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  • Do I need Response.End() in ASP.Net 2.0

    - by Hamish Grubijan
    Hi, I am just starting with ASP.Net. I copied a ex-co-worker's code (from .Net 1.1 era) and it has a Response.End(); in case of an error. There is also a: catch (Exception ex) { Response.Write(ex.Message); Response.End(); } at the end of Page_Load(object sender, System.EventArgs e) which always appends "Thread was aborted." or something like that at the end. I suspect that this worked differently before, or the error conditions were not tested very well. Anyhow, I was able to stop using Response.End(); in case when I do not like the GET parameters, and use return; instead. It seemed to do the right think in a simple case. Is this Ok in general? There are some problems with the code I copied, but I do not want to do a rewrite; I just want to get it running first and find wrinkles later. The Response.End(); caused a mental block for me, however, so I want to figure it out. I want to keep the catch all clause just in case, at least for now. I could also end the method with: catch (System.Threading.ThreadAbortException) { Response.End(); } catch (Exception ex) { Response.Write(ex.Message); Response.End(); } but that just seems extremely stupid, once you think about all of the exceptions being generated. Please give me a few words of wisdom. Feel free to ask if something is not clear. Thanks! P.S. Ex-coworker was not fired and is a good coder - one more reason to reuse his example.

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  • Laggy interface with NSSearchField hooked up to an NSArrayController via bindings

    - by Simone Manganelli
    So I've got an NSSearchField hooked up directly to an NSArrayController via bindings, attached to the filterPredicate, so that without any code, the user can just type in the NSSearchField and filter the list of objects in the NSArrayController presented to him in the interface (an NSCollectionView, to be specific). The NSSearchField is hooked up to provide live searching, so that the NSCollectionView is filtered instantly as the user types, not after waiting for a short period for the user to stop typing. However, the problem is that this makes the interface really laggy. Typing is delayed significantly, by 0.5-1 seconds, and it seems like the NSCollectionView is trying to animate each and every rearrangement of items for each portion of the search string that the user enters. What I'd like is for the searching to be live, but the typing in the search field to be fluid, and the results to filter as fast as possible. Is there a way to do this via bindings, or will I need to put in some custom code that triggers the filterPredicate on a separate thread? (Note that I've got a custom sorting algorithm set up on the NSArrayController, and removing it seems to help a bit with the laggyness, but not completely.)

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  • How can I work out what events are being waited for with WinDBG in a kernel debug session

    - by Benj
    I'm a complete WinDbg newbie and I've been trying to debug a WindowsXP problem that a customer has sent me where our software and some third party software prevent windows from logging off. I've reproduced the problem and have verified that only when our software and the customers software are both installed (although not necessarily running at logoff) does the log off problem occur. I've observed that WM_ENDSESSION messages are not reaching the running windows when the user tries to log off and I know that the third party software uses a kernel driver. I've been looking at the processes in WinDbg and I know that csrss.exe would normally send all the windows a WM_ENDSESSION message. When I ran: !process 82356020 6 To look at csrss.exe's stack I can see: WARNING: Frame IP not in any known module. Following frames may be wrong. 00000000 00000000 00000000 00000000 00000000 0x7c90e514 THREAD 8246d998 Cid 0248.02a0 Teb: 7ffd7000 Win32Thread: e1627008 WAIT: (WrUserRequest) UserMode Non-Alertable 8243d9f0 SynchronizationEvent 81fe0390 SynchronizationEvent Not impersonating DeviceMap e1004450 Owning Process 82356020 Image: csrss.exe Attached Process N/A Image: N/A Wait Start TickCount 1813 Ticks: 20748 (0:00:05:24.187) Context Switch Count 3 LargeStack UserTime 00:00:00.000 KernelTime 00:00:00.000 Start Address 0x75b67cdf Stack Init f80bd000 Current f80bc9c8 Base f80bd000 Limit f80ba000 Call 0 Priority 14 BasePriority 13 PriorityDecrement 0 DecrementCount 0 Kernel stack not resident. ChildEBP RetAddr Args to Child f80bc9e0 80500ce6 00000000 8246d998 804f9af2 nt!KiSwapContext+0x2e (FPO: [Uses EBP] [0,0,4]) f80bc9ec 804f9af2 804f986e e1627008 00000000 nt!KiSwapThread+0x46 (FPO: [0,0,0]) f80bca24 bf80a4a3 00000002 82475218 00000001 nt!KeWaitForMultipleObjects+0x284 (FPO: [Non-Fpo]) f80bca5c bf88c0a6 00000001 82475218 00000000 win32k!xxxMsgWaitForMultipleObjects+0xb0 (FPO: [Non-Fpo]) f80bcd30 bf87507d bf9ac0a0 00000001 f80bcd54 win32k!xxxDesktopThread+0x339 (FPO: [Non-Fpo]) f80bcd40 bf8010fd bf9ac0a0 f80bcd64 00bcfff4 win32k!xxxCreateSystemThreads+0x6a (FPO: [Non-Fpo]) f80bcd54 8053d648 00000000 00000022 00000000 win32k!NtUserCallOneParam+0x23 (FPO: [Non-Fpo]) f80bcd54 7c90e514 00000000 00000022 00000000 nt!KiFastCallEntry+0xf8 (FPO: [0,0] TrapFrame @ f80bcd64) This waitForMultipleObjects looks interesting because I'm wondering if csrss.exe is waiting on some event which isn't arriving to allow the logoff. Can anyone tell me how I might find out what event it's waiting for anything else I might do to further investigate the problem?

