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  • Does Ubuntu run on current Asus Transformer Prime?

    - by Ubuntu User
    I've read instructions about dual boot Android / Transformer Prime (a significant factor in ordering one). Also about not working with /latest/ Transformer Prime (firmware / BIOS?) Also about imminent Ubuntu ARM support. Will I be able to run Ubuntu in a day or two when Transformer arrives? Also, am I right to assume I can restore Transformer to factory status if I break something in the attempt?

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  • Friday Fun: Stream Master Unlimited

    - by Asian Angel
    In this week’s game your puzzle solving skills will be tested as you work to build paths between all the colored power nodes on each grid. With 300 puzzle grids and three difficulty levels to challenge you, will you be able to successfully connect all the power nodes from beginning to end in the game? Secure Yourself by Using Two-Step Verification on These 16 Web Services How to Fix a Stuck Pixel on an LCD Monitor How to Factory Reset Your Android Phone or Tablet When It Won’t Boot

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  • Can't return to stock Android

    - by kurt
    Whenever I try and uncompress the tar file, I get this: tar (child): nakasi-jro03d-factory-e102ba72.tg: Cannot open: No such file or directory tar (child): Error is not recoverable: exiting now tar: Child returned status 2 tar: Error is not recoverable: exiting now I'm fairly new to Ubuntu. So I'm pretty sure that's my fault. So I just compress it manually using the GUI. But when I try to flash it, I get sudo: ./flash-all.sh: command not found Please help.

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  • Answers to Your Common Oracle Database Lifecycle Management Questions

    - by Scott McNeil
    We recently ran a live webcast on Strategies for Managing Oracle Database's Lifecycle. There were tons of questions from our audience that we simply could not get to during the hour long presentation. Below are some of those questions along with their answers. Enjoy! Question: In the webcast the presenter talked about “gold” configuration standards, for those who want to use this technique, could you recommend a best practice to consider or follow? How do I get started? Answer:Gold configuration standardization is a quick and easy way to improve availability through consistency. Start by choosing a reference database and saving the configuration to the Oracle Enterprise Manager repository using the Save Configuration feature. Next create a comparison template using the Oracle provided template as a starting point and modify the ignored properties to eliminate expected differences in your environment. Finally create a comparison specification using the comparison template you created plus your saved gold configuration and schedule it to run on a regular basis. Don’t forget to fill in the email addresses of those you want to notify upon drift detection. Watch the database configuration management demo to learn more. Question: Can Oracle Lifecycle Management Pack for Database help with patching an Oracle Real Application Cluster (RAC) environment? Answer: Yes, Oracle Enterprise Manager supports both parallel and rolling patch application of Oracle Real Application Clusters. The use of rolling patching is recommended as there is no downtime involved. For more details watch this demo. Question: What are some of the things administrators can do to control configuration drift? Why is it important? Answer:Configuration drift is one of the main causes of instability and downtime of applications. Oracle Enterprise Manager makes it easy to manage and control drift using scheduled configuration comparisons combined with comparison templates. Question: Does Oracle Enterprise Manager 12c Release 2 offer an incremental update feature for "gold" images? For instance, if the source binary has a higher PSU level, what is the best approach to update the existing "gold" image in the software library? Do you have to create a new image or can you just update the original one? Answer:Provisioning Profiles (Gold images) can contain the installation files and database configuration templates. Although it is possible to make some changes to the profile after creation (mainly to configuration), it is normally recommended to simply create a new profile after applying a patch to your reference database. Question: The webcast talked about enforcing in-house standards, does Oracle Enterprise Manager 12c offer verification of your databases and systems to those standards? For example, the initial "gold" image has been massively deployed over time, and there may be some changes to it. How can you do regular checks from Enterprise Manager to ensure the in-house standards are being enforced? Answer:There are really two methods to validate conformity to standards. The first method is to use gold standards which you compare other databases to report unwanted differences. This method uses a new comparison template technology which allows users to ignore known differences (i.e. SID, Start time, etc) which results in a report only showing important or non-conformant differences. This method is quick to setup and configure and recommended for those who want to get started validating compliance quickly. The second method leverages the new compliance framework which allows the creation of specific and robust validations. These compliance rules are grouped into standards which can be assigned to databases quickly and easily. Compliance rules allow for targeted and more sophisticated validation beyond the basic equals operation available in the comparison method. The compliance framework can be used to implement just about any internal or industry standard. The compliance results will track current and historic compliance scores at the overall and individual database targets. When the issue is resolved, the score is automatically affected. Compliance framework is the recommended long term solution for validating compliance using Oracle Enterprise Manager 12c. Check out this demo on database compliance to learn more. Question: If you are using the integration between Oracle Enterprise Manager and My Oracle Support in an "offline" mode, how do you know if you have the latest My Oracle Support metadata? Answer:In Oracle Enterprise Manager 12c Release 2, you now only need to download one zip file containing all of the metadata xmls files. There is no indication that the metadata has changed but you could run a checksum on the file and compare it to the previously downloaded version to see if it has changed. Question: What happens if a patch fails while administrators are applying it to a database or system? Answer:A large portion of Oracle Enterprise Manager's patch automation is the pre-requisite checks that happen to ensure the highest level of confidence the patch will successfully apply. It is recommended you test the patch in a non-production environment and save the patch plan as a template once successful so you can create new plans using the saved template. If you are using the recommended ‘out of place’ patching methodology, there is no urgency because the database is still running as the cloned Oracle home is being patched. Users can address the issue and restart the patch procedure at the point it left off. If you are using 'in place' method, you can address the issue and continue where the procedure left off. Question: Can Oracle Enterprise Manager 12c R2 compare configurations between more than one target at the same time? Answer:Oracle Enterprise Manager 12c can compare any number of target configurations at one time. This is the basis of many important use cases including Configuration Drift Management. These comparisons can also be scheduled on a regular basis and emails notification sent should any differences appear. To learn more about configuration search and compare watch this demo. Question: How is data comparison done since changes are taking place in a live production system? Answer:There are many things to keep in mind when using the data comparison feature (as part of the Change Management ability to compare table data). It was primarily intended to be used for maintaining consistency of important but relatively static data. For example, application seed data and application setup configuration. This data does not change often but is critical when testing an application to ensure results are consistent with production. It is not recommended to use data comparison on highly dynamic data like transactional tables or very large tables. Question: Which versions of Oracle Database can be monitored through Oracle Enterprise Manager 12c? Answer:Oracle Database versions: 9.2.0.8, 10.1.0.5, 10.2.0.4, 10.2.0.5, 11.1.0.7, 11.2.0.1, 11.2.0.2, 11.2.0.3. Watch the On-Demand Webcast Stay Connected: Twitter | Facebook | YouTube | Linkedin | NewsletterDownload the Oracle Enterprise Manager Cloud Control12c Mobile app

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  • c# class naming standards/guidelines

    - by Ben
    Over the years I've used various naming conventions for services in my applications for example: [ClassName]Service [ClassName]Manager [ClassName]Factory [ClassName]Provider [ClassName]Helper I generally only use the "Helper" suffix for utility classes that have no external dependencies. However I find that there is a bit of a cross-over between the others, and wondered if there was any recommendations/standards/guidelines on what to use and when?

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  • Presenting at SQLConnections!

    - by andyleonard
    Introduction This year I'm honored to present at SQLConnections in Orlando 27-30 Mar 2011! My topics are Database Design for Developers, Build Your First SSIS Package, and Introduction to Incremental Loads. Database Design for Developers This interactive session is for software developers tasked with database development. Attend and learn about patterns and anti-patterns of database development, one method for building re-executable Transact-SQL deployment scripts, a method for using SqlCmd to deploy...(read more)

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  • OpenGL 2.1+ Render with data returned form assimp library

    - by Bình Nguyên
    I have just readed this tutorial about load a 3D model file: http://www.lighthouse3d.com/cg-topics/code-samples/importing-3d-models-with-assimp/#comment-14551. Its render routine uses a recursive_render function to scan all node. My question: What is a aiNode struct store? What different form this method and above method: for (int i=0; imNumMesh; ++i) { draw scene-mMeshes[i]; } Thanks for reading!

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  • LINQ: Enhancing Distinct With The SelectorEqualityComparer

    - by Paulo Morgado
    On my last post, I introduced the PredicateEqualityComparer and a Distinct extension method that receives a predicate to internally create a PredicateEqualityComparer to filter elements. Using the predicate, greatly improves readability, conciseness and expressiveness of the queries, but it can be even better. Most of the times, we don’t want to provide a comparison method but just to extract the comaprison key for the elements. So, I developed a SelectorEqualityComparer that takes a method that extracts the key value for each element. Something like this: public class SelectorEqualityComparer<TSource, Tkey> : EqualityComparer<TSource> where Tkey : IEquatable<Tkey> { private Func<TSource, Tkey> selector; public SelectorEqualityComparer(Func<TSource, Tkey> selector) : base() { this.selector = selector; } public override bool Equals(TSource x, TSource y) { Tkey xKey = this.GetKey(x); Tkey yKey = this.GetKey(y); if (xKey != null) { return ((yKey != null) && xKey.Equals(yKey)); } return (yKey == null); } public override int GetHashCode(TSource obj) { Tkey key = this.GetKey(obj); return (key == null) ? 0 : key.GetHashCode(); } public override bool Equals(object obj) { SelectorEqualityComparer<TSource, Tkey> comparer = obj as SelectorEqualityComparer<TSource, Tkey>; return (comparer != null); } public override int GetHashCode() { return base.GetType().Name.GetHashCode(); } private Tkey GetKey(TSource obj) { return (obj == null) ? (Tkey)(object)null : this.selector(obj); } } Now I can write code like this: .Distinct(new SelectorEqualityComparer<Source, Key>(x => x.Field)) And, for improved readability, conciseness and expressiveness and support for anonymous types the corresponding Distinct extension method: public static IEnumerable<TSource> Distinct<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> selector) where TKey : IEquatable<TKey> { return source.Distinct(new SelectorEqualityComparer<TSource, TKey>(selector)); } And the query is now written like this: .Distinct(x => x.Field) For most usages, it’s simpler than using a predicate.

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  • The Fellowship of the Ringwraiths [Video]

    - by Asian Angel
    While we all know what happened during the events of the first LOTR movie for the Fellowship, there were some unanswered questions about the Ringwraiths and their activities. Here finally is your opportunity to see what really happened… Fellowship of the Ringwraiths [via Neatorama] How to Factory Reset Your Android Phone or Tablet When It Won’t Boot Our Geek Trivia App for Windows 8 is Now Available Everywhere How To Boot Your Android Phone or Tablet Into Safe Mode

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  • Draw a never-ending line in XNA

    - by user2236165
    I am drawing a line in XNA which I want to never end. I also have a tool that moves forward in X-direction and a camera which is centered at this tool. However, when I reach the end of the viewport the lines are not drawn anymore. Here are some pictures to illustrate my problem: At the start the line goes across the whole screen, but as my tool moves forward, we reach the end of the line. Here are the method which draws the lines: private void DrawEvenlySpacedSprites (Texture2D texture, Vector2 point1, Vector2 point2, float increment) { var distance = Vector2.Distance (point1, point2); // the distance between two points var iterations = (int)(distance / increment); // how many sprites with be drawn var normalizedIncrement = 1.0f / iterations; // the Lerp method needs values between 0.0 and 1.0 var amount = 0.0f; if (iterations == 0) iterations = 1; for (int i = 0; i < iterations; i++) { var drawPoint = Vector2.Lerp (point1, point2, amount); spriteBatch.Draw (texture, drawPoint, Color.White); amount += normalizedIncrement; } } Here are the draw method in Game. The dots are my lines: protected override void Draw (GameTime gameTime) { graphics.GraphicsDevice.Clear(Color.Black); nyVector = nextVector (gammelVector); GraphicsDevice.SetRenderTarget (renderTarget); spriteBatch.Begin (); DrawEvenlySpacedSprites (dot, gammelVector, nyVector, 0.9F); spriteBatch.End (); GraphicsDevice.SetRenderTarget (null); spriteBatch.Begin (SpriteSortMode.Deferred, BlendState.AlphaBlend, null, null, null, null, camera.transform); spriteBatch.Draw (renderTarget, new Vector2 (), Color.White); spriteBatch.Draw (tool, new Vector2(toolPos.X - (tool.Width/2), toolPos.Y - (tool.Height/2)), Color.White); spriteBatch.End (); gammelVector = new Vector2 (nyVector.X, nyVector.Y); base.Draw (gameTime); } Here's the next vector-method, It just finds me a new point where the line should be drawn with a new X-coordinate between 100 and 200 pixels and a random Y-coordinate between the old vector Y-coordinate and the height of the viewport: Vector2 nextVector (Vector2 vector) { return new Vector2 (vector.X + r.Next(100, 200), r.Next ((int)(vector.Y - 100), viewport.Height)); } Can anyone point me in the right direction here? I'm guessing it has to do with the viewport.width, but I'm not quite sure how to solve it. Thank you for reading!

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  • Programmatically navigate to a new page

    - by [email protected]
    Did you know you can programmatically navigate to a new page via code?  Inside your bean method, you can simply use the NavigationDispatchHelper class to do the work for you. The invokePageNavigation method of NavigationDispatchHelper takes a String parameter that holds the value of the navigation rule to follow.   import oracle.adfnmc.util.NavigationDispatchHelper; public void MyBeanMethod() { /'/ Do stuff NavigationDispatchHelper.invokePageNavigation("patients"); }

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  • Stairway to XML: Level 4 - Querying XML Data

    You can extract a subset of data from an XML instance by using the query() method, and you can use the value() method to retrieve individual element and attribute values from an XML instance. SQL Monitor v3 is even more powerfulUse custom metrics to monitor and alert on data that's most important for your environment, easily imported from our custom metrics site. Find out more.

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  • Issues with touch buttons in XNA (Release state to be precise)

    - by Aditya
    I am trying to make touch buttons in WP8 with all the states (Pressed, Released, Moved), but the TouchLocationState.Released is not working. Here's my code: Class variables: bool touching = false; int touchID; Button tempButton; Button is a separate class with a method to switch states when touched. The Update method contains the following code: TouchCollection touchCollection = TouchPanel.GetState(); if (!touching && touchCollection.Count > 0) { touching = true; foreach (TouchLocation location in touchCollection) { for (int i = 0; i < menuButtons.Count; i++) { touchID = location.Id; // store the ID of current touch Point touchLocation = new Point((int)location.Position.X, (int)location.Position.Y); // create a point Button button = menuButtons[i]; if (GetMenuEntryHitBounds(button).Contains(touchLocation)) // a method which returns a rectangle. { button.SwitchState(true); // change the button state tempButton = button; // store the pressed button for accessing later } } } } else if (touchCollection.Count == 0) // clears the state of all buttons if no touch is detected { touching = false; for (int i = 0; i < menuButtons.Count; i++) { Button button = menuButtons[i]; button.SwitchState(false); } } menuButtons is a list of buttons on the menu. A separate loop (within the Update method) after the touched variable is true if (touching) { TouchLocation location; TouchLocation prevLocation; if (touchCollection.FindById(touchID, out location)) { if (location.TryGetPreviousLocation(out prevLocation)) { Point point = new Point((int)location.Position.X, (int)location.Position.Y); if (prevLocation.State == TouchLocationState.Pressed && location.State == TouchLocationState.Released) { if (GetMenuEntryHitBounds(tempButton).Contains(point)) // Execute the button action. I removed the excess } } } } The code for switching the button state is working fine but the code where I want to trigger the action is not. location.State == TouchLocationState.Released mostly ends up being false. (Even after I release the touch, it has a value of TouchLocationState.Moved) And what is more irritating is that it sometimes works! I am really confused and stuck for days now. Is this the right way? If yes then where am I going wrong? Or is there some other more effective way to do this? PS: I also posted this question on stack overflow then realized this question is more appropriate in gamedev. Sorry if it counts as being redundant.

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  • Desktop Fun: Christmas 2012 Wallpaper Collection [Bonus Edition]

    - by Asian Angel
    Christmas will soon be here and we have just what you need to help make your desktop as beautiful and colorful as the holiday itself. Add the perfect touch of holiday charm to your desktop with our Christmas 2012 Wallpaper collection. Secure Yourself by Using Two-Step Verification on These 16 Web Services How to Fix a Stuck Pixel on an LCD Monitor How to Factory Reset Your Android Phone or Tablet When It Won’t Boot

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  • SCSF for Visual Studio 2010

    - by Anthony Trudeau
    The Smart Client Software Factory (SCSF) for Visual Studio 2010 was uploaded tonight.  You can get it, the source code, and the documentation on the patterns & practices page. Note: Do not forget to "unblock" the documentation (CHM) file after you download it.  To unblock it right click the file, choose Properties, and click the Unblock button.

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  • To access parentAM instance from within nestedAM JUnit test class

    - by Abhishek Dwivedi
    In normal model project, the way to access parent AM from within nested AM is simple - ParentAMImpl parentAM =  (ParentAMImpl)this.getRootApplicationModule(); However, the same approach doesn't help in JUnit model project. Use the following approach -  Inside setUp() method --  ParentAM parentAM =  (ParentAM)Configuration.createRootApplicationModule(ROOT_AM, ROOT_AM_CONFIG); Inside tearDown() method -- Configuration.releaseRootApplicationModule(parentAM, true);

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  • How do you exclude yourself from Google Analytics on your website using cookies?

    - by Cold Hawaiian
    I'm trying to set up an exclusion filter with a browser cookie, so that my own visits to my don't show up in my Google Analytics. I tried 3 different methods and none of them have worked so far. I would like help understanding what I am doing wrong and how I can fix this. Method 1 First, I tried following Google's instructions, http://www.google.com/support/analytics/bin/answer.py?hl=en&answer=55481, for excluding traffic by Cookie Content: Create a new page on your domain, containing the following code: <body onLoad="javascript:pageTracker._setVar('test_value');"> Method 2 Next, when that didn't work, I googled around and found this Google thread, http://www.google.com/support/forum/p/Google%20Analytics/thread?tid=4741f1499823fcd5&hl=en, where the most popular answer says to use a slightly different code: SHS Analytics wrote: <body onLoad="javascript:_gaq.push(['_setVar','test_value']);"> Thank you! This has now set a __utmv cookie containing "test_value", whereas the original: pageTracker._setVar('test_value') (which Google is still recommending) did not manage to do that for me (in Mac Safari 5 and Firefox 3.6.8). So I tried this code, but it didn't work for me. Method 3 Finally, I searched StackOverflow and came across this thread, http://stackoverflow.com/questions/3495270/exclude-my-traffic-from-google-analytics-using-cookie-with-subdomain, which suggests that the following code might work: <script type="text/javascript"> var _gaq = _gaq || []; _gaq.push(['_setVar', 'exclude_me']); _gaq.push(['_setAccount', 'UA-xxxxxxxx-x']); _gaq.push(['_trackPageview']); // etc... </script> This script appeared in the head element in the example, instead of in the onload event of the body like in the previous 2 examples. So I tried this too, but still had no luck with trying to exclude myself from Google Analytics. Re-iterate question So, I tried all 3 methods above with no success. Am I doing something wrong? How can I exclude myself from my Google Analytics using an exclusion cookie for my browser? Update I've been testing this for several days now, and I've confirmed that the 2nd method of excluding yourself from tracking does indeed work. The problem was that the filter settings weren't properly applied to my profile, which has been corrected. See the accepted answer below.

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  • Subterranean IL: Volatile

    - by Simon Cooper
    This time, we'll be having a look at the volatile. prefix instruction, and one of the differences between volatile in IL and C#. The volatile. prefix volatile is a tricky one, as there's varying levels of documentation on it. From what I can see, it has two effects: It prevents caching of the load or store value; rather than reading or writing to a cached version of the memory location (say, the processor register or cache), it forces the value to be loaded or stored at the 'actual' memory location, so it is then immediately visible to other threads. It forces a memory barrier at the prefixed instruction. This ensures instructions don't get re-ordered around the volatile instruction. This is slightly more complicated than it first seems, and only seems to matter on certain architectures. For more details, Joe Duffy has a blog post going into the details. For this post, I'll be concentrating on the first aspect of volatile. Caching field accesses To demonstrate this, I created a simple multithreaded IL program. It boils down to the following code: .class public Holder { .field public static class Holder holder .field public bool stop .method public static specialname void .cctor() { newobj instance void Holder::.ctor() stsfld class Holder Holder::holder ret }}.method private static void Main() { .entrypoint // Thread t = new Thread(new ThreadStart(DoWork)) // t.Start() // Thread.Sleep(2000) // Console.WriteLine("Stopping thread...") ldsfld class Holder Holder::holder ldc.i4.1 stfld bool Holder::stop call instance void [mscorlib]System.Threading.Thread::Join() ret}.method private static void DoWork() { ldsfld class Holder Holder::holder // while (!Holder.holder.stop) {} DoWork: dup ldfld bool Holder::stop brfalse DoWork pop ret} If you compile and run this code, you'll find that the call to Thread.Join() never returns - the DoWork spinlock is reading a cached version of Holder.stop, which is never being updated with the new value set by the Main method. Adding volatile to the ldfld fixes this: dupvolatile.ldfld bool Holder::stopbrfalse DoWork The volatile ldfld forces the field access to read direct from heap memory, which is then updated by the main thread, rather than using a cached copy. volatile in C# This highlights one of the differences between IL and C#. In IL, volatile only applies to the prefixed instruction, whereas in C#, volatile is specified on a field to indicate that all accesses to that field should be volatile (interestingly, there's no mention of the 'no caching' aspect of volatile in the C# spec; it only focuses on the memory barrier aspect). Furthermore, this information needs to be stored within the assembly somehow, as such a field might be accessed directly from outside the assembly, but there's no concept of a 'volatile field' in IL! How this information is stored with the field will be the subject of my next post.

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  • How did you get good practices for your OOP designs?

    - by Darf Zon
    I realized I have a difficulty creating OOP designs. I spent many time deciding if this property is correctly set it to X class. For example, this is a post which has a few days: http://codereview.stackexchange.com/questions/8041/how-to-improve-my-factory-design I'm not convinced of my code. So I want to improve my designs, take less time creating it. How did you learn creating good designs? Some books that you can recommend me?

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  • iPad2 - Yet Another Fundamental Defect in an Apple product

    - by Kit Ong
    First it was antenna defect in iPhone4 now it has been reported that some iPad 2 have display issues, Apple really needs to look at their manufacturing process. It doesn't help that workers are working like robots in their main supplier's factory Foxconn. More info on reported display light bleeding http://www.cultofmac.com/if-your-ipad-2-has-display-problems-do-not-return-it-heres-why/87197   How to check your iPad for dead pixel / light leak / bleed http://www.theipadguide.com/content/ipad-dead-pixel-test-how/7171269

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  • Christmas Captured with LEGO Star Wars

    - by Jason Fitzpatrick
    Combine the mini figures and modules from a LEGO Star Wars Advent Calendar with some creative photography, and you’ve got yourself a recipe for this some rather fun Star Wars-themed Christmas photos. LEGO Star Wars Advent Calendar Photos [Flickr via Boing Boing] Secure Yourself by Using Two-Step Verification on These 16 Web Services How to Fix a Stuck Pixel on an LCD Monitor How to Factory Reset Your Android Phone or Tablet When It Won’t Boot

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  • Uploaded Four New ADF Examples

    - by Steve Muench
    I've uploaded four new examples for your learning pleasure:  162. Set Binding to Attr Value from Selected SelectBooleanRadio Button in Data-Driven Button Group 163. Binding SelectBooleanRadio to True/False Value in DB Row 164. Method Action Invoking Managed Bean Method Without Making Bean a DataControl 165. Using a Headless Taskflow to Perform Work in an Autononmous Transaction Enjoy.

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  • Liskov principle: violation by type-hinting

    - by Elias Van Ootegem
    According to the Liskov principle, a construction like the one below is invalid, as it strengthens a pre-condition. I know the example is pointless/nonsense, but when I last asked a question like this, and used a more elaborate code sample, it seemed to distract people too much from the actual question. //Data models abstract class Argument { protected $value = null; public function getValue() { return $this->value; } abstract public function setValue($val); } class Numeric extends Argument { public function setValue($val) { $this->value = $val + 0;//coerce to number return $this; } } //used here: abstract class Output { public function printValue(Argument $arg) { echo $this->format($arg); return $this; } abstract public function format(Argument $arg); } class OutputNumeric extends Output { public function format(Numeric $arg)//<-- VIOLATION! { $format = is_float($arg->getValue()) ? '%.3f' : '%d'; return sprintf($format, $arg->getValue()); } } My question is this: Why would this kind of "violation" be considered harmful? So much so that some languages, like the one I used in this example (PHP), don't even allow this? I'm not allowed to strengthen the type-hint of an abstract method but, by overriding the printValue method, I am allowed to write: class OutputNumeric extends Output { final public function printValue(Numeric $arg) { echo $this->format($arg); } public function format(Argument $arg) { $format = is_float($arg->getValue()) ? '%.3f' : '%d'; return sprintf($format, $arg->getValue()); } } But this would imply repeating myself for each and every child of Output, and makes my objects harder to reuse. I understand why the Liskov principle exists, don't get me wrong, but I find it somewhat difficult to fathom why the signature of an abstract method in an abstract class has to be adhered to so much stricter than a non-abstract method. Could someone explain to me why I'm not allowed to hind at a child class, in a child class? The way I see it, the child class OutputNumeric is a specific use-case of Output, and thus might need a specific instance of Argument, namely Numeric. Is it really so wrong of me to write code like this?

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  • Architecture diagram of a computer virus

    - by Shiraz Bhaiji
    I am looking for an architecture diagram of a computer virus. Does anyone have a link to a good example? Edit Looks like I am getting hammered with downvotes. I agree that there is no single architecture for a virus. But somethings must be included for a program to be a virus. Example for components in the SAD: Replication method Trigger Payload Hosts targeted Vulnerabilities targeted Anti detection method

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