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  • Maven + AspectJ - all steps to configure it

    - by Alice
    I have a problem with applying aspects to my maven project. Probably I am missing something, so I've made a list of steps. Could you please check if it is correct? Let say in projectA is an aspect class and in projectB classes, which should be changed by aspects. Create maven project ProjectA with AspectJ class add Aspectj plugin and dependency Add ProjectA as a dependency to projectB pom.xml Add to projectB pom.xml plugin " <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>aspectj-maven-plugin</artifactId> <version>1.4</version> <executions> <execution> <goals> <goal>compile</goal> <goal>test-compile</goal> </goals> </execution> </executions> <configuration> <source>${maven.compiler.source}</source> <target>${maven.compiler.target}</target> <aspectLibraries> <aspectLibrary> <groupId>ProjectA</groupId> <artifactId>ProjectA</artifactId> </aspectLibrary> </aspectLibraries> </configuration> </plugin> Add aspectj dependency After all these steps my problem is, that during compilation I get: [WARNING] advice defined in AspectE has not been applied [Xlint:adviceDidNotMatch] And then when I run my program: Exception in thread "FeatureExcutionThread" java.lang.NoClassDefFoundError: AspectE

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  • ExecutorSerrvice 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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  • Insert or Update using Oracle and PL/SQL

    - by Shane
    I have a PL/SQL function that performs an update/insert on an Oracle database that maintains a target total and returns the difference between the existing value and the new value. Here is the code I have so far: FUNCTION calcTargetTotal(accountId varchar2, newTotal numeric ) RETURN number is oldTotal numeric(20,6); difference numeric(20,6); begin difference := 0; begin select value into oldTotal from target_total WHERE account_id = accountId for update of value; if (oldTotal != newTotal) then update target_total set value = newTotal WHERE account_id = accountId difference := newTotal - oldTotal; end if; exception when NO_DATA_FOUND then begin difference := newTotal; insert into target_total ( account_id, value ) values ( accountId, newTotal ); -- sometimes a race condition occurs and this stmt fails -- in those cases try to update again exception when DUP_VAL_ON_INDEX then begin difference := 0; select value into oldTotal from target_total WHERE account_id = accountId for update of value; if (oldTotal != newTotal) then update target_total set value = newTotal WHERE account_id = accountId difference := newTotal - oldTotal; end if; end; end; end; return difference end calcTargetTotal; This works as expected in unit tests with multiple threads never failing. However when loaded on a live system we have seen this fail with a stack trace looking like this: ORA-01403: no data found ORA-00001: unique constraint () violated ORA-01403: no data found The line numbers (which I have removed since they are meaningless out of context) verify that the first update fails due to no data, the insert fail due to uniqueness, and the 2nd update is failing with no data, which should be impossible. From what I have read on other thread a MERGE statement is also not atomic and could suffer similar problems. Does anyone have any ideas how to prevent this from occurring?

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  • How to improve multi-threaded access to Cache (custom implementation)

    - by Andy
    I have a custom Cache implementation, which allows to cache TCacheable<TKey> descendants using LRU (Least Recently Used) cache replacement algorithm. Every time an element is accessed, it is bubbled up to the top of the LRU queue using the following synchronized function: // a single instance is created to handle all TCacheable<T> elements public class Cache() { private object syncQueue = new object(); private void topQueue(TCacheable<T> el) { lock (syncQueue) if (newest != el) { if (el.elder != null) el.elder.newer = el.newer; if (el.newer != null) el.newer.elder = el.elder; if (oldest == el) oldest = el.newer; if (oldest == null) oldest = el; if (newest != null) newest.newer = el; el.newer = null; el.elder = newest; newest = el; } } } The bottleneck in this function is the lock() operator, which limits cache access to just one thread at a time. Question: Is it possible to get rid of lock(syncQueue) in this function while still preserving the queue integrity?

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  • How do you get an object associated with a Future Actor?

    - by Bruce Ferguson
    I would like to be able to get access to the object that is being returned from spawning a future import scala.actors.Future import scala.actors.Futures._ class Object1(i:Int) { def getAValue(): Int = {i} } object Test { def main( args: Array[String] ) = { var tests = List[Future[Object1]]() for(i <- 0 until 10) { val test = future { val obj1 = new Object1(i) println("Processing " + i + "...") Thread.sleep(1000) println("Processed " + i) obj1 } tests = tests ::: List(test) } val timeout = 1000 * 60 * 5 // wait up to 5 minutes val futureTests = awaitAll(timeout,tests: _*) futureTests.foreach(test => println("result: " + future())) } } The output from one run of this code is: Processing 0... Processing 1... Processing 2... Processing 3... Processed 0 Processing 4... Processed 1 Processing 5... Processed 2 Processing 6... Processed 3 Processing 7... Processed 4 Processing 8... Processed 6 Processing 9... Processed 5 Processed 7 Processed 8 Processed 9 result: <function0> result: <function0> result: <function0> result: <function0> result: <function0> result: <function0> result: <function0> result: <function0> result: <function0> result: <function0> I've tried future().getClass(), and the output is result: class scala.actors.FutureActor What I'm looking to be able to access is the obj1 objects. Thanks Bruce

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  • how do I get a new line, after using float:left?