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  • Different Scala Actor Implementations Overview

    - by Stefan K.
    I'm trying to find the 'right' actor implementation for my thesis. I realized there is a bunch of them and it's a bit confusing to pick one. Personally I'm especially interested in remote actors, but I guess a complete overview would be helpful to many others. This is a pretty general question, so feel free to answer just for the implementation you know about. I know about the following Scala Actor implementations (SAI). Please add the missing ones. Scala 2.7 (difference to) Scala 2.8 Akka (http://www.akkasource.org/) Lift (http://liftweb.net/) Scalaz (http://code.google.com/p/scalaz/) What are the target use-cases for these SAIs (lightweight vs. "heavy" enterprise framework)? do they support remote actors? What shortcomings do remote actors have in the SAIs? How is their performace? How active is there community? How easy are they to get started? How good is the documentation? How easy are they to extend? How stable are they? Which projects are using them? What are their shortcomings? What are their design principles? Are they thread based or event based (receive/ react) or both? Nested receiveS hotswapping the Actor’s message loop

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  • Our GUI Situation

    - by shawn-harrison
    These days, any decent Windows desktop application must perform well and look good under the following conditions: 1) XP and Vista and Windows 7. 2) 32 bit and 64 bit. 3) With and without Themes. 4) With and without Aero. 5) At 96 and 120 and perhaps custom DPIs. 6) One or more monitors (screens). 7) Each OS has it's own preferred Font. Oh My! What is a lowly little Windows desktop application developer to do :(. I'm hoping to get a thread started with suggestions on how to deal with this Gui dilemma. First off, I'm on Delphi 7. a) Does Delphi 2010 bring anything new to the table to help with this situation? b) Should we pick an aftermarket component suite and rely on them to solve all these problems? c) Should we go with an aftermarket skinning engine? d) Perhaps a more html type gui is the way to go. Can we make a relatively complex gui app with html that doesn't require using a browser? (prefer to keep it form based) e) Should we just knuckle down and code through each one of these scenarios and quit bitching about it? f) And finally, how in the world are we supposed to test all these conditions? thanks, shawnH

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  • Trying to set PC clock programmatically just before Daylight Saving Time ends

    - by Moe Sisko
    To reproduce : 1) Add Microsoft.VisualBasic assembly to your project reference 2) Change PC timezone to : (GMT+10:00) Canberra, Melbourne, Sydney . Ensure PC is set to automatically adjust clock for daylight savings time. (For this timezone, daylight savings time ends at 3am on 4 Apr 2010.) 3) add following code : public void SetNewDateTime(DateTime dt) { Microsoft.VisualBasic.DateAndTime.Today = dt; // ignores time component Microsoft.VisualBasic.DateAndTime.TimeOfDay = dt; // ignores date component } private void button1_Click(object sender, EventArgs e) { DateTime dt = new DateTime(2010, 4, 5, 5, 0, 0); // XX SetNewDateTime(dt); // XX System.Threading.Thread.Sleep(500); DateTime dt2 = new DateTime(2010, 4, 4, 1, 0, 0); SetNewDateTime(dt2); } 4) When button 1 is clicked, the PC clock eventually shows 2am, whereas 1 am was expected. (If code marked at "XX" is removed, the clock sometimes shows the correct time of 1 am). Any idea what is happening ? (Or is there a more reliable way of setting the PC clock from C# code ?) TIA.

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  • Python: How can I use Twisted as the transport for SUDS?

    - by jathanism
    I have a project that is based on Twisted used to communicate with network devices and I am adding support for a new vendor (Citrix NetScaler) whose API is SOAP. Unfortunately the support for SOAP in Twisted still relies on SOAPpy, which is badly out of date. In fact as of this question (I just checked), twisted.web.soap itself hasn't even been updated in 21 months! I would like to ask if anyone has any experience they would be willing to share with utilizing Twisted's superb asynchronous transport functionality with SUDS. It seems like plugging in a custom Twisted transport would be a natural fit in SUDS' Client.options.transport, I'm just having a hard time wrapping my head around it. I did come up with a way to call the SOAP method with SUDS asynchronously by utilizing twisted.internet.threads.deferToThread(), but this feels like a hack to me. Here is an example of what I've done, to give you an idea: # netscaler is a module I wrote using suds to interface with NetScaler SOAP # Source: http://bitbucket.org/jathanism/netscaler-api/src import netscaler import os import sys from twisted.internet import reactor, defer, threads # netscaler.API is the class that sets up the suds.client.Client object host = 'netscaler.local' username = password = 'nsroot' wsdl_url = 'file://' + os.path.join(os.getcwd(), 'NSUserAdmin.wsdl') api = netscaler.API(host, username=username, password=password, wsdl_url=wsdl_url) results = [] errors = [] def handleResult(result): print '\tgot result: %s' % (result,) results.append(result) def handleError(err): sys.stderr.write('\tgot failure: %s' % (err,)) errors.append(err) # this converts the api.login() call to a Twisted thread. # api.login() should return True and is is equivalent to: # api.service.login(username=self.username, password=self.password) deferred = threads.deferToThread(api.login) deferred.addCallbacks(handleResult, handleError) reactor.run() This works as expected and defers return of the api.login() call until it is complete, instead of blocking. But as I said, it doesn't feel right. Thanks in advance for any help, guidance, feedback, criticism, insults, or total solutions.

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  • Logback: What would cause DEBUG - WARN to append to file but NOT ERROR?

    - by Zombies
    I am running a Java program from Eclipe, and I am using the logback console plugin. I can see the ERROR level statements being appended to console (as well as all of the others). But for some reason my file, which is correctly recieving new DEBUG-WARN statements, is NOT recieving the ERROR level ones. Here is my logback.xml: <consolePlugin /> <appender name="FILE" class="ch.qos.logback.core.FileAppender"> <file>logs/main.log</file> <layout class="ch.qos.logback.classic.PatternLayout"> <Pattern>%date %level [%thread] %logger{10} [%file:%line] %msg%n</Pattern> </layout> </appender> <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"> <layout class="ch.qos.logback.classic.PatternLayout"> <Pattern>%msg%n</Pattern> </layout> </appender> <logger name="WebsiteChecker"> <appender-ref ref="FILE" /> </logger> <root> <level value="debug" /> <!--<appender-ref ref="STDOUT" />--> <appender-ref ref="FILE" /> </root> </configuration>

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  • Synchronizing Access to a member of the ASP.NET session

    - by Sam
    I'm building a Javascript application and eash user has an individual UserSession. The application makes a bunch of Ajax calls. Each Ajax call needs access to a single UserSession object for the user. Each Ajax call needs a UserSession object. Data in the UserSession object is unique to each user. Originally, during each Ajax call I would create a new UserSession object and it's data members were stored in the ASP.NET Session. However, I found that the UserSession object was being instantiated a lot. To minimize the construction of the UserSession object, I wrapped it in a Singleton pattern and sychronized access to it. I believe that the synchronization is happening application wide, however I only need it to happen per user. I saw a post here that says the ASP.NET cache is synchronized, however the time between creating the object and inserting it into the cache another Thread could start construction it's another object and insert it into the cache. Here is the way I'm currently synchronizing access to the object. Is there a better way than using "lock"... should be be locking on the HttpContext.Session object? private static object SessionLock = new object(); public static WebSession GetSession { get { lock (SessionLock) { try { var context = HttpContext.Current; WebSession result = null; if (context.Session["MySession"] == null) { result = new WebSession(context); context.Session["MySession"] = result; } else { result = (WebSession)context.Session["MySession"]; } return result; } catch (Exception ex) { ex.Handle(); return null; } } } }

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  • Multiple Concurrent Postbacks when using UpdatePanels

    - by d4nt
    Here's an example app that I built to demonstrate my problem. A single aspx page with the following on it: <form id="form1" runat="server"> <asp:ScriptManager runat="server" /> <asp:Button runat="server" ID="btnGo" Text="Go" OnClick="btnGo_Click" /> <asp:UpdatePanel runat="server"> <ContentTemplate> <asp:TextBox runat="server" ID="txtVal1" /> </ContentTemplate> </asp:UpdatePanel> </form> Then, in code behind, we have the following: protected void btnGo_Click(object sender, EventArgs e) { Thread.Sleep(5000); Debug.WriteLine(string.Format("{0}: {1}", DateTime.Now.ToString("HH:MM:ss.fffffff"), txtVal1.Text)); txtVal1.Text = ""; } If you run this and click on the "Go" button multiple times you will see multiple debug statements on the "Output" window showing that multiple requests have been processed. This appears to contradict the documented behaviour of update panels (i.e. If you make a request while one is processing, the first requests gets terminated and the current one is processed). Anyway, the point is I want to fix it. The obvious option would be to use Javascript to disable the button after the first press, but that strikes me as hard to maintain, we potentially have the same issue on a lot of screens it could be easily broken if someone renames a button. Do you have any suggestions? Perhaps there is something I could do in BeginRequest in Global.asax to detect a duplicate request? Is there some setting or feature on the UpdatePanel to stop it doing this, or maybe something in the AjaxControlToolkit that will prevent it?

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  • How can I see which shared folders my program has access to?

    - by Kasper Hansen
    My program needs to read and write to folders on other machines that might be in another domain. So I used the System.Runtime.InteropServices to add shared folders. This worked fine when it was hard coded in the main menu of my windows service. But since then something went wrong and I don't know if it is a coding error or configuration error. What is the scope of a shared folder? If a thread in my program adds a shared folder, can the entire local machine see it? Is there a way to view what shared folders has been added? Or is there a way to see when a folder is added? [DllImport("NetApi32.dll", SetLastError = true, CharSet = CharSet.Unicode)] internal static extern System.UInt32 NetUseAdd(string UncServerName, int Level, ref USE_INFO_2 Buf, out uint ParmError); [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] internal struct USE_INFO_2 { internal LPWSTR ui2_local; internal LPWSTR ui2_remote; internal LPWSTR ui2_password; internal DWORD ui2_status; internal DWORD ui2_asg_type; internal DWORD ui2_refcount; internal DWORD ui2_usecount; internal LPWSTR ui2_username; internal LPWSTR ui2_domainname; } private void AddSharedFolder(string name, string domain, string username, string password) { if (name == null || domain == null || username == null || password == null) return; USE_INFO_2 useInfo = new USE_INFO_2(); useInfo.ui2_remote = name; useInfo.ui2_password = password; useInfo.ui2_asg_type = 0; //disk drive useInfo.ui2_usecount = 1; useInfo.ui2_username = username; useInfo.ui2_domainname = domain; uint paramErrorIndex; uint returnCode = NetUseAdd(String.Empty, 2, ref useInfo, out paramErrorIndex); if (returnCode != 0) { throw new Win32Exception((int)returnCode); } }

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  • NoClassDefFoundError without any class name

    - by Safder
    Hello, I am trying to run a java task from ant. I am trying to run the "org.apache.tools.ant.launch.Launcher" class. I keep on getting the "NoClassDefFoundError" without any class name being specified. I am also getting a "ClassNotFoundException" along with that displaying a message "Could not find the main class: . Program will exit". Here's a snippet of the error [java] Exception in thread "main" java.lang.NoClassDefFoundError: [java] Caused by: java.lang.ClassNotFoundException: [java] at java.net.URLClassLoader$1.run(URLClassLoader.java:200) [java] at java.security.AccessController.doPrivileged(Native Method) [java] at java.net.URLClassLoader.findClass(URLClassLoader.java:188) [java] at java.lang.ClassLoader.loadClass(ClassLoader.java:307) [java] at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) [java] at java.lang.ClassLoader.loadClass(ClassLoader.java:252) [java] at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320) [java] Could not find the main class: . Program will exit. [java] Java Result: 1 Now I am trying to run an ant class from an ant jar and i specifiy the classpath where this class file resides using the "classpathref" attribute, however I still get this message. I checked the ant jar to check the Manifest and the "main" class is specified properly (it's "org.apache.tools.ant.launch.Launcher") . I have exhausted all my resources. Please help ! ! ! ps: My environment is Eclipse on Ubuntu 9.04

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  • Risking the exception anti-pattern.. with some modifications

    - by Sridhar Iyer
    Lets say that I have a library which runs 24x7 on certain machines. Even if the code is rock solid, a hardware fault can sooner or later trigger an exception. I would like to have some sort of failsafe in position for events like this. One approach would be to write wrapper functions that encapsulate each api a: returnCode=DEFAULT; try { returnCode=libraryAPI1(); } catch(...) { returnCode=BAD; } return returnCode; The caller of the library then restarts the whole thread, reinitializes the module if the returnCode is bad. Things CAN go horribly wrong. E.g. if the try block(or libraryAPI1()) had: func1(); char *x=malloc(1000); func2(); if func2() throws an exception, x will never be freed. On a similar vein, file corruption is a possible outcome. Could you please tell me what other things can possibly go wrong in this scenario?

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  • How do I design a Wizard-based system with SoC in mind?

    - by Erik Forbes
    I'm building a Windows Forms system (in C# if it matters to anyone) that provides an application automation service. As this application is targeted at users who are not computer savvy, I've decided to break up the functions of the application into various tasks, and provide these tasks via a wizard UI. I'd like to avoid coupling the views and view engine (from which the Wizard will be built) to the automation engine. The problem I'm having is that the automation engine, which runs on a separate thread while it does its thing, needs to report status information back to the user, as well as listen for cancel or pause events from the user. Since I don't want the view engine or the automation engine to rely on each other, I'm having a hard time figuring out how to provide for this information conduit. Any insights into this issue I'm having would be greatly appreciated. I've been wracking my brain for a couple weeks now on this point, and I really don't want to give up and just couple everything together. If anyone needs additional details to help come up with some sort of idea please let me know and I'll be happy to provide them.

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  • JUnit: checking if a void method gets called

    - by nkr1pt
    I have a very simple filewatcher class which checks every 2 seconds if a file has changed and if so, the onChange method (void) is called. Is there an easy way to check ik the onChange method is getting called in a unit test? code: public class PropertyFileWatcher extends TimerTask { private long timeStamp; private File file; public PropertyFileWatcher(File file) { this.file = file; this.timeStamp = file.lastModified(); } public final void run() { long timeStamp = file.lastModified(); if (this.timeStamp != timeStamp) { this.timeStamp = timeStamp; onChange(file); } } protected void onChange(File file) { System.out.println("Property file has changed"); } } @Test public void testPropertyFileWatcher() throws Exception { File file = new File("testfile"); file.createNewFile(); PropertyFileWatcher propertyFileWatcher = new PropertyFileWatcher(file); Timer timer = new Timer(); timer.schedule(propertyFileWatcher, 2000); FileWriter fw = new FileWriter(file); fw.write("blah"); fw.close(); Thread.sleep(8000); // check if propertyFileWatcher.onChange was called file.delete(); }

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  • When using Clipboard, Toolkit and Transferable, I get an error objecting to image width and height

    - by Mike King
    When I run the following code it triggers an error message. The error message is shown below the code. What code changes, or changes to the image file, are needed to fix this error? Help will be appreciated. import java.awt.*; import java.awt.datatransfer.*; public class LoadToClipboard { public static void main( String [] args ) { Toolkit tolkit = Toolkit.getDefaultToolkit(); Clipboard clip = tolkit.getSystemClipboard(); clip.setContents( new ImageSelection( tolkit.getImage("StackOverflowLogo.png")) , null ); } } class ImageSelection implements Transferable { private Image image; public ImageSelection(Image image) { this.image = image; } // Returns supported flavors public DataFlavor[] getTransferDataFlavors() { return new DataFlavor[]{DataFlavor.imageFlavor}; } // Returns true if flavor is supported public boolean isDataFlavorSupported(DataFlavor flavor) { return DataFlavor.imageFlavor.equals(flavor); } // Returns image public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException { if (!DataFlavor.imageFlavor.equals(flavor)) { throw new UnsupportedFlavorException(flavor); } return image; } } Exception in thread "main" java.lang.IllegalArgumentException: Width (-1) and height (-1) cannot be <= 0 at java.awt.image.DirectColorModel.createCompatibleWritableRaster(DirectColorModel.java:999) at sun.awt.datatransfer.DataTransferer.imageToStandardBytes(DataTransferer.java:1994) at sun.awt.windows.WDataTransferer.imageToPlatformBytes(WDataTransferer.java:267) at sun.awt.datatransfer.DataTransferer.translateTransferable(DataTransferer.java:1123) at sun.awt.windows.WDataTransferer.translateTransferable(WDataTransferer.java:163) at sun.awt.windows.WClipboard.setContentsNative(WClipboard.java:73) at sun.awt.datatransfer.SunClipboard.setContents(SunClipboard.java:93) at automateSignature.LoadToClipboard.main(LoadToClipboard.java:8) I have tried to find a place in the code where width and height can be specified, but have not succeeded. I also examined the properties of the jpg file and the w and h are specified.enter code here

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  • JMF microphone volume controller

    - by TacB0sS
    How to obtain the Microphone volume controller in JMF? this is what I have: I tried this implementation concept of yours, but I keep getting a null from the first volume processor when I try to get the stream, here is how I do it: // the device is the media device specifically audio Processor processorForVolume = Manager.createProcessor(device.getLocator()); // wait until configured ProcessorStates newState = new ProcessorStateListener(Processor.Configured).waitForProcessorState(processorForVolume); System.out.println("volumeProcessorState: "+newState); // setting the content descriptor to null - read in another thread this allows to get the gain control processorForVolume.setContentDescriptor(null); // set the track control format to one supported by the device and the track control. // I didn't match it to an RTP allowed format, but I don't think this has anything to do with it... TrackControl[] trackControls = processorForVolume.getTrackControls(); if (trackControls.length == 0) throw new MC_Exception("No track controls where found for this device:", new Object[]{device}); for (TrackControl control : trackControls) trackManipulator.manipulateTrackControls(control); // wait until the processor is realized newState = new ProcessorStateListener(Controller.Realized).waitForProcessorState(processorForVolume); System.out.println("volumeProcessorState: "+newState); // receives the gain control micVolumeController = processorForVolume.getGainControl(); // cannot get the output stream to process further... any suggestions? processor = Manager.createProcessor(processorForVolume.getDataOutput()); new ProcessorStateListener(Processor.Configured).waitForProcessorState(processor); processor.setContentDescriptor(DeviceCapturingManager.RAW_RTP); new ProcessorStateListener(Controller.Realized).waitForProcessorState(processor); this is the output It generates: volumeProcessorState: Configured format set to track control - com.sun.media.ProcessEngine$ProcTControl@1627c16: LINEAR, 48000.0 Hz, 16-bit, Stereo, LittleEndian, Signed volumeProcessorState: Realized and the data output from the processor is Null. I should make clear that when the content descriptor != null I do get an output stream but not the volume controller, and the when it is null I get the controller, but no stream. I try to connect to an audio microphone device Adam.

