Search Results

Search found 11626 results on 466 pages for 'cross thread communicatio'.

Page 135/466 | < Previous Page | 131 132 133 134 135 136 137 138 139 140 141 142  | Next Page >

  • Setup basic proxypass in Apache

    - by Eric
    I have a web application that communicates to a web service deployed on the same server. The web app was written with Tibco General Interface and works well only when it is running locally on the development system. When I deploy the web app to the Apache server it fails with code 200 apparently due to cross domain data. I use Firefox as a browser. I have tried changing Internet Explorer to access cross domain data and it works however IE is not an option. Web application runs on 192.168.2.205 (port 80). Web service runs on 192.168.2.205:8040 I have tried a number of things with proxypass inside Apache with no luck.

    Read the article

  • How to configure maximum number of transport channels in WCF using basicHttpBinding?

    - by Hemant
    Consider following code which is essentially a WCF host: [ServiceContract (Namespace = "http://www.mightycalc.com")] interface ICalculator { [OperationContract] int Add (int aNum1, int aNum2); } [ServiceBehavior (InstanceContextMode = InstanceContextMode.PerCall)] class Calculator: ICalculator { public int Add (int aNum1, int aNum2) { Thread.Sleep (2000); //Simulate a lengthy operation return aNum1 + aNum2; } } class Program { static void Main (string[] args) { try { using (var serviceHost = new ServiceHost (typeof (Calculator))) { var httpBinding = new BasicHttpBinding (BasicHttpSecurityMode.None); serviceHost.AddServiceEndpoint (typeof (ICalculator), httpBinding, "http://172.16.9.191:2221/calc"); serviceHost.Open (); Console.WriteLine ("Service is running. ENJOY!!!"); Console.WriteLine ("Type 'stop' and hit enter to stop the service."); Console.ReadLine (); if (serviceHost.State == CommunicationState.Opened) serviceHost.Close (); } } catch (Exception e) { Console.WriteLine (e); Console.ReadLine (); } } } Also the WCF client program is: class Program { static int COUNT = 0; static Timer timer = null; static void Main (string[] args) { var threads = new Thread[10]; for (int i = 0; i < threads.Length; i++) { threads[i] = new Thread (Calculate); threads[i].Start (null); } timer = new Timer (o => Console.WriteLine ("Count: {0}", COUNT), null, 1000, 1000); Console.ReadLine (); timer.Dispose (); } static void Calculate (object state) { var c = new CalculatorClient ("BasicHttpBinding_ICalculator"); c.Open (); while (true) { try { var sum = c.Add (2, 3); Interlocked.Increment (ref COUNT); } catch (Exception ex) { Console.WriteLine ("Error on thread {0}: {1}", Thread.CurrentThread.Name, ex.GetType ()); break; } } c.Close (); } } Basically, I am creating 10 proxy clients and then repeatedly calling Add service method. Now if I run both applications and observe opened TCP connections using netstat, I find that: If both client and server are running on same machine, number of tcp connections are equal to number of proxy objects. It means all requests are being served in parallel. Which is good. If I run server on a separate machine, I observed that maximum 2 TCP connections are opened regardless of the number of proxy objects I create. Only 2 requests run in parallel. It hurts the processing speed badly. If I switch to net.tcp binding, everything works fine (a separate TCP connection for each proxy object even if they are running on different machines). I am very confused and unable to make the basicHttpBinding use more TCP connections. I know it is a long question, but please help!

    Read the article

  • clicktale.com alternative that works with https and ajax

    - by Alexey Ivanov
    I need to record user's actions on site for analytics purposes. The way clicktale.com doing it is just fine. But unfortunately it have problems with working over https and recording ajax events. Is there some service or script/library that I can host that can do this task? Non-free one's are ok to. Clarification: ClickTale function that I want to reproduce is recording of separate user sessions and their replay. So you can see video of all user's interactions with page: There he clicks first, which links opens, etc. Usually such services replay user's actions buy reproducing them with javascript (and here comes ajax problem: external sites can't use ajax because of cross-domain scripting). So I'm looking for a tool (possibly script that I host on site to allow cross-domain scripting) that can record ajax blocks actions.

