfaces

    - by dreza
    Although this is a general question it is also specific to a problem I am currently experiencing. I currently have an interface specified in my solution called public interface IContextProvider { IDataContext { get; set; } IAreaContext { get; set; } } This interface is often used throughout the program and hence I have easy access to the objects I need. However at a fairly low level of a part of my program I need access to another class that will use IAreaContext and perform some operations off it. So I have created another factory interface to do this creation called: public interface IEventContextFactory { IEventContext CreateEventContext(int eventId); } I have a class that implements the IContextProvider and is injected using NinJect. The problem I have is that the area where I need to use this IEventContextFactory has access to the IContextProvider only and itself uses another class which will need this new interface. I don't want to have to instantiate this implementation of IEventContextFactory at the low level and would rather work with the IEventContextFactory interface throughout. However I also don't want to have to inject another parameter through the constructors just to have it passed through to the class that needs it i.e. // example of problem public class MyClass { public MyClass(IContextProvider context, IEventContextFactory event) { _context = context; _event = event; } public void DoSomething() { // the only place _event is used in the class is to pass it through var myClass = new MyChildClass(_event); myClass.PerformCalculation(); } } So my main question is, would this be acceptable or is it even common or good practice to do something like this (interface extend another an interface): public interface IContextProvider : IEventContextFactory or should I consider better alternatives to achieving what I need. If I have not provided enough information to give suggestions let me know and I can provide more.

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  • Database Connectivity Test with UDL File

    - by Ben Griswold
    I bounced around between projects a lot last week.  What each project had in common was the need to validate at least one SQL connection.  Whether you have SQL tools like SSMS installed or not, this is a very easy task if you are aware of the UDL (Universal Data Link) files.  Create a new file and name it anything as long as it has the .udl extension. Open the file, choose a provider: Click Next >> or navigate to the Connection Tab to provide connection information.  Once you provide server and login credentials, the database list will populate.  At this point, you know the connection is valid. but go ahead and click the Test Connection button anyway. On the final tab, you can provide extra connection information like Application Name which can come in handy.  The All tab is beneficial if you want to build a valid connection string to include in your own applications.  If you save the file and then open in Notepad, you’ll find that said connection string: Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=master;Data Source=(local);Application Name=TestApp I hope this tip helps save you some time.  How do you test if you don’t have SSMS installed?

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