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  • Java semaphore to syncronize printing to screen

    - by Travis Griswald
    I'm currently stuck on a bit of homework and was wondering if anyone could help - I have to use semaphores in java to syncronize printing letters from 2 threads - one printing "A" and one printing "B". I cannot print out more than 2 of the same character in a row, so output should look like AABABABABABBABABABABAABBAABBABABA At the moment I have 3 semaphores, a binary mutex set to 1, and a counting semaphore, and my thread classes look something like this - public void run() { while (true) { Time.delay(RandomGenerator.integer(0,20)); Semaphores.mutex.down (); System.out.println (produce()); if (printCount > 1) { printCount = 0; Semaphores.mutex.up (); Semaphores.printB.up(); } } } public String produce() { printCount++; return "A"; } public void run() { while (true) { Time.delay(RandomGenerator.integer(0,20)); Semaphores.mutex.down (); System.out.println (produce()); if (printCount > 1) { printCount = 0; Semaphores.mutex.up (); Semaphores.printA.up(); } } } public String produce() { printCount++; return "B"; } Yet whatever I try it either deadlocks, or it seems to be working only printing 2 in a row at most, but always seems to print 3 in a row every now and again! Any help is much appreciated, not looking code or anything just a few pointers if possible :)

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  • What are the most time consuming checks performed by .NET when executing a managed appplication?

    - by ltorje
    I've developed a .NET based Windows service that uses part managed (C#) and unmanaged code (C/C++ libraries). In some domain environments (e.g. Win 2k3 32bit server inside domain abc.com) sometimes the service takes more than 30 seconds to start (especially on OS restart), thus failing to start the service. I suspect that it has something to do with enterprise level security but I do not know for sure. http://msdn.microsoft.com/en-us/library/aa720255%28VS.71%29.aspx I've tried the following without success: - delay loading references by moving the using directives as far as possible from the servicebase implementation (especially the xml namespace - know to cause delays in loading) - delay loading and configuring log4net - precompiling the code by using ngen - delaying the start of the worker thread - add/remove manifest + decencies set inside - sign/unsign the binaries - use the configuration settings (there are a lot of settings and the scope level for all is set to application ) as later as possible - add all dependencies to GAC I didn't tried yet to add security demands for the class that has the Main method implemented. I didn't tries to implement my own configuration loader because after inspecting the autogenerated code, I've noticed that the setting class is a singletone and it gets its instance on call. By completely removing the log4net dependency it worked, but this is not an option. When the network card is disabled the service starts immediately. Any suggestions/comments/solution you have would be most welcomed.

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  • boost::asio::async_resolve Problem

    - by Moo-Juice
    Hi All, I'm in the process of constructing a Socket class that uses boost::asio. To start with, I made a connect method that took a host and a port and resolved it to an IP address. This worked well, so I decided to look in to async_resolve. However, my callback always gets an error code of 995 (using the same destination host/port as when it worked synchronously). code: Function that starts the resolution: // resolve a host asynchronously template<typename ResolveHandler> void resolveHost(const String& _host, Port _port, ResolveHandler _handler) const { boost::asio::ip::tcp::endpoint ret; boost::asio::ip::tcp::resolver::query query(_host, boost::lexical_cast<std::string>(_port)); boost::asio::ip::tcp::resolver r(m_IOService); r.async_resolve(query, _handler); }; // eo resolveHost Code that calls this function: void Socket::connect(const String& _host, Port _port) { // Anon function for resolution of the host-name and asynchronous calling of the above auto anonResolve = [this](const boost::system::error_code& _errorCode, boost::asio::ip::tcp::resolver_iterator _epIt) { // raise event onResolve.raise(SocketResolveEventArgs(*this, !_errorCode ? (*_epIt).host_name() : String(""), _errorCode)); // perform connect, calling back to anonymous function if(!_errorCode) connect(*_epIt); }; // Resolve the host calling back to anonymous function Root::instance().resolveHost(_host, _port, anonResolve); }; // eo connect The message() function of the error_code is: The I/O operation has been aborted because of either a thread exit or an application request And my main.cpp looks like this: int _tmain(int argc, _TCHAR* argv[]) { morse::Root root; TextSocket s; s.connect("somehost.com", 1234); while(true) { root.performIO(); // calls io_service::run_one() } return 0; } Thanks in advance!

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  • Java Random Slowdowns on Mac OS cont'd

    - by javajustice
    I asked this question a few weeks ago, but I'm still having the problem and I have some new hints. The original question is here: http://stackoverflow.com/questions/1651887/java-random-slowdowns-on-mac-os Basically, I have a java application that splits a job into independent pieces and runs them in separate threads. The threads have no synchronization or shared memory items. The only resources they do share are data files on the hard disk, with each thread having an open file channel. Most of the time it runs very fast, but occasionally it will run very slow for no apparent reason. If I attach a CPU profiler to it, then it will start running quickly again. If I take a CPU snapshot, it says its spending most of its time in "self time" in a function that doesn't do anything except check a few (unshared unsynchronized) booleans. I don't know how this could be accurate because 1, it makes no sense, and 2, attaching the profiler seems to knock the threads out of whatever mode they're in and fix the problem. Also, regardless of whether it runs fast or slow, it always finishes and gives the same output, and it never dips in total cpu usage (in this case ~1500%), implying that the threads aren't getting blocked. I have tried different garbage collectors, different sizings the parts of the memory space, writing data output to non-raid drives, and putting all data output in threads separate the main worker threads. Does anyone have any idea what kind of problem this could be? Could it be the operating system (OS X 10.6.2) ? I have not been able to duplicate it on a windows machine, but I don't have one with a similar hardware configuration.

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  • Windows Server TCP Client application in c# Stops working after a while

    - by user1692494
    I am developping an application in C# Net framework 2.0. It is basicly a service application with a tcp client class. Class for Tcp Client Part public TelnetConnection(string Hostname, int Port) { host = Hostname; prt = Port; try { tcpSocket = new TcpClient(Hostname, Port); } catch (Exception e) { //Console.WriteLine(e.Message); } } The application is connecting to the server and revieves update's and more information. It works for about 20 minutes then stops recieving information from the server. -- Server side Client is still connected and the client side its still connected but stops receiving information from the server. I've been searching Stack Overflow and Google but no luck. try { if (!tcpSocket.Connected) return null; StringBuilder sb = new StringBuilder(); do { Parse(sb); System.Threading.Thread.Sleep(TimeOutMs); } while (tcpSocket.Available > 0); return sb.ToString(); } Application works perfect when it runs as console application but when running as service. It just stops.

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  • No unique bean of type [javax.persistence.EntityManagerFactory] is defined: expected single bean but found 0

    - by user659580
    Can someone tell me what's wrong with my config? I'm overly frustrated and I've been loosing my hair on this. Any pointer will be welcome. Thanks Persistence.xml <?xml version="1.0" encoding="UTF-8"?> <persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"> <persistence-unit name="myPersistenceUnit" transaction-type="JTA"> <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider> <jta-data-source>jdbc/oracle</jta-data-source> <class>com.myproject.domain.UserAccount</class> <properties> <property name="eclipselink.logging.level" value="FINE"/> <property name="eclipselink.jdbc.batch-writing" value="JDBC" /> <property name="eclipselink.target-database" value="Oracle10g"/> <property name="eclipselink.cache.type.default" value="NONE"/> <!--Integrate EclipseLink with JTA in Glassfish--> <property name="eclipselink.target-server" value="SunAS9"/> <property name="eclipselink.cache.size.default" value="0"/> <property name="eclipselink.cache.shared.default" value="false"/> </properties> </persistence-unit> </persistence> Web.xml <?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0"> <display-name>MyProject</display-name> <persistence-unit-ref> <persistence-unit-ref-name>persistence/myPersistenceUnit</persistence-unit-ref-name> <persistence-unit-name>myPersistenceUnit</persistence-unit-name> </persistence-unit-ref> <servlet> <servlet-name>mvc-dispatcher</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>mvc-dispatcher</servlet-name> <url-pattern>*.htm</url-pattern> </servlet-mapping> <context-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/mvc-dispatcher-servlet.xml</param-value> </context-param> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> </web-app> applicationContext.xml <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:jee="http://www.springframework.org/schema/jee" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee.xsd" default-autowire="byName"> <tx:annotation-driven/> <tx:jta-transaction-manager/> <jee:jndi-lookup id="entityManagerFactory" jndi-name="persistence/myPersistenceUnit"/> <bean class="org.springframework.beans.factory.annotation.RequiredAnnotationBeanPostProcessor"/> <bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/> <!-- enables interpretation of the @PersistenceUnit/@PersistenceContext annotations providing convenient access to EntityManagerFactory/EntityManager --> <bean class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor"/> </beans> mvc-dispatcher-servlet.xml <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> <!-- DispatcherServlet Context: defines this servlet's request-processing infrastructure --> <tx:annotation-driven /> <tx:jta-transaction-manager /> <context:component-scan base-package="com.myProject" /> <context:annotation-config /> <!-- Enables the Spring MVC @Controller programming model --> <mvc:annotation-driven /> <mvc:default-servlet-handler /> <bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" /> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" /> <!-- Location Tiles config --> <bean id="tilesConfigurer" class="org.springframework.web.servlet.view.tiles2.TilesConfigurer"> <property name="definitions"> <list> <value>/WEB-INF/tiles-defs.xml</value> </list> </property> </bean> <!-- Resolves views selected for rendering by Tiles --> <bean id="tilesViewResolver" class="org.springframework.web.servlet.view.UrlBasedViewResolver" p:viewClass="org.springframework.web.servlet.view.tiles2.TilesView" /> <!-- Resolves views selected for rendering by @Controllers to .jsp resources in the /WEB-INF/views directory --> <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix"> <value>/WEB-INF/pages/</value> </property> <property name="suffix"> <value>.jsp</value> </property> </bean> <bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource"> <property name="basename" value="/WEB-INF/messages" /> <property name="cacheSeconds" value="0"/> </bean> <bean id="validator" class="org.springframework.validation.beanvalidation.LocalValidatorFactoryBean" /> </beans> UserAccountDAO.java @Repository public class UserAccountDAO implements IUserAccountDAO { private EntityManager entityManager; @PersistenceContext public void setEntityManager(EntityManager entityManager) { this.entityManager = entityManager; } @Override @Transactional(readOnly = true, propagation = Propagation.REQUIRED) public UserAccount checkLogin(String userName, String pwd) { //* Find the user in the DB Query queryUserAccount = entityManager.createQuery("select u from UserAccount u where (u.username = :userName) and (u.password = :pwd)"); ....... } } loginController.java @Controller @SessionAttributes({"userAccount"}) public class LoginLogOutController { private static final Logger logger = LoggerFactory.getLogger(UserAccount.class); @Resource private UserAccountDAO userDAO; @RequestMapping(value="/loginForm.htm", method = RequestMethod.GET) public String showloginForm(Map model) { logger.debug("Get login form"); UserAccount userAccount = new UserAccount(); model.put("userAccount", userAccount); return "loginform"; } ... Error Stack INFO: 13:52:21,657 ERROR ContextLoader:220 - Context initialization failed org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'loginController': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userAccountDAO': Injection of persistence dependencies failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No unique bean of type [javax.persistence.EntityManagerFactory] is defined: expected single bean but found 0 at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessPropertyValues(CommonAnnotationBeanPostProcessor.java:300) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1074) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:580) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425) at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:276) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:197) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:47) at org.apache.catalina.core.StandardContext.contextListenerStart(StandardContext.java:4664) at com.sun.enterprise.web.WebModule.contextListenerStart(WebModule.java:535) at org.apache.catalina.core.StandardContext.start(StandardContext.java:5266) at com.sun.enterprise.web.WebModule.start(WebModule.java:499) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:928) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:912) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:694) at com.sun.enterprise.web.WebContainer.loadWebModule(WebContainer.java:1947) at com.sun.enterprise.web.WebContainer.loadWebModule(WebContainer.java:1619) at com.sun.enterprise.web.WebApplication.start(WebApplication.java:90) at org.glassfish.internal.data.EngineRef.start(EngineRef.java:126) at org.glassfish.internal.data.ModuleInfo.start(ModuleInfo.java:241) at org.glassfish.internal.data.ApplicationInfo.start(ApplicationInfo.java:236) at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:339) at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:183) at org.glassfish.deployment.admin.DeployCommand.execute(DeployCommand.java:272) at com.sun.enterprise.v3.admin.CommandRunnerImpl$1.execute(CommandRunnerImpl.java:305) at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:320) at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:1176) at com.sun.enterprise.v3.admin.CommandRunnerImpl.access$900(CommandRunnerImpl.java:83) at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1235) at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1224) at com.sun.enterprise.v3.admin.AdminAdapter.doCommand(AdminAdapter.java:365) at com.sun.enterprise.v3.admin.AdminAdapter.service(AdminAdapter.java:204) at com.sun.grizzly.tcp.http11.GrizzlyAdapter.service(GrizzlyAdapter.java:166) at com.sun.enterprise.v3.server.HK2Dispatcher.dispath(HK2Dispatcher.java:100) at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:245) at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:791) at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:693) at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:954) at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:170) at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:135) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:102) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:88) at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:76) at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:53) at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:57) at com.sun.grizzly.ContextTask.run(ContextTask.java:69) at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:330) at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:309) at java.lang.Thread.run(Thread.java:732)

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  • ExecutorService memory leak on exception

    - by TofuBeer
    I am having a hard time tracking this down since the profiler keeps crashing (hotspot error). Before I go too deep into figuring it out I'd like to know if I really have a problem or not :-) I have a few thread pools created via: Executors.newFixedThreadPool(10); The threads connect to different web sites and, on occasion, I get connection refused and wind up throwing an exception. When I later on call Future.get() to get the result it will then catch the ExecutionException that wraps the exception that was thrown when the connection could not be made. The program uses a fairly constant amount of memory up until the point in time that the exceptions get thrown (they tend to happen in batches when a particular site is overloaded). After that point the memory again remains constant but at a higher level. So my question is along the lines of is the memory behaviour (reported by "top" on Unix) expected because the exceptions just triggered something or do I probably have an actual leak that I'll need to track down? Additionally when Future.get() throws an exception is there anything else I need to do besides catch the exception (such as call Future.cancel() on it)?

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  • Implementing Excel 2003 COM Add-in UDF in Asyc Programming model using C#(VS 2005)

    - by Venu
    Hi: I am trying to implement a UDF using Excel COM Add-in(2003) with Visual Studio 2005 in C#. I would like to implement the UDF using async programming. The UDF is a slow operation as its results are fetched from a server. As an illustration(not a real world example),the following UDF works fine without any issue: public double mul(double number1, double number2) { return number1 * number2; } How can I do the same functionality in an async way: For example, I would like the UDF return immediately and later when the results are available from a server, I would like to update the desired cells. // This method returns immediately. public object mul(double number1, double number2) { return "calculating"; } // This method of a worker thread will update the results. public OnResultsAvailable(object result) { // Question: how should I update the cells that triggerred the calcualtions above? } Constraints: I cannot use Excel RTD as I have to work with existing codebase written using Excel C# COM Add-in. Thanks for the help. -Venu

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