    Read the article

  • How to produce precisely-timed tone and silence in C#

    - by Bob Denny
    I have a C# project that plays Morse code for RSS feeds. I write it using Managed DirectX, only to discover that Managed DirectX is old and deprecated. The task I have is to play pure sine wave bursts interspersed with silence periods (the code) which are precisely timed as to their duration. I need to be able to call a function which plays a pure tone for so many milliseconds, then Thread.Sleep() then play another, etc. At its fastest, the tones and spaces can be as short as 40ms. It's working quite well in Managed DirectX. To get the precisely timed tone I create 1 sec. of sine wave into a secondary buffer, then to play a tone of a certain duration I seek forward to within x milliseconds of the end of the buffer then play. I've tried System.Media.SoundPlayer. It's a loser because you have to Play(), Sleep(), then Stop() for arbitrary tone lengths. The result is a tone that is too long, variable by CPU load. It takes an indeterminate amount of time to actually stop the tone. I then embarked on a lengthy attempt to use NAudio 1.3. I ended up with a memory resident stream providing the tone data, and again seeking forward leaving the desired length of tone remaining in the stream, then playing. This worked OK on the DirectSoundOut class for a while (see below) but the WaveOut class quickly dies with an internal assert saying that buffers are still on the queue despite PlayerStopped = true. This is odd since I play to the end then put a wait of the same duration between the end of the tone and the start of the next. You'd think that 80ms after starting Play of a 40 ms tone that it wouldn't have buffers on the queue. DirectSoundOut works well for a while, but its problem is that for every tone burst Play() it spins off a separate thread. Eventually (5 min or so) it just stops working. You can see thread after thread after thread exiting in the Output window while running the project in VS2008 IDE. I don't create new objects during playing, I just Seek() the tone stream then call Play() over and over, so I don't think it's a problem with orphaned buffers/whatever piling up till it's choked. I'm out of patience on this one, so I'm asking in the hopes that someone here has faced a similar requirement and can steer me in a direction with a likely solution. Thanks in advance...

    Read the article

  • GCD and AppleEvents / NSOperationQueue and AppleScript

    - by mahal tertin
    As i understood, the threads provided by GCD do have a runloop but no source/port. Now i use some of methods that call AppleScripts thru AppleEvents inside an NSOperationQueue. And sometimes my app crashes with following stacktrace. my questions: Usage of AppleScript inside a NSInvocationOperation or NSBlockOperation Usage of AppleEvents inside GCD-Threads do i have to add a source / port to a runloop of a gcd-thread before using AppleEvents? do i have to add a source / port to a runloop of a gcd-thread before using [CATransaction commit]? do i have to add a source / port to a runloop of a gcd-thread before using [NSObject performSelectorAfterDelay...] ? if yes, how? can i simply call CFRunLoopRunInMode(kCFRunLoopDefaultMode, 5.0, false); /// or 30 or the defined timeout of appleevent? .. Thread 9: Dispatch queue: com.apple.root.default-priority 0 libSystem.B.dylib 0x00007fff88276e82 semaphore_wait_signal_trap 10 1 libSystem.B.dylib 0x00007fff8827c3cd pthread_mutex_lock 469 2 com.apple.applescript 0x000000011d3d461f AppleScriptComponent 50 3 com.apple.applescript 0x000000011d3edbcc AGenericCall::Delegate(ComponentInstanceRecord*) 46 4 com.apple.applescript 0x000000011d3ed520 AGenericManager::HandleOSACall(ComponentParameters*) 54 5 com.apple.applescript 0x000000011d3ed4b0 GenericComponent 219 6 com.apple.openscripting 0x00007fff8381c6da OSAExecuteEvent 63 7 com.apple.Foundation 0x00007fff86f320d8 -[NSAppleScript(NSPrivate) _executeAppleEvent:withMode:error:] 161 8 xxx 0x0000000100048af0 -[TCallScript callScript:withArrayOfParameters:] 480 9 xxx 0x0000000100048ffd -[TCallScript callHandler:withParameters:] 477 10 xxx 0x0000000100036032 -[ZFOpenWindowController getSafariItemForCurrentTabForWindow:] 66 11 xxx 0x00000001000346af -[ZFOpenWindowController refreshWindowList:] 1679 12 xxx 0x000000010003541c -[ZFOpenWindowController bringZFToForegroundZoomOut:orJustLinkFrontMost:toItem:] 2988 13 xxx 0x0000000100053556 __-[ZFSelectionTool openWithPreferredApplication:]_block_invoke_516 54 14 com.apple.Foundation 0x00007fff86ed87d9 -[NSBlockOperation main] 140 15 com.apple.Foundation 0x00007fff86ec906d -[__NSOperationInternal start] 681 16 com.apple.Foundation 0x00007fff86ec8d23 ____startOperations_block_invoke_2 99 17 libSystem.B.dylib 0x00007fff882b2ce8 _dispatch_call_block_and_release 15 18 libSystem.B.dylib 0x00007fff88291279 _dispatch_worker_thread2 231 19 libSystem.B.dylib 0x00007fff88290bb8 _pthread_wqthread 353 20 libSystem.B.dylib 0x00007fff88290a55 start_wqthread 13 ... Thread 11 Crashed: Dispatch queue: com.apple.root.default-priority 0 com.apple.applescript 0x000000011d40f658 BCHandleError() 182 1 com.apple.applescript 0x000000011d4059ca UASExecute1() 2546 2 com.apple.applescript 0x000000011d3dd1d5 ASExecuteEvent(AEDesc const*, unsigned int, int, unsigned int*) 695 3 ...ple.CoreServices.CarbonCore 0x00007fff85388e04 CallComponentFunction 28 4 com.apple.applescript 0x000000011d3d4cad AppleScriptComponent 1728 5 com.apple.applescript 0x000000011d3edbcc AGenericCall::Delegate(ComponentInstanceRecord*) 46 6 com.apple.applescript 0x000000011d3ed520 AGenericManager::HandleOSACall(ComponentParameters*) 54 7 com.apple.applescript 0x000000011d3ed4b0 GenericComponent 219 8 com.apple.openscripting 0x00007fff8381c6da OSAExecuteEvent 63 9 com.apple.Foundation 0x00007fff86f320d8 -[NSAppleScript(NSPrivate) _executeAppleEvent:withMode:error:] 161 10 xxx 0x0000000100048af0 -[TCallScript callScript:withArrayOfParameters:] 480 11 xxx 0x0000000100048ffd -[TCallScript callHandler:withParameters:] 477 12 xxx 0x0000000100035c67 -[ZFOpenWindowController getItemForAXDocumentOfFrontMostWindow] 119 13 xxx 0x00000001000359f1 -[ZFOpenWindowController getItemForFrontMostWindow:] 721 14 xxx 0x00000001000348ac -[ZFOpenWindowController bringZFToForegroundZoomOut:orJustLinkFrontMost:toItem:] 60 15 xxx 0x0000000100053556 __-[ZFSelectionTool openWithPreferredApplication:]_block_invoke_516 54 16 com.apple.Foundation 0x00007fff86ed87d9 -[NSBlockOperation main] 140 17 com.apple.Foundation 0x00007fff86ec906d -[__NSOperationInternal start] 681 18 com.apple.Foundation 0x00007fff86ec8d23 ____startOperations_block_invoke_2 99 19 libSystem.B.dylib 0x00007fff882b2ce8 _dispatch_call_block_and_release 15 20 libSystem.B.dylib 0x00007fff88291279 _dispatch_worker_thread2 231 21 libSystem.B.dylib 0x00007fff88290bb8 _pthread_wqthread 353 22 libSystem.B.dylib 0x00007fff88290a55 start_wqthread 13

    Read the article

  • Factors to consider when building an algorithm for gun recoil

    - by Nate Bross
    What would be a good algorithm for calculating the recoil of a shooting guns cross-hairs? What I've got now, is something like this: Define min/max recoil based on weapon size Generate random number of "delta" movement Apply random value to X, Y, or both of cross-hairs (only "up" on the Y axis) Multiply new delta based on time from the previous shot (more recoil for full-auto) What I'm worried about is that this feels rather predicable, what other factors should one take into account when building recoil? While I'd like it to be somewhat predictable, I'd also like to keep players on their toes. I'm thinking about increasing the min/max recoil values by a large amount (relatively) and adding a weighting, so large recoils will be more rare -- it seems like a lot of effort to go into something I felt would be simple. Maybe this is just something that needs to be fine-tuned with additional playtesting, and more playtesters? I think that it's important to note, that the recoil will be a large part of the game, and is a key factor in the game being fun/challenging or not.

    Read the article

  • Rotate sprite to face 3D camera

    - by omikun
    I am trying to rotate a sprite so it is always facing a 3D camera. shaders->setUniform("camera", gCamera.matrix()); glm::mat4 scale = glm::scale(glm::mat4(), glm::vec3(5e5, 5e5, 5e5)); glm::vec3 look = gCamera.position(); glm::vec3 right = glm::cross(gCamera.up(), look); glm::vec3 up = glm::cross(look, right); glm::mat4 newTransform = glm::lookAt(glm::vec3(0), gCamera.position(), up) * scale; shaders->setUniform("model", newTransform); In the vertex shader: gl_Position = camera * model * vec4(vert, 1); The object will track the camera if I move the camera up or down, but if I rotate the camera around it, it will rotate in the other direction so I end up seeing its front twice and its back twice as I rotate around it 360. What am I doing wrong?

    Read the article

  • Core-Data + AFNetworking + UI Updating (Responsiveness)

    - by Mustafa
    Here's the scenario: I'm writing a DownloadManager, that allows the user to download, pause, cancel, download all, and pause all. The DownloadManager is a singleton, and uses AFNetworking to download files. It has it's own private managed object context, so that user can freely use other parts of the application (by adding, editing, deleting) core-data objects. I have a core-data entity DownloadInfo that stores the download information i.e. fileURL, fileSize, bytesRead, etc. The DownloadManager updates the download progress in DownloadInfo (one for each file). I have a DownloadManagerViewController which uses NSFetchedResultsController to show the download status to the user. This download view controller is using the main managed object context. Now let's say that I have 20 files in the download queue. And let's say that only 3 concurrent downloads are allowed. The download manager should download the file, and show the download progress. Problem: The DownloadInfo objects are being updated by the DownloadManager at a very high rate. The DownloadManagerViewController (responsible for showing the download progress) is updating the list using NSFetchedResultsControllerDelegate methods. The result is that a lot is happening in the main queue and application has very poor responsiveness. How can I fix this? How can I make the application responsive, while showing the download progress? I don't know how else to communicate that the download status between DownloadManager and DownloadManagerViewController. Is there another/ a better way to do this? I don't want to use main managed object context in my DownloadManager, for reasons mentioned above. Note, that the DownloadManager is using AFNetworking which is handling the requests asynchronously, but eventually the DownloadInfo objects are updated in the main thread (as a result of the callback methods). Maybe there's a way to handle the downloads and status update operations in a background thread? but how? How will I communicate between the main thread and the background thread i.e. how will I tell the background thread to queue another file for download? Thanks.

    Read the article

  • How to produce precisely-timed tone and silence?

    - by Bob Denny
    I have a C# project that plays Morse code for RSS feeds. I write it using Managed DirectX, only to discover that Managed DirectX is old and deprecated. The task I have is to play pure sine wave bursts interspersed with silence periods (the code) which are precisely timed as to their duration. I need to be able to call a function which plays a pure tone for so many milliseconds, then Thread.Sleep() then play another, etc. At its fastest, the tones and spaces can be as short as 40ms. It's working quite well in Managed DirectX. To get the precisely timed tone I create 1 sec. of sine wave into a secondary buffer, then to play a tone of a certain duration I seek forward to within x milliseconds of the end of the buffer then play. I've tried System.Media.SoundPlayer. It's a loser because you have to Play(), Sleep(), then Stop() for arbitrary tone lengths. The result is a tone that is too long, variable by CPU load. It takes an indeterminate amount of time to actually stop the tone. I then embarked on a lengthy attempt to use NAudio 1.3. I ended up with a memory resident stream providing the tone data, and again seeking forward leaving the desired length of tone remaining in the stream, then playing. This worked OK on the DirectSoundOut class for a while (see below) but the WaveOut class quickly dies with an internal assert saying that buffers are still on the queue despite PlayerStopped = true. This is odd since I play to the end then put a wait of the same duration between the end of the tone and the start of the next. You'd think that 80ms after starting Play of a 40 ms tone that it wouldn't have buffers on the queue. DirectSoundOut works well for a while, but its problem is that for every tone burst Play() it spins off a separate thread. Eventually (5 min or so) it just stops working. You can see thread after thread after thread exiting in the Output window while running the project in VS2008 IDE. I don't create new objects during playing, I just Seek() the tone stream then call Play() over and over, so I don't think it's a problem with orphaned buffers/whatever piling up till it's choked. I'm out of patience on this one, so I'm asking in the hopes that someone here has faced a similar requirement and can steer me in a direction with a likely solution.

    Read the article

  • a problem in socks.h

    - by janathan
    i use this (http://www.codeproject.com/KB/IP/Socks.aspx) lib in my socket programing in c++ and copy the socks.h in include folder and write this code: include include include include include include "socks.h" define PORT 1001 // the port client will be connecting to define MAXDATASIZE 100 static void ReadThread(void* lp); int socketId; int main(int argc, char* argv[]) { const char temp[]="GET / HTTP/1.0\r\n\r\n"; CSocks cs; cs.SetVersion(SOCKS_VER4); cs.SetSocksPort(1080); cs.SetDestinationPort(1001); cs.SetDestinationAddress("192.168.11.97"); cs.SetSocksAddress("192.168.11.97"); //cs.SetVersion(SOCKS_VER5); //cs.SetSocksAddress("128.0.21.200"); socketId = cs.Connect(); // if failed if (cs.m_IsError) { printf( "\n%s", cs.GetLastErrorMessage()); getch(); return 0; } // send packet for requesting to a server if(socketId > 0) { send(socketId, temp, strlen(temp), 0); HANDLE ReadThreadID; // handle for read thread id HANDLE handle; // handle for thread handle handle = CreateThread ((LPSECURITY_ATTRIBUTES)NULL, // No security attributes. (DWORD)0, // Use same stack size. (LPTHREAD_START_ROUTINE)ReadThread, // Thread procedure. (LPVOID)(void*)NULL, // Parameter to pass. (DWORD)0, // Run immediately. (LPDWORD)&ReadThreadID); WaitForSingleObject(handle, INFINITE); } else { printf("\nSocks Server / Destination Server not started.."); } closesocket(socketId); getch(); return 0; } // Thread Proc for reading from server socket. static void ReadThread(void* lp) { int numbytes; char buf[MAXDATASIZE]; while(1) { if ((numbytes=recv(socketId, buf, MAXDATASIZE-1, 0)) == -1) { printf("\nServer / Socks Server has been closed Receive thread Closed\0"); break; } if (numbytes == 0) break; buf[numbytes] = '\0'; printf("Received: %s\r\n",buf); send(socketId,buf,strlen(buf),0); } } but when compile this i get an error . pls help me thanks

    Read the article

  • Hibernate save() and transaction rollback

    - by Marco
    Hi, In Hibernate when i save() an object in a transaction, and then i rollback it, the saved object still remains in the DB. It's strange because this issue doesn't happen with the update() or delete() method, just with save(). Here is the code i'm using: DbEntity dbEntity = getDbEntity(); HibernateUtil.beginTransaction(); Session session = HibernateUtil.getCurrentSession(); session.save(dbEntity); HibernateUtil.rollbackTransaction(); And here is the HibernateUtil class (just the involved functions, i guarantee the getSessionFactory() method works well - there is an Interceptor handler, but it doesn't matter now): private static final ThreadLocal<Session> threadSession = new ThreadLocal<Session>(); private static final ThreadLocal<Transaction> threadTransaction = new ThreadLocal<Transaction>(); /** * Retrieves the current Session local to the thread. * <p/> * If no Session is open, opens a new Session for the running thread. * * @return Session */ public static Session getCurrentSession() throws HibernateException { Session s = (Session) threadSession.get(); try { if (s == null) { log.debug("Opening new Session for this thread."); if (getInterceptor() != null) { log.debug("Using interceptor: " + getInterceptor().getClass()); s = getSessionFactory().openSession(getInterceptor()); } else { s = getSessionFactory().openSession(); } threadSession.set(s); } } catch (HibernateException ex) { throw new HibernateException(ex); } return s; } /** * Start a new database transaction. */ public static void beginTransaction() throws HibernateException { Transaction tx = (Transaction) threadTransaction.get(); try { if (tx == null) { log.debug("Starting new database transaction in this thread."); tx = getCurrentSession().beginTransaction(); threadTransaction.set(tx); } } catch (HibernateException ex) { throw new HibernateException(ex); } } /** * Rollback the database transaction. */ public static void rollbackTransaction() throws HibernateException { Transaction tx = (Transaction) threadTransaction.get(); try { threadTransaction.set(null); if ( tx != null && !tx.wasCommitted() && !tx.wasRolledBack() ) { log.debug("Tyring to rollback database transaction of this thread."); tx.rollback(); } } catch (HibernateException ex) { throw new HibernateException(ex); } finally { closeSession(); } } Thanks

    Read the article

  • Sharepoint 2010, People Picker (peoplepicker-searchadforests), 1 way Active Directory trust .... process monitor to the rescue!

    - by steve schofield
    If you run Sharepoint 2010 in one forest, users in another forest and a 1-way forest in-place.  There is some additional configuration needed in Sharepoint 2010.  I included links below that discuss the details.  My post is not to be in-depth how to setup, rather share a tidbit not discussed in documentation (not that I could find).  Thanks to a smart co-worker and process monitor, it was found there is a registry entry, the application pool needs READ access.  You can either manually grant permissions on the server or add registry permission in AD Group Policy.  Hope this helps. People Picker overview (SharePoint Server 2010)http://technet.microsoft.com/en-us/library/gg602068.aspx Configure People Picker (SharePoint Server 2010)http://technet.microsoft.com/en-us/library/gg602075(d=lightweight).aspx Peoplepicker-searchadforests: Stsadm property (Office SharePoint Server)http://technet.microsoft.com/en-us/library/cc263460.aspx Application Pool needs read accessMACHINE\SOFTWARE\Microsoft\Shared Tools\Web Server Extensions\14.0\Secure Multi Forest/Cross Forest People Pickerhttp://blogs.msdn.com/b/joelo/archive/2007/01/18/multi-forest-cross-forest-people-picker-peoplepicker-searchadcustomquery.aspx Process Monitorhttp://technet.microsoft.com/en-us/sysinternals/bb896645.aspx Steve SchofieldMicrosoft MVP - IIS

    Read the article

  • BindException/Too many file open while using HttpClient under load

    - by Langali
    I have got 1000 dedicated Java threads where each thread polls a corresponding url every one second. public class Poller { public static Node poll(Node node) { GetMethod method = null; try { HttpClient client = new HttpClient(new SimpleHttpConnectionManager(true)); ...... } catch (IOException ex) { ex.printStackTrace(); } finally { method.releaseConnection(); } } } The threads are run every one second: for (int i=0; i <1000; i++) { MyThread thread = threads.get(i) // threads is a static field if(thread.isAlive()) { // If the previous thread is still running, let it run. } else { thread.start(); } } The problem is if I run the job every one second I get random exceptions like these: java.net.BindException: Address already in use INFO httpclient.HttpMethodDirector: I/O exception (java.net.BindException) caught when processing request: Address already in use INFO httpclient.HttpMethodDirector: Retrying request But if I run the job every 2 seconds or more, everything runs fine. I even tried shutting down the instance of SimpleHttpConnectionManager() using shutDown() with no effect. If I do netstat, I see thousands of TCP connections in TIME_WAIT state, which means they are have been closed and are clearing up. So to limit the no of connections, I tried using a single instance of HttpClient and use it like this: public class MyHttpClientFactory { private static MyHttpClientFactory instance = new HttpClientFactory(); private MultiThreadedHttpConnectionManager connectionManager; private HttpClient client; private HttpClientFactory() { init(); } public static HttpClientFactory getInstance() { return instance; } public void init() { connectionManager = new MultiThreadedHttpConnectionManager(); HttpConnectionManagerParams managerParams = new HttpConnectionManagerParams(); managerParams.setMaxTotalConnections(1000); connectionManager.setParams(managerParams); client = new HttpClient(connectionManager); } public HttpClient getHttpClient() { if (client != null) { return client; } else { init(); return client; } } } However after running for exactly 2 hours, it starts throwing 'too many open files' and eventually cannot do anything at all. ERROR java.net.SocketException: Too many open files INFO httpclient.HttpMethodDirector: I/O exception (java.net.SocketException) caught when processing request: Too many open files INFO httpclient.HttpMethodDirector: Retrying request I should be able to increase the no of connections allowed and make it work, but I would just be prolonging the evil. Any idea what is the best practise to use HttpClient in a situation like above? Btw, I am still on HttpClient3.1.

    Read the article

  • Scala actors: receive vs react

    - by jqno
    Let me first say that I have quite a lot of Java experience, but have only recently become interested in functional languages. Recently I've started looking at Scala, which seems like a very nice language. However, I've been reading about Scala's Actor framework in Programming in Scala, and there's one thing I don't understand. In chapter 30.4 it says that using react instead of receive makes it possible to re-use threads, which is good for performance, since threads are expensive in the JVM. Does this mean that, as long as I remember to call react instead of receive, I can start as many Actors as I like? Before discovering Scala, I've been playing with Erlang, and the author of Programming Erlang boasts about spawning over 200,000 processes without breaking a sweat. I'd hate to do that with Java threads. What kind of limits am I looking at in Scala as compared to Erlang (and Java)? Also, how does this thread re-use work in Scala? Let's assume, for simplicity, that I have only one thread. Will all the actors that I start run sequentially in this thread, or will some sort of task-switching take place? For example, if I start two actors that ping-pong messages to each other, will I risk deadlock if they're started in the same thread? According to Programming in Scala, writing actors to use react is more difficult than with receive. This sounds plausible, since react doesn't return. However, the book goes on to show how you can put a react inside a loop using Actor.loop. As a result, you get loop { react { ... } } which, to me, seems pretty similar to while (true) { receive { ... } } which is used earlier in the book. Still, the book says that "in practice, programs will need at least a few receive's". So what am I missing here? What can receive do that react cannot, besides return? And why do I care? Finally, coming to the core of what I don't understand: the book keeps mentioning how using react makes it possible to discard the call stack to re-use the thread. How does that work? Why is it necessary to discard the call stack? And why can the call stack be discarded when a function terminates by throwing an exception (react), but not when it terminates by returning (receive)? I have the impression that Programming in Scala has been glossing over some of the key issues here, which is a shame, because otherwise it's a truly excellent book.

    Read the article

  • Application Development: Python or Java (or PHP)

    - by luckysmack
    I'm looking to get into application development, such as Facebook or Android apps and games. I am doing this for fun and to learn. Once my skills are to par I would like to have some side income from the apps, but I'm not banking on living off that (just so you know where I'm coming from and know what my end goals are). Currently I know and am familiar with PHP and frameworks such as cakephp and yii. However, I have been wanting to learn another language to broaden my horizons and to become a better developer. So I have narrowed it down to 2 languages. Python, and Java (I can already hear people cringing at the difference in the languages I have chosen, but I have some reasons). Python: closer to PHP that Java. Cross platformability. Also great as a general scripting language and has many file system level benefits that PHP does not. Cleaner syntax, readability, blah blah and the list goed on. Python will work great for cross platform apps and can be run on many OS's and is supported by Facebook for app development. But there is no support on Android (for full fledged apps). Java: a much stronger typed language, very robust community and corporate backing. Knowing Java is also good for personal marketability for enterprises, if you're into that. The main benefit here is that Java can write apps natively for Android and the apps can be ported for web versions to play on Facebook. So while I have seen many developers prefer Java over the two, Java has this significant advantage, where I can market my apps in both markets and in the future build more potential income. But like I said it is for fun. While money isn't the goal, it would still be nice. PHP: I'm putting this here because I know it already, and I'm sure a case could be made for it. It obviously works great for Facebook but like Python does not do so well on android. While it's mostly the realm of 'application development' that appeals to me, I do find Android apps fairly interesting and something that has a ton of potential to. But then again Facebook has a ton more users and the apps can also potentially be more immersive (desktop vs. mobile). So this is why I'm kinda stuck on what route to choose. Python for Facebook and web apps, with likely faster development to production times, or Java which can be developed for any of the platforms to make apps. Side note: I'm not really trying to get into 3D development, mostly 2D. And I also want to make an app with real-time play (websockets, etc). Someone mentioned node, js to me for that but Python seems to be more globally versatile for my goals. So, to anyone that does Facebook or Android development in either language: what do you suggest? Any input is valuable and I do appreciate it. And sorry for being long winded. EDIT: as mentioned in one of the answers, my primary goal is gaming. Although I do have some plans for non gaming apps such as general web based and desktop based ones. But gaming is my main goal with the possibility of income. EDIT: Another consideration could be Jython. Writing Python code which is converted into Java bytecode. This would allow the ability to do Android apps using Python. I could be wrong though, I'm still looking into it. Update 1-26-11: I recently acquired a new job which required I learn .NET using C#. Im sure some of you are cringing already but I really like the whole system and how it all works together between desktop and web development. But, as I am still interested in Python very much, and after some research I have decided I will learn Python as well as the IronPython implementation for .NET. But (again: I know...) since .NET is mostly a Windows thing and not as cross-compatible as I like, I will be learning Mono which is a cross platform implementation of .NET where I can use what I learn at work using C# and what I want to learn, Python/IronPython. So while learning and writing C#/.NET @ work I will be learning Python - Mono - Iron Python for what I want to do personally. And the benefit of them all being very closely related will help me out a lot, I think. What do you guys think? I almost feel like that should be another question, but there's not much of a question. Either way, you guys gave very helpful input.

    Read the article

  • Multiple vulnerabilities in Thunderbird

    - by RitwikGhoshal
    CVE DescriptionCVSSv2 Base ScoreComponentProduct and Resolution CVE-2012-1948 Denial of service (DoS) vulnerability 9.3 Thunderbird Solaris 10 SPARC: 145200-12 X86: 145201-12 CVE-2012-1950 Address spoofing vulnerability 6.4 CVE-2012-1951 Resource Management Errors vulnerability 10.0 CVE-2012-1952 Resource Management Errors vulnerability 9.3 CVE-2012-1953 Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability 9.3 CVE-2012-1954 Resource Management Errors vulnerability 10.0 CVE-2012-1955 Address spoofing vulnerability 6.8 CVE-2012-1957 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability 4.3 CVE-2012-1958 Resource Management Errors vulnerability 9.3 CVE-2012-1959 Permissions, Privileges, and Access Controls vulnerability 5.0 CVE-2012-1961 Improper Input Validation vulnerability 4.3 CVE-2012-1962 Resource Management Errors vulnerability 10.0 CVE-2012-1963 Permissions, Privileges, and Access Controls vulnerability 4.3 CVE-2012-1964 Clickjacking vulnerability 4.0 CVE-2012-1965 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability 4.3 CVE-2012-1966 Permissions, Privileges, and Access Controls vulnerability 4.3 CVE-2012-1967 Arbitrary code execution vulnerability 10.0 CVE-2012-1970 Denial of service (DoS) vulnerability 10.0 CVE-2012-1973 Resource Management Errors vulnerability 10.0 CVE-2012-3966 Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability 10.0 This notification describes vulnerabilities fixed in third-party components that are included in Oracle's product distributions.Information about vulnerabilities affecting Oracle products can be found on Oracle Critical Patch Updates and Security Alerts page.

    Read the article

  • Oracle Commerce Best Practices for the Communications Industry

    - by Michael Seback
      In today’s volatile economy, Communications Service Providers are challenged to offer a complete, cross-channel commerce experience. With Oracle Commerce solutions, CSPs can get closer to customers and gain valuable insight to maximize ROI across all commerce activities. Join us for a  live webcast on September 26th with featured speakers Raghavendra Ademane, Omni-Channel Commerce Consultant at Professional Access and Brenna Johnson, Product Manager, Oracle and learn how you can manage and deliver commerce experiences for Communications that engage customers and promote loyalty. The panelists will guide you through a number of topics including: Current Communications market trends, opportunities and challenges Introduction to the Oracle Commerce solution with case studies Demonstration of the solution for Communications with live Q&A Register today and learn how Oracle's latest innovations for Communications can help you increase online sales and enhance cross-channel commerce interactions.

    Read the article

  • Webinar: Oracle Commerce Best Practices for the Communications Industry

    - by Jeri Kelley
    In today’s volatile economy, Communications Service Providers are challenged to offer a complete, cross-channel commerce experience. With Oracle Commerce solutions, CSPs can get closer to customers and gain valuable insight to maximize ROI across all commerce activities. Join us for a  live webcast on September 26th with featured speakers Raghavendra Ademane, Omni-Channel Commerce Consultant at Professional Access and Brenna Johnson, Product Manager, Oracle and learn how you can manage and deliver commerce experiences for Communications that engage customers and promote loyalty. The panelists will guide you through a number of topics including: Current Communications market trends, opportunities and challenges Introduction to the Oracle Commerce solution with case studies Demonstration of the solution for Communications with live Q&A Register today and learn how Oracle's latest innovations for Communications can help you increase online sales and enhance cross-channel commerce interactions.

    Read the article

  • How the simples GUI countdown is supposed to work?

    - by Roman
    I am trying to write the simples GUI countdown. I found in Internet some code but it is already too fancy for me. I am trying to keep it as simple as possible. So, I just want to have a window saying "You have 10 second left". The number of second should decrease every second from 10 to 0. I wrote a code. And I think I am close to the working solution. But I still missing something. Could you pleas help me to find out what is wrong? Here is my code: import javax.swing.*; public class Countdown { static JLabel label; // Method which defines the appearance of the window. private static void showGUI() { JFrame frame = new JFrame("Simple Countdown"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JLabel label = new JLabel("Some Text"); frame.add(label); frame.pack(); frame.setVisible(true); } // Define a new thread in which the countdown is counting down. static Thread counter = new Thread() { public void run() { for (int i=10; i>0; i=i-1) { updateGUI(i,label); try {Thread.sleep(1000);} catch(InterruptedException e) {}; } } }; // A method which updates GUI (sets a new value of JLabel). private static void updateGUI(final int i, final JLabel label) { SwingUtilities.invokeLater(new Runnable(i,label) { public Runnable(int i, JLabel label) { this.i = i; this.label = label; } public void run() { label.setText("You have " + i + " seconds."); } }); } // The main method (entry point). public static void main(String[] args) { javax.swing.SwingUtilities.invokeLater(new Runnable() { public void run() { showGUI(); //counter.start(); } }); //counter.start(); } } And I have several concrete question about this code: Where should I place the counter.start();? (In my code I put it on 2 places. Which one is correct?) Why compiler complains about the constructor for Runnable? It says that I have an invalid method declaration and I need to specify the returned type. ADDED: I made the suggested corrections. And then I execute the code and get: Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at Worker.run(Worker.java:12) In the Worker.java in the line 12 I have: label.setText("You have " + i + " seconds.");.

    Read the article

  • Humble Bundle Gives You DRM-Free Games at Pay-What-You-Want Prices

    - by Jason Fitzpatrick
    The Humble Bundle is back–score cross-platform games at a pay-what-you-want price and even send the proceeds to charity in the process. Between now and April 2nd, score great independent games like Zen Bound 2 and Avadaon: The Black Fortress with a name-your-price deal courtesy of The Humble Bundle. You pay what you want and specify how you want the money divided among the developers and the Electronic Frontier Foundation/Child’s Play charities. Check out the video above to see the games included in the bundle. All games are cross-platform, available for Windows, Mac, Linux, and Android, and DRM-Free. The Humble Bundle The HTG Guide to Hiding Your Data in a TrueCrypt Hidden Volume Make Your Own Windows 8 Start Button with Zero Memory Usage Reader Request: How To Repair Blurry Photos

    Read the article

  • Are there efforts to build a collaboratively edited HTML/JS/DOM reference?

    - by Pekka
    W3Schools has a reputation of being incomplete, sometimes incorrect, and ridden with advertising; still, when looking to look up some things or link to documentation when answering a SO question, it still is the only handy cross-browser resource. There are other resources like the Mozilla Developer Network that is doing an increasingly great job documenting JavaScript, and the legendary and great Quirksmode. But they, as brilliant as they are, cover only parts of the areas I am talking about, and provide no community editing and quality control options. Is anybody aware of efforts to create a collaboratively edited, cross-browser HTML/CSS/JavaScript/DOM encyclopedia? If you will, I'm thinking of a challenger to W3Schools like SO was to Experts Exchange. (I thought this more suitable on Programmers than on SO proper - please correct me if I'm wrong.)

    Read the article

  • What is the best way, if possible, to send information from a Java PrintStream to a JTextPane?

    - by Daniel Reeves
    In Java, I have a package that translates XML metadata from one standard to another. This package is ultimately accessed through a single function and sends all of its output through a PrintStream object. The output sent is just a status of each file and whether or not it was translated. This is pretty fine and dandy if I'm just printing to System.out, but I'm actually wanting to print this to a JTextPane while it translates (kind of like a progress text box). It wouldn't be a big deal to just print the status after it was done translating the XML, but since there may be thousands of XML files, that's just not feasible. One thing that I've tried is to use a thread that takes all of the information from the PrintStream (which is attached to a ByteArrayOutputStream) and let it send any new information to the text pane. Unfortunately, this still sends the information all at once at the end of the translation. This does work correctly for System.out. Here's the code that does the translation and tries to show the output: public class ConverterGUI extends javax.swing.JFrame { boolean printToResultsBox = false; PrintStream printStream = null; ByteArrayOutputStream baos = null; private class ResultsPrinter implements Runnable { public ResultsPrinter() { baos = new ByteArrayOutputStream(); printStream = new PrintStream(baos); } public void run() { String tempString = ""; while (printToResultsBox) { try { if (!baos.toString().equals(tempString)) { tempString = baos.toString(); resultsBox.setText(tempString); } } catch (Exception ex) { } } } } ... ResultsPrinter rp = new ResultsPrinter(); Thread thread = new Thread(rp); thread.start(); // Do the translation. try { printToResultsBox = true; boolean success = false; TranslationEngine te = new TranslationEngine(); // fileOrFolderToConvert is a text box in the GUI. // linkNeeded and destinationFile are just parameters for the translation process. success = te.translate(fileOrFolderToConvert.getText(), linkNeeded, destinationFile, printStream); if (success) { printStream.println("File/folder translation was a success."); } resultsBox.setText(baos.toString()); } catch (Exception ex) { printStream.println("File translation failed."); } finally { printToResultsBox = false; } ... } Ultimately, this code prints out to the JTextPane just fine after all the translation is done but not during. Any suggestions? Do I need to change the PrintStream to something else?

    Read the article

< Previous Page | 131 132 133 134 135 136 137 138 139 140 141 142  | Next Page >