    - by codeman73
    What I am trying to do is have rows of images, 6 images in each row. Some of these images need to have another image floating on top of them (flush with the lower-right corner). I was able to get that to work from this thread: http://stackoverflow.com/questions/48474/how-do-i-position-one-image-on-top-of-another-in-html However, now I'm unable to get the new row after the 6th image. Neither <BR> or <P> create a new line. They simply push the next image down several pixels, but the image is still in the same line. It seems like the float style is interfering with the <BR> and/or <P>. I tried using different styles for the image that starts a new row, like float:none and display:block, but neither worked. The odd thing is that the new line starts after the 7th image. Here's what I'm using so far: <style type="text/css"> .containerdiv { float: left; position: relative; } .containerdivNewLine { float: none; display: block; position: relative; } .cornerimage { position: absolute; bottom: 0; right: 0; } </style> <div class="containerdiv"> <img border="0" height="188" src="myImg" width="133" /> <img class="cornerimage" height="140" src="imageOnTop" width="105" /> </div> For the 7th image, when I'm trying to start a new row, I'm simply replacing the 'containerdiv' class with 'containerdivNewLine'.

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  • How to fix Java Image Fetcher error ?

    - by Frank
    My code looks like this : private static JFileChooser fc; if (fc==null) { fc=new JFileChooser(Image_Dir); fc.addChoosableFileFilter(new Image_Filter()); // Add a custom file filter and disable the default (Accept All) file filter. fc.setAcceptAllFileFilterUsed(false); fc.setAccessory(new Image_Preview(fc)); // Add the preview pane. } int returnVal=fc.showDialog(JFileChooser_For_Image.this,"Get Image"); // Show it. After I select an image from the panel, I got the following error message : Exception in thread "Image Fetcher 0" java.lang.UnsatisfiedLinkError: Native Library C:\Program Files (x86)\Java\jre6\bin\jpeg.dll already loaded in another classloader at java.lang.ClassLoader.loadLibrary0(Unknown Source) at java.lang.ClassLoader.loadLibrary(Unknown Source) at java.lang.Runtime.loadLibrary0(Unknown Source) at java.lang.System.loadLibrary(Unknown Source) at sun.security.action.LoadLibraryAction.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at sun.awt.image.JPEGImageDecoder.<clinit>(Unknown Source) at sun.awt.image.InputStreamImageSource.getDecoder(Unknown Source) at sun.awt.image.FileImageSource.getDecoder(Unknown Source) at sun.awt.image.InputStreamImageSource.doFetch(Unknown Source) at sun.awt.image.ImageFetcher.fetchloop(Unknown Source) at sun.awt.image.ImageFetcher.run(Unknown Source) When I run it from an executable Jar file, it works fine, but after I wrapped it into an exe file, I got the above error, why ? How to fix it ?

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  • Blackberry (Java) - Can't get KeyListener to work

    - by paullb
    I am trying to get the KeyListener working for Blackberry, but none of the Dialogs pop up indicating that a key has been pressed (see code below, each action has a dialog popup in them). Any ideas on what i might be doing wrong? public class CityInfo extends UiApplication implements KeyListener { static CityInfo application; public static void main(String[] args) { //create a new instance of the application //and start the application on the event thread application.enterEventDispatcher(); } public CityInfo() { //display a new screen application = new CityInfo(); pushScreen(new WorkflowDisplayScreen()); this.addKeyListener(this); } public boolean keyChar(char arg0, int arg1, int arg2) { // TODO Auto-generated method stub Dialog.alert("key pressed : " + arg0); return true; } public boolean keyDown(int keycode, int time) { // TODO Auto-generated method stub Dialog.alert("keyDown : " + keycode); return false; } public boolean keyRepeat(int keycode, int time) { // TODO Auto-generated method stub Dialog.alert("keyRepeat : " + keycode); return false; } public boolean keyStatus(int keycode, int time) { // TODO Auto-generated method stub Dialog.alert("keyStatus : " + keycode); return false; } public boolean keyUp(int keycode, int time) { Dialog.alert("keyUp : " + keycode); // TODO Auto-generated method stub return false; } } I also tried implementing keyChar on the MainScreen class but that did not yield any results either.

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  • Is it possible to have an enum field in a class persisted with OrmLite?

    - by htf
    Hello. I'm trying to persist the following class with OrmLite: public class Field { @DatabaseField(id = true) public String name; @DatabaseField(canBeNull = false) public FieldType type; public Field() { } } The FieldType is a public enum. The field, corresponding to the type is string in SQLite (is doesn't support enums). When I try to use it, I get the following exception: INFO [main] (SingleConnectionDataSource.java:244) - Established shared JDBC Connection: org.sqlite.Conn@5224ee Exception in thread "main" org.springframework.beans.factory.BeanInitializationException: Initialization of DAO failed; nested exception is java.lang.IllegalArgumentException: Unknown field class class enums.FieldType for field FieldType:name=type,class=class orm.Field at org.springframework.dao.support.DaoSupport.afterPropertiesSet(DaoSupport.java:51) at orm.FieldDAO.getInstance(FieldDAO.java:17) at orm.Field.fromString(Field.java:23) at orm.Field.main(Field.java:38) Caused by: java.lang.IllegalArgumentException: Unknown field class class enums.FieldType for field FieldType:name=type,class=class orm.Field at com.j256.ormlite.field.FieldType.<init>(FieldType.java:54) at com.j256.ormlite.field.FieldType.createFieldType(FieldType.java:381) at com.j256.ormlite.table.DatabaseTableConfig.fromClass(DatabaseTableConfig.java:82) at com.j256.ormlite.dao.BaseJdbcDao.initDao(BaseJdbcDao.java:116) at org.springframework.dao.support.DaoSupport.afterPropertiesSet(DaoSupport.java:48) ... 3 more So how do I tell OrmLite, values on the Java side are from an enum?

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  • Using tarantula to test a Rails app

    - by Benjamin Oakes
    I'm using Tarantula to test a Rails app I'm developing. It works pretty well, but I'm getting some strange 404s. After looking into it, Tarantula is following DELETE requests (destroy actions on controllers) throughout my app when it tests. Since Tarantula gets the index action first (and seems to keep a list of unvisited URLs), it eventually tries to follow a link to a resource which it had deleted... and gets a 404. Tarantula is right that the URL doesn't exist anymore (because it deleted the resource itself). However, it's flagging it as an error -- that's hardly the behavior I would expect. I'm basically just using the Rails scaffolding and this problem is happening. How do I prevent Tarantula doing this? (Or, is there a better way of specifying the links?) Updates: Still searching, but I found a relevant thread here: http://github.com/relevance/tarantula/issues#issue/3 Seems to be coming from relying on JS too much, in a way (see also http://thelucid.com/2010/03/15/rails-can-we-please-have-a-delete-action-by-default/)

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  • TransactionRequiredException on OptimisticLockException

    - by João Madureira Pires
    Hi there. I have the following class that generates sequencial Card Numbers. I'm trying to recover from OptimisticLockException, by calling recursively the same method. however, i'm getting TransactionRequiredException. Dows anyone knows how to recover from OptimisticLockException in my case? Thanks a lot in advance @Name("simpleAutoIncrementGenerator") public class SimpleAutoIncrementGenerator extends CardNumberGenerator{ private static final long serialVersionUID = 2869548248468809665L; private int numberOfRetries = 0; @Override public String generateNextNumber(CardInstance cardInstance, EntityManager entityManager) { try{ EntityCard card = (EntityCard)entityManager.find(EntityCard.class, cardInstance.getId()); if(card != null){ String nextNumber = ""; String currentNumber = card.getCurrentCardNumber(); if(currentNumber != null && !currentNumber.isEmpty()){ Long numberToInc = Long.parseLong(currentNumber); numberToInc ++; nextNumber = String.valueOf(numberToInc); card.setCurrentCardNumber(nextNumber); // this is just to cause a OptimisticLock Exception try { Thread.sleep(4000); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } entityManager.persist(card); entityManager.flush(); return nextNumber; } } }catch (OptimisticLockException oLE) { System.out.println("\n\n\n\n OptimisticLockException \n\n\n\n"); if(numberOfRetries < CentralizedConfig.CARD_NUMBER_GENERATOR_MAX_TRIES){ numberOfRetries ++; return generateNextNumber(cardInstance,entityManager); } }catch (TransactionRequiredException trE) { System.out.println("\n\n\n\n TransactionRequiredException \n\n\n\n"); if(numberOfRetries < CentralizedConfig.CARD_NUMBER_GENERATOR_MAX_TRIES){ numberOfRetries ++; return generateNextNumber(cardInstance,entityManager); } }catch (StaleObjectStateException e) { System.out.println("\n\n\n\n StaleObjectStateException \n\n\n\n"); if(numberOfRetries < CentralizedConfig.CARD_NUMBER_GENERATOR_MAX_TRIES){ numberOfRetries ++; return generateNextNumber(cardInstance,entityManager); } } return null; } }

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  • C#: socket closing if user user exists

    - by corvallo
    Hi to everyone I'm trying to create a server/client application for a school project. This is the scenario: a server on a given port, multiple user connected, each user has it's own username. Now I want to check if a user that try to connect to the user use a valid username, for example if a user with username A it's already connected a new user that want to connect cannot use the username A. If this happen the server answer to the new client with an error code. This is the code for this part private void Receive() { while (true) { byte[] buffer = new byte[64]; socket.Receive(buffer); string received = Encoding.Default.GetString(buffer); if (received.IndexOf("!error") != -1) { string[] mySplit = received.Split(':'); string errorCode = mySplit[1].Trim((char)0); if (errorCode == "user exists") { richTextBox1.AppendText("Your connection was refused by server, because there's already another user connected with the username you choose"); socket.Disconnect(true); connectBtn.Enabled = true; } } } } But when I try to do this the program crash and visual studio said that there's an invalid cross-thread operation on richTextBox1. Any ideas. Thank you in advance.

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  • Using sigprocmask to implement locks

    - by EpsilonVector
    I'm implementing user threads in Linux kernel 2.4, and I'm using ualarm to invoke context switches between the threads. We have a requirement that our thread library's functions should be uninterruptable, so I looked into blocking signals and learned that using sigprocmask is the standard way to do this. However, it looks like I need to do quite a lot to implement this: sigset_t new_set, old_set; sigemptyset(&new_set); sigaddset(&new_set, SIGALRM); sigprocmask(SIG_BLOCK, &new_set, &old_set); This blocks SIGALARM but it does this with 3 function invocations! A lot can happen in the time it takes for these functions to run, including the signal being sent. The best idea I had to mitigate this was temporarily disabling ualarm, like this: sigset_t new_set, old_set; time=ualarm(0,0); sigemptyset(&new_set); sigaddset(&new_set, SIGALRM); sigprocmask(SIG_BLOCK, &new_set, &old_set); ualarm(time, 0); Which is fine except that this feels verbose. Isn't there a better way to do this?

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  • Java: design for using many executors services and only few threads

    - by Guillaume
    I need to run in parallel multiple threads to perform some tests. My 'test engine' will have n tests to perform, each one doing k sub-tests. Each test result is stored for a later usage. So I have n*k processes that can be ran concurrently. I'm trying to figure how to use the java concurrent tools efficiently. Right now I have an executor service at test level and n executor service at sub test level. I create my list of Callables for the test level. Each test callable will then create another list of callables for the subtest level. When invoked a test callable will subsequently invoke all subtest callables test 1 subtest a1 subtest ...1 subtest k1 test n subtest a2 subtest ...2 subtest k2 call sequence: test manager create test 1 callable test1 callable create subtest a1 to k1 testn callable create subtest an to kn test manager invoke all test callables test1 callable invoke all subtest a1 to k1 testn callable invoke all subtest an to kn This is working fine, but I have a lot of new treads that are created. I can not share executor service since I need to call 'shutdown' on the executors. My idea to fix this problem is to provide the same fixed size thread pool to each executor service. Do you think it is a good design ? Do I miss something more appropriate/simple for doing this ?

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  • Why won't WPF databindings show text when ToString() has a collaborating object?

    - by Jay
    In a simple form, I bind to a number of different objects -- some go in listboxes; some in textblocks. A couple of these objects have collaborating objects upon which the ToString() method calls when doing its work -- typically a formatter of some kind. When I step through the code I see that when the databinding is being set up, ToString() is called the collaborating object is not null and returns the expected result when inspected in the debugger, the objects return the expected result from ToString() BUT the text does not show up in the form. The only common thread I see is that these use a collaborating object, whereas the other bindings that show up as expected simply work from properties and methods of the containing object. If this is confusing, here is the gist in code: public class ThisThingWorks { private SomeObject some_object; public ThisThingWorks(SomeObject s) { some_object = s; } public override string ToString() { return some_object.name; } } public class ThisDoesntWork { private Formatter formatter; private SomeObject some_object; public ThisDoesntWork(SomeObject o, Formatter f) { formatter = f; some_object = o; } public override string ToString() { return formatter.Format(some_object.name); } } Again, let me reiterate -- the ToString() method works in every other context -- but when I bind to the object in WPF and expect it to display the result of ToString(), I get nothing. Update: The issue seems to be what I see as a buggy behaviour in the TextBlock binding. If I bind the Text property to a property of the DataContext that is declared as an interface type, ToString() is never called. If I change the property declaration to an implementation of the interface, it works as expected. Other controls, like Label work fine when binding the Content property to a DataContext property declared as either the implementation or the interface. Because this is so far removed from the title and content of this question, I've created a new question here: http://stackoverflow.com/questions/2917878/why-doesnt-textblock-databinding-call-tostring-on-a-property-whose-compile-tim

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  • unhandled exception Handler in .Net 3.5 SP1

    - by Ruony
    Hi. I'm converting my own web browser use WPF from Windows XP to Windows 7. when I test on Windows XP, It has no error and exceptions. But I convert and test on Windows 7 with Multi-touch Library, My Browser occurred unhandled exception. Source: PresentationCore Message: An unspecified error occurred on the render thread. StackTrace: at System.Windows.Media.MediaContext.**NotifyPartitionIsZombie**(Int32 failureCode) at System.Windows.Media.MediaContext.NotifyChannelMessage() at System.Windows.Interop.HwndTarget.HandleMessage(Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Interop.HwndSource.HwndTargetFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o) at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter) at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler) InnerException: null I want to know where the bug occurred. That Trace Message are garbage information for me. I already googling to know that message, but i never found any information. How do I get exactly function where the bug occurred? please tell me something.

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  • java , eclipse jar problem

    - by Raxvan
    Hello , i'm kind of new to java. I use eclipse and i imported some jar files with some classes by going to properties - Add External Jars; The problem is that when i try to use a class from the jar i get the following exception: Exception in thread "main" java.lang.NoClassDefFoundError: nextapp/echo2/app/event/ActionListener at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(Unknown Source) at java.security.SecureClassLoader.defineClass(Unknown Source) at java.net.URLClassLoader.defineClass(Unknown Source) at java.net.URLClassLoader.access$000(Unknown Source) at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClassInternal(Unknown Source) at Program.main(Program.java:12) Caused by: java.lang.ClassNotFoundException: nextapp.echo2.app.event.ActionListener at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClassInternal(Unknown Source) ... 13 more The class is supposed to create a window, i guess that the jar has to import somehow other stuff or something like that, How can i fix this? PS. Sorry for the bad code , i don't know tags here. thansk, Raxvan

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  • Java abstract visitor - guarantueed to succeed? If so, why?

    - by disown
    I was dealing with hibernate, trying to figure out the run-time class behind proxied instances by using the visitor pattern. I then came up with an AbstractVisitable approach, but I wonder if it will always produce correct results. Consider the following code: interface Visitable { public void accept(Visitor v); } interface Visitor { public void visit(Visitable visitorHost); } abstract class AbstractVisitable implements Visitable { @Override public void accept(Visitor v) { v.visit(this); } } class ConcreteVisitable extends AbstractVisitable { public static void main(String[] args) { final Visitable visitable = new ConcreteVisitable(); final Visitable proxyVisitable = (Visitable) Proxy.newProxyInstance( Thread.currentThread().getContextClassLoader(), new Class<?>[] { Visitable.class }, new InvocationHandler() { @Override public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { return method.invoke(visitable, args); } }); proxyVisitable.accept(new Visitor() { @Override public void visit(Visitable visitorHost) { System.out.println(visitorHost.getClass()); } }); } } This makes a ConcreteVisitable which inherits the accept method from AbstractVisitable. In c++, I would consider this risky, since this in AbstractVisitable could be referencing to AbstractVisitable::this, and not ConcreteVisitable::this. I was worried that the code under certain circumstances would print class AbstractVisible. Yet the code above outputs class ConcreteVisitable, even though I hid the real type behind a dynamic proxy (the most difficult case I could come up with). Is the abstract visitor approach above guaranteed to work, or are there some pitfalls with this approach? What guarantees are given in Java with respect to the this pointer?

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  • Groovy & Grails Concurrency ( quartz, executor )

    - by Pietro
    What I'm trying to do is to run multiple threads at some starting time. Those threads must stay alive for 90minutes after start. During the 90minutes they execute something after a random sleep time (ex: 5minutes to 15minutes). Here is a pseudo code on how I would implement it. The problem is that doing it in this way the threads run in an unexpected way. