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  • Colorbox with bxslider not working

    - by Bill K
    Hello I am trying to use bxslider with colorbox. My implementation of bxslider is like an example listed here. The difference is that I want only the pagers to be shown. Also when the user clicks one pager I want colorbox to open and have next and previous buttons. The problem is that I cant group the images with colorbox and next and previous button is not shown! The following code uses the rel option but with this way colorbox doesnt event start. What I have tried till now is: HTML <div class="slider_mini" style="position:relative;bottom:0px;"> <div id="bx-pager"> <a data-slide-index="0" href="image.jpg" class="imgz"><img style="width:130px;height:104px;" src="image.jpg"/></a> <a data-slide-index="1" href="image2.jpg" class="imgz"><img style="width:130px;height:104px;" src="image2.jpg"/></a> <a data-slide-index="2" href="image3.jpg" class="imgz"><img style="width:130px;height:104px;" src="image3.jpg"/></a> </div> </div> SCRIPT <script type="text/javascript"> $(document).ready(function(){ $('.imgz').colorbox({rel:'imgz'}); $('.bxslider.two').bxSlider({ pagerCustom: '#bx-pager' }); $('#bx-pager').bxSlider({ slideWidth: 130, minSlides: 2, maxSlides: 3, moveSlides: 1, slideMargin: 10 }); }); </script> Not working Fiddle. Feedback: The problem was in live website that I was calling colorbox before bxslider. I put the call after bxslider's and it works. Thank you.

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  • Solving problems involving more complex data structures with CUDA

    - by Nils
    So I read a bit about CUDA and GPU programming. I noticed a few things such that access to global memory is slow (therefore shared memory should be used) and that the execution path of threads in a warp should not diverge. I also looked at the (dense) matrix multiplication example, described in the programmers manual and the nbody problem. And the trick with the implementation seems to be the same: Arrange the calculation in a grid (which it already is in case of the matrix mul); then subdivide the grid into smaller tiles; fetch the tiles into shared memory and let the threads calculate as long as possible, until it needs to reload data from the global memory into shared memory. In case of the nbody problem the calculation for each body-body interaction is exactly the same (page 682): bodyBodyInteraction(float4 bi, float4 bj, float3 ai) It takes two bodies and an acceleration vectors. The body vector has four components it's position and the weight. When reading the paper, the calculation is understood easily. But what is if we have a more complex object, with a dynamic data structure? For now just assume that we have an object (similar to the body object presented in the paper) which has a list of other objects attached and the number of objects attached is different in each thread. How could I implement that without having the execution paths of the threads to diverge? I'm also looking for literature which explains how different algorithms involving more complex data structures can be effectively implemented in CUDA.

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  • Any book on designing and implementing a CRPG engine?

    - by Fabzter
    Hi! First, let me tell you, I am not really interested in making my own rpg engine (at least not in the near future, hehe), but I do feel like I want to understand the internals of how a rpg engine works. Why? Well, because I like to read about programming and design, It keeps me motivated and excited, and because I know I will learn a lot, for, even when I have been programming for some years now, I never stop considering myself an ignorant... there are simply SO many things involving a game engine (specially rpg ones, like branching storylines, and items and economics!) I'm eager to know. I've been searching (and thus, finding) lots of info online, but it is never focused in what I'm interested (most of it talks about the mathematics and AI algorithms implementation, which I know quite well), which is the design of overall structure, patterns, scripting engine, decision engine... damn, so many things I can't even imagine, since I've never done any game programming. I hope you know have an idea of how I feel, and how I want to learn for the sake of learning, and why would I want you to tell me if you know if there exist books touching the topics that interest me the most.

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  • Good patterns for loose coupling in Java?

    - by Eye of Hell
    Hello. I'm new to java, and while reading documentation so far i can't find any good ways for programming with loose coupling between objects. For majority of languages i know (C++, C#, python, javascript) i can manage objects as having 'signals' (notification about something happens/something needed) and 'slots' (method that can be connected to signal and process notification/do some work). In all mentioned languages i can write something like this: Object1 = new Object1Class(); Object2 = new Object2Class(); Connect( Object1.ItemAdded, Object2.OnItemAdded ); Now if object1 calls/emits ItemAdded, the OnItemAdded method of Object2 will be called. Such loose coupling technique is often referred as 'delegates', 'signal-slot' or 'inversion of control'. Compared to interface pattern, technique mentioned don't need to group signals into some interfaces. Any object's methods can be connected to any delegate as long as signatures match ( C++Qt even extends this by allowing only partial signature match ). So i don't need to write additional interface code for each methods / groups of methods, provide default implementation for interface methods not used etc. And i can't see anything like this in Java :(. Maybe i'm looking a wrong way?

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  • How can I improve this design?

    - by klausbyskov
    Let's assume that our system can perform actions, and that an action requires some parameters to do its work. I have defined the following base class for all actions (simplified for your reading pleasure): public abstract class BaseBusinessAction<TActionParameters> : where TActionParameters : IActionParameters { protected BaseBusinessAction(TActionParameters actionParameters) { if (actionParameters == null) throw new ArgumentNullException("actionParameters"); this.Parameters = actionParameters; if (!ParametersAreValid()) throw new ArgumentException("Valid parameters must be supplied", "actionParameters"); } protected TActionParameters Parameters { get; private set; } protected abstract bool ParametersAreValid(); public void CommonMethod() { ... } } Only a concrete implementation of BaseBusinessAction knows how to validate that the parameters passed to it are valid, and therefore the ParametersAreValid is an abstract function. However, I want the base class constructor to enforce that the parameters passed are always valid, so I've added a call to ParametersAreValid to the constructor and I throw an exception when the function returns false. So far so good, right? Well, no. Code analysis is telling me to "not call overridable methods in constructors" which actually makes a lot of sense because when the base class's constructor is called the child class's constructor has not yet been called, and therefore the ParametersAreValid method may not have access to some critical member variable that the child class's constructor would set. So the question is this: How do I improve this design? Do I add a Func<bool, TActionParameters> parameter to the base class constructor? If I did: public class MyAction<MyParameters> { public MyAction(MyParameters actionParameters, bool something) : base(actionParameters, ValidateIt) { this.something = something; } private bool something; public static bool ValidateIt() { return something; } } This would work because ValidateIt is static, but I don't know... Is there a better way? Comments are very welcome.

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  • AJAX - querying a search engine and returning the number of results

    - by Moddy
    Right, so basically I need to query a selection of search engines in an AJAX app. As there is a number of different search engines - there's no search engine specific API I can use either. My main problem is getting the number of results returned by the search. So far, I have decided it is probably best to use a regexp from the returned search query HTML, and then convert the string of characters to an integer. However, this method just doesn't feel.. clean to me. It seems a bit rough around the edges and I think it could do with improving! I guess not being 100% confident with regular expressions doesn't help; but it just feels like it could be improved. Any ideas on how to implement this would be great cheers! It doesn't seem like that an exotic thing to do, so I was wondering if perhaps any of you guys have done this before and would have a few tips? Note: This is an AJAX app at the moment, but I may be re-writing this functionality in a different app soon - which won't be AJAX. I'm confident I can transfer any AJAX implementation to the other language though.

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  • Basic Subversion questions

    - by Epitaph
    I've just started using subversion, and have read the official documentation (svn book), cheat sheet and a couple of guides. I know how to install subversion (in linux), create a repository (svnadmin create), and import my Eclipse project into the repository (SVN import), view the repository files (using svn list). But I am unable to understand some of the other terminologies. For example, after importing my Eclipse project into the newly created repository I have made changes to my Eclipse project (more than 1 file). Now, how should I update the repository with this added files/changes made to my Eclipse project? The svn update command brings the changes from the repository into your working copy - which is the opposite of what I want i.e. bring the changes I made in my Eclipse project into the previously imported project in repository. If I am correct, you update the repository more often (as you keep extending your project implementation) than your current project (with update). Also, I do not understand when would you use svn merge. The svn book states it applies the differences between 2 sources to a working copy. Is there a scenario which would explain this? Finally, can I have more than 1 project checked into the repository? Or is it better to create a new repository for each project?

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  • Atomic Instructions and Variable Update visibility

    - by dsimcha
    On most common platforms (the most important being x86; I understand that some platforms have extremely difficult memory models that provide almost no guarantees useful for multithreading, but I don't care about rare counter-examples), is the following code safe? Thread 1: someVariable = doStuff(); atomicSet(stuffDoneFlag, 1); Thread 2: while(!atomicRead(stuffDoneFlag)) {} // Wait for stuffDoneFlag to be set. doMoreStuff(someVariable); Assuming standard, reasonable implementations of atomic ops: Is Thread 1's assignment to someVariable guaranteed to complete before atomicSet() is called? Is Thread 2 guaranteed to see the assignment to someVariable before calling doMoreStuff() provided it reads stuffDoneFlag atomically? Edits: The implementation of atomic ops I'm using contains the x86 LOCK instruction in each operation, if that helps. Assume stuffDoneFlag is properly cleared somehow. How isn't important. This is a very simplified example. I created it this way so that you wouldn't have to understand the whole context of the problem to answer it. I know it's not efficient.

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  • Why is python decode replacing more than the invalid bytes from an encoded string?

    - by dangra
    Trying to decode an invalid encoded utf-8 html page gives different results in python, firefox and chrome. The invalid encoded fragment from test page looks like 'PREFIX\xe3\xabSUFFIX' >>> fragment = 'PREFIX\xe3\xabSUFFIX' >>> fragment.decode('utf-8', 'strict') ... UnicodeDecodeError: 'utf8' codec can't decode bytes in position 6-8: invalid data What follows is the summary of replacement policies used to handle decoding errors by python, firefox and chrome. Note how the three differs, and specially how python builtin removes the valid S (plus the invalid sequence of bytes). by Python The builtin replace error handler replaces the invalid \xe3\xab plus the S from SUFFIX by U+FFFD >>> fragment.decode('utf-8', 'replace') u'PREFIX\ufffdUFFIX' >>> print _ PREFIX?UFFIX The python implementation builtin replace error handler looks like: >>> python_replace = lambda exc: (u'\ufffd', exc.end) As expected, trying this gives same result than builtin: >>> codecs.register_error('python_replace', python_replace) >>> fragment.decode('utf-8', 'python_replace') u'PREFIX\ufffdUFFIX' >>> print _ PREFIX?UFFIX by Firefox Firefox replaces each invalid byte by U+FFFD >>> firefox_replace = lambda exc: (u'\ufffd', exc.start+1) >>> codecs.register_error('firefox_replace', firefox_replace) >>> test_string.decode('utf-8', 'firefox_replace') u'PREFIX\ufffd\ufffdSUFFIX' >>> print _ PREFIX??SUFFIX by Chrome Chrome replaces each invalid sequence of bytes by U+FFFD >>> chrome_replace = lambda exc: (u'\ufffd', exc.end-1) >>> codecs.register_error('chrome_replace', chrome_replace) >>> fragment.decode('utf-8', 'chrome_replace') u'PREFIX\ufffdSUFFIX' >>> print _ PREFIX?SUFFIX The main question is why builtin replace error handler for str.decode is removing the S from SUFFIX. Also, is there any unicode's official recommended way for handling decoding replacements?

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  • Best approach for a multi-tab ASP.NET AJAX control?

    - by NovaJoe
    Looking for some implementation advice: I have a page that has a 3-tab ajaxToolkit:TabContainer. The purpose of the page is to expose a calculator that has two basic inputs: geo-location and date. The three tabs are labeled "City and State", "Postal Code", and "GPS Coordinates". The layout of each tab container is the same for each tab, with the exception of the location section; the location section changes because each type of location has different inputs. For example, to specify city/state, there will be three fields: city, country, and state (country and state will use cascading drop-down lists). But Postal code requires only one field (which will validate via regular expression for allowed countries). See the example design mockup: So, what I WOULD LIKE to do (in order to minimize duplicate code), is to have a common control that contains the layout and structure of the calculator without specifying anything about the location section. Then, I'd like to be able to pull in each of the unique location controls based on what tab is selected. The tab structure exists at the page level, not in a control. Any advice? I was looking at templated controls (see MSDN article here), but I'm not convinced that it's the right solution. If I HAVE to create three separate controls with similar layouts and common elements, then that's what I have to do. But REALLY, I'd prefer a more elegant, inheritance-based solution. Any advice would be greatly appreciated. Thanks.

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  • Is using SharePoint as a intranet/extranet portal a good idea?

    - by Rob
    I work for a fortune 500 company in IT and we have developed many systems/applications to do a variety of things. We are in need of some commonality of these applications and a better portal/dashboard/landing page for these applications. So, our customers and employees would log into this portal and see all the "things" that they can do which then link to their own application. This could maybe just iframe in each application inside of this portal to keep brand and navigation consistency. We are trying to decide whether to use SharePoint 2007 or 2010 for this or develop a portal/dashboard of sorts in house. We would like this portal to look and feel very branded to our needs and really not even feel like its using SharePoint (if needed). An example is to provide our own Menu control that drives the navigation if needed. Does anyone have any pros/cons for using SharePoint in such a way? Any advice on implementation (e.g. use 2010, much easier to customize design than 2007, etc)?

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  • Kerberos and/or other authentication systems - One time logon for all PHP scripts

    - by devviedev
    I'm managing a set of web apps, almost exclusively written in PHP, and would like to find an authentication platform to build a role-based authorization system on top of. Also, I'd like the authentication system to be extensible to use for, for example, system services (SSH, etc.) Here are some of the main characteristics I'm looking for, in order of importance: Easy PHP implementation (storing/reading easily roles, etc.). Redundant, if possible. If an auth system goes down everyone is not locked out. Has clients for Windows and Mac. Easy web-based administration (adding/removing users/roles, changing passwords). If not, I can build an administration system without too much effort. One-time log on. I'd also like, when an auth token is issued, to store the user's IP address and use that to authorize the user for some non web-based applications. For that reason, I'd like a desktop client to issue the token and revoke tokens when, for example, the user becomes idle at their workstation. I'm thinking Kerberos might be a solution, but what are other options?

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  • How to avoid using this in a constructor

    - by Paralife
    I have this situation: interface MessageListener { void onMessageReceipt(Message message); } class MessageReceiver { MessageListener listener; public MessageReceiver(MessageListener listener, other arguments...) { this.listener = listener; } loop() { Message message = nextMessage(); listener.onMessageReceipt(message); } } and I want to avoid the following pattern: (Using the this in the Client constructor) class Client implements MessageListener { MessageReceiver receiver; MessageSender sender; public Client(...) { receiver = new MessageReceiver(this, other arguments...); sender = new Sender(...); } . . . @Override public void onMessageReceipt(Message message) { if(Message.isGood()) sender.send("Congrtulations"); else sender.send("Boooooooo"); } } The reason why i need the above functionality is because i want to call the sender inside the onMessageReceipt() function, for example to send a reply. But I dont want to pass the sender into a listener, so the only way I can think of is containing the sender in a class that implements the listener, hence the above resulting Client implementation. Is there a way to achive this without the use of 'this' in the constructor? It feels bizare and i dont like it, since i am passing myself to an object(MessageReceiver) before I am fully constructed. On the other hand, the MessageReceiver is not passed from outside, it is constructed inside, but does this 'purifies' the bizarre pattern? I am seeking for an alternative or an assurance of some kind that this is safe, or situations on which it might backfire on me.

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  • Behavior of retained property while holder is retained

    - by Aurélien Vallée
    Hello everyone, I am a beginner ObjectiveC programmer, coming from the C++ world. I find it very difficult to understand the memory management offered by NSObject :/ Say I have the following class: @interface User : NSObject { NSString* name; } @property (nonatomic,retain) NSString* name; - (id) initWithName: (NSString*) theName; - (void) release; @end @implementation User @synthesize name - (id) initWithName: (NSString*) theName { if ( self = [super init] ) { [self setName:theName]; } return self; } - (void) release { [name release]; [super release]; } @end No considering the following code, I can't understand the retain count results: NSString* name = [[NSString alloc] initWithCString:/*C string from sqlite3*/]; // (1) name retainCount = 1 User* user = [[User alloc] initWithName:name]; // (2) name retainCount = 2 [whateverMutableArray addObject:user]; // (3) name retainCount = 2 [user release]; // (4) name retainCount = 1 [name release]; // (5) name retainCount = 0 At (4), the retain count of name decreased from 2 to 1. But that's not correct, there is still the instance of user inside the array that points to name ! The retain count of a variable should only decrease when the retain count of a referring variable is 0, that is, when it is dealloced, not released.

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  • Spring and hibernate.cfg.xml

    - by Steve Kuo
    How do I get Spring to load Hibernate's properties from hibernate.cfg.xml? We're using Spring and JPA (with Hibernate as the implementation). Spring's applicationContext.xml specifies the JPA dialect and Hibernate properties: <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean"> <property name="jpaDialect"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" /> </property> <property name="jpaProperties"> <props> <prop key="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</prop> </props> </property> </bean> In this configuration, Spring is reading all the Hibernate properties via applicationContext.xml . When I create a hibernate.cfg.xml (located at the root of my classpath, the same level as META-INF), Hibernate doesn't read it at all (it's completely ignored). What I'm trying to do is configure Hibernate second level cache by inserting the cache properties in hibernate.cfg.xml: <cache usage="transactional|read-write|nonstrict-read-write|read-only" region="RegionName" include="all|non-lazy" />

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  • Blocking on DBCP connection pool (open and close connnection). Is database connection pooling in OpenEJB pluggable?

    - by topchef
    We use OpenEJB on Tomcat (used to run on JBoss, Weblogic, etc.). While running load tests we experience significant performance problems with handling JMS messages (queues). Problem was localized to blocking on database connection pool getting or releasing connection to the pool. Blocking prevented concurrent MDB instances (threads) from running hence performance suffered 10-fold and worse. The same code used to run on application servers (with their respective connection pool implementations) with no blocking at all. Example of thread blocked: Name: JMS Resource Adapter-worker-23 State: BLOCKED on org.apache.commons.pool.impl.GenericObjectPool@1ea6b4a owned by: JMS Resource Adapter-worker-19 Total blocked: 18,426 Total waited: 0 Stack trace: org.apache.commons.pool.impl.GenericObjectPool.returnObject(GenericObjectPool.java:916) org.apache.commons.dbcp.PoolableConnection.close(PoolableConnection.java:91) - locked org.apache.commons.dbcp.PoolableConnection@1bcba8 org.apache.commons.dbcp.managed.ManagedConnection.close(ManagedConnection.java:147) com.xxxxx.persistence.DbHelper.closeConnection(DbHelper.java:290) .... Couple of questions. I am almost certain that some transactional attributes and properties contribute to this blocking, but MDBs are defined as non-transactional (we use both annotations and ejb-jar.xml). Some EJBs do use container-managed transactions though (and we can observe blocking there as well). Are there any DBCP configurations that may fix blocking? Is DBCP connection pool implementation replaceable in OpenEJB? How easy (difficult) to replace it with another library? Just in case this is how we define data source in OpenEJB (openejb.xml): <Resource id="MyDataSource" type="DataSource"> JdbcDriver oracle.jdbc.driver.OracleDriver JdbcUrl ${oracle.jdbc} UserName ${oracle.user} Password ${oracle.password} JtaManaged true InitialSize 5 MaxActive 30 ValidationQuery SELECT 1 FROM DUAL TestOnBorrow true </Resource>

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  • Problem with SQLite related nUnit-tests after upgrade to VS2010 and Re#5

    - by stiank81
    After converting to Visual Studio 2010 with ReSharper5 some of my unit tests started failing. More specifically this applies to all unit tests that use NHibernate with SQLite. The problem seem to be related to SQLite somehow. The unit tests that does not involve NHibernate and SQLite are still running fine. The exception is as follows: NHibernate.HibernateException : Could not create the driver from NHibernate.Driver.SQLite20Driver, NHibernate, Version=2.1.2.4000, Culture=neutral, PublicKeyToken=aa95f207798dfdb4. ----> System.Reflection.TargetInvocationException : Exception has been thrown by the target of an invocation. ----> NHibernate.HibernateException : The IDbCommand and IDbConnection implementation in the assembly System.Data.SQLite could not be found. Ensure that the assembly System.Data.SQLite is located in the application directory or in the Global Assembly Cache. If the assembly is in the GAC, use <qualifyAssembly/> element in the application configuration file to specify the full name of the assembly. TearDown : System.NullReferenceException : Object reference not set to an instance of an object. The exception is the NullReferenceException on TearDown when cleaning up NHibernate objects that wasn't successfully created, but the problem seem to be related to SQLite somehow. I run my unit tests through ReSharper, but I get the same exception when running them directly through the NUnit.exe application. However, running them through the x86 variant (NUnit-x86.exe) all tests run fine. Can it be related to some mixing of 64bit and 32bit dlls? It still runs fine through VS2008 + ReSharper4.5. Note that the target framework of my projects still is .NET3.5. Anyone seen this problem before?

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  • How to select a rectangle from List<Rectangle[]> with Linq

    - by dboarman
    I have a list of DrawObject[]. Each DrawObject has a Rectangle property. Here is my event: List<Canvas.DrawObject[]> matrix; void Control_MouseMove ( object sender, MouseEventArgs e ) { IEnumerable<Canvas.DrawObject> tile = Enumerable.Range( 0, matrix.Capacity - 1) .Where(row => Enumerable.Range(0, matrix[row].Length -1) .Where(column => this[column, row].Rectangle.Contains(e.Location))) .????; } I am not sure exactly what my final select command should be in place of the "????". Also, I was getting an error: cannot convert IEnumerable to bool. I've read several questions about performing a linq query on a list of arrays, but I can't quite get what is going wrong with this. Any help? Edit Apologies for not being clear in my intentions with the implementation. I intend to select the DrawObject that currently contains the mouse location.

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  • How to make a Global Array?

    - by Wayfarer
    So, I read this post, and it's pretty much exactly what I was looking for. However... it doesn't work. I guess I'm not going to go with the singleton object, but rather making the array in either a Global.h file, or insert it into the _Prefix file. Both times I do that though, I get the error: Expected specifier-qualifier-list before 'static' and it doesn't work. So... I'm not sure how to get it to work, I can remove extern and it works, but I feel like I need that to make it a constant. The end goal is to have this Mutable Array be accessible from any object or any file in my project. Help would be appreciated! This is the code for my Globals.h file: #import <Foundation/Foundation.h> @interface Globals : NSObject { static extern NSMutableArray * myGlobalArray; } @end I don't think I need anything in the implementation file. If I were to put that in the prefix file, the error was the same.

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  • How to map different UI views in a RESTful web application?

    - by MicE
    Hello, I'm designing a web application, which will support both standard UIs (accessed via browsers) and a RESTful API (an XML/JSON-based web service). User agents will be able to differentiate between these by using different values in the Accept HTTP header. The RESTful API will use the following URI structure (example for an "article" resource): GET /article/ - gets a list of articles POST /article/ - adds a new article PUT /article/{id} - updates an existing article based on {id} DELETE /article/{id} - deletes an existing article based on {id} The UI part of the application will however need to support multiple views, for example: a standard resource view a view for submitting a new resource a view for editing an existing resource a view for deleting an existing resource (i.e. display delete confirmation) Note that the latter three views are still accessed via GET, even though they are processed via overloaded POST. Possible solution: Introduce additional parameters (keywords) into URIs which would identify individual views - i.e. on top of the above, the application would support the following URIs (but only for Content-Type: text/html): GET /article/add - displays a form for adding a new article (fetched via GET, processed via POST) GET /article/123 - displays article 123 in "view" mode (fetched via GET) GET /article/123/edit - displays article 123 in "edit" mode (fetched via GET, processed via PUT overloaded as POST) GET /article/123/delete - displays "delete" confirmation for article 123 (fetched via GET, processed via DELETE overloaded as POST) A better implementation of the above might be to put the add/edit/delete keywords into a GET parameter - since they do not change the resource we're working with, it might be better to keep the base URI same for all of them. My question is: How would you map the above URI structure to UIs served to the regular user, considering that there can be several views per each resource, please? Do you agree with the possible solution detailed above, or would you recommend a different approach based on your experience? NB: we've already implemented an application which consists of a standalone RESTful API and a standalone web application. I'm currently looking into options for future projects where these two would be merged together (i.e. in order to reduce overhead). Thank you, M.

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  • What is the right approach to checksumming UDP packets

    - by mr.b
    I'm building UDP server application in C#. I've come across a packet checksum problem. As you probably know, each packet should carry some simple way of telling receiver if packet data is intact. Now, UDP already has 2-byte checksum as part of header, which is optional, at least in IPv4 world. Alternative method is to have custom checksum as part of data section in each packet, and to verify it on receiver. My question boils down to: is it better to rely on (optional) checksum in UDP packet header, or to make a custom checksum implementation as part of packet data section? Perhaps the right answer depends on circumstances (as usual), so one circumstance here is that, even though code is written and developed in .NET on Windows, it might have to run under platform-independent Mono.NET, so eventual solution should be compatible with other platforms. I believe that custom checksum algorithm would be easily portable, but I'm not so sure about the first one. Any thoughts? Also, shouts about packet checksumming in general are welcome.

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  • Silverlight - how to render image from non-visible data bound user control?

    - by MagicMax
    Hello! I have such situation - I'd like to build timeline control. So I have UserControl and ItemsControl on it (every row represents some person). The ItemsControl contains another ItemsControl as ItemsControl.ItemTemplate - it shows e.g. events for the person arranged by event's date. So it looks as some kind of grid with dates as a column headers and e.g. peoples as row headers. ........................|.2010.01.01.....2010.01.02.....2010.01.03 Adam Smith....|......[some event#1].....[some event#2]...... John Dow.......|...[some event#3].....[some event#4]......... I can have a lot of persons (ItemsControl #1 - 100-200 items) and a lot of events occured by some day (1-10-30 events per person in one day) the problem is that when user scrolls ItemsControl #1/#2 it happened toooo sloooooowwww due to a lot of elements should be rendered in one time (as I have e.g. a bit of text boxes and other elements in description of particular event) Question #1 - how can I improve it? May be somebody knows better way to build such user control? I have to mention that I'm using custom Virtual panel, based on some custom Virtual panel implementation found somewhere in internet... Question #2 - I'd like to make image with help of WriteableBitmap and render data bound control to image and to show image instead of a lot of elements. Problem is that I'm trying to render invisible data bound control (created in code behind) and it has actualWidth/Height equals to zero (so nothing rendered). How can I solve it? Thank you very much for you help!

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  • Why does my ActivePerl program report 'Sorry. Ran out of threads'?

    - by Zaid
    Tom Christiansen's example code (à la perlthrtut) is a recursive, threaded implementation of finding and printing all prime numbers between 3 and 1000. Below is a mildly adapted version of the script #!/usr/bin/perl # adapted from prime-pthread, courtesy of Tom Christiansen use strict; use warnings; use threads; use Thread::Queue; sub check_prime { my ($upstream,$cur_prime) = @_; my $child; my $downstream = Thread::Queue->new; while (my $num = $upstream->dequeue) { next unless ($num % $cur_prime); if ($child) { $downstream->enqueue($num); } else { $child = threads->create(\&check_prime, $downstream, $num); if ($child) { print "This is thread ",$child->tid,". Found prime: $num\n"; } else { warn "Sorry. Ran out of threads.\n"; last; } } } if ($child) { $downstream->enqueue(undef); $child->join; } } my $stream = Thread::Queue->new(3..shift,undef); check_prime($stream,2); When run on my machine (under ActiveState & Win32), the code was capable of spawning only 118 threads (last prime number found: 653) before terminating with a 'Sorry. Ran out of threads' warning. In trying to figure out why I was limited to the number of threads I could create, I replaced the use threads; line with use threads (stack_size => 1);. The resultant code happily dealt with churning out 2000+ threads. Can anyone explain this behavior?

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  • SerializationException with custom GenericIdentiy?

    - by MunkiPhD
    I'm trying to implement my own GenericIdentity implementation but keep receiving the following error when it attempts to load the views (I'm using asp.net MVC): System.Runtime.Serialization.SerializationException was unhandled by user code Message="Type is not resolved for member 'OpenIDExtendedIdentity,Training.Web, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'." Source="WebDev.WebHost" I've ended up with the following class: [Serializable] public class OpenIDExtendedIdentity : GenericIdentity { private string _nickName; private int _userId; public OpenIDExtendedIdentity(String name, string nickName, int userId) : base(name, "OpenID") { _nickName = nickName; _userId = userId; } public string NickName { get { return _nickName; } } public int UserID { get { return _userId; } } } In my Global.asax I read a cookie's serialized value into a memory stream and then use that to create my OpenIDExtendedIdentity object. I ended up with this attempt at a solution after countless tries of various sorts. It works correctly up until the point where it attempts to render the views. What I'm essentially attempting to achieve is the ability to do the following (While using the default Role manager from asp.net): User.Identity.UserID User.Identity.NickName ... etc. I've listed some of the sources I've read in my attempt to get this resolved. Some people have reported a Cassini error, but it seems like others have had success implementing this type of custom functionality - thus a boggling of my mind. http://forums.asp.net/p/32497/161775.aspx http://ondotnet.com/pub/a/dotnet/2004/02/02/effectiveformsauth.html http://social.msdn.microsoft.com/Forums/en-US/netfxremoting/thread/e6767ae2-dfbf-445b-9139-93735f1a0f72

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  • Resolving Circular References for Objects Implementing ISerializable

    - by Chris
    I'm writing my own IFormatter implementation and I cannot think of a way to resolve circular references between two types that both implement ISerializable. Here's the usual pattern: [Serializable] class Foo : ISerializable { private Bar m_bar; public Foo(Bar bar) { m_bar = bar; m_bar.Foo = this; } public Bar Bar { get { return m_bar; } } protected Foo(SerializationInfo info, StreamingContext context) { m_bar = (Bar)info.GetValue("1", typeof(Bar)); } public void GetObjectData(SerializationInfo info, StreamingContext context) { info.AddValue("1", m_bar); } } [Serializable] class Bar : ISerializable { private Foo m_foo; public Foo Foo { get { return m_foo; } set { m_foo = value; } } public Bar() { } protected Bar(SerializationInfo info, StreamingContext context) { m_foo = (Foo)info.GetValue("1", typeof(Foo)); } public void GetObjectData(SerializationInfo info, StreamingContext context) { info.AddValue("1", m_foo); } } I then do this: Bar b = new Bar(); Foo f = new Foo(b); bool equal = ReferenceEquals(b, b.Foo.Bar); // true // Serialise and deserialise b equal = ReferenceEquals(b, b.Foo.Bar); If I use an out-of-the-box BinaryFormatter to serialise and deserialise b, the above test for reference-equality returns true as one would expect. But I cannot conceive of a way to achieve this in my custom IFormatter. In a non-ISerializable situation I can simply revisit "pending" object fields using reflection once the target references have been resolved. But for objects implementing ISerializable it is not possible to inject new data using SerializationInfo. Can anyone point me in the right direction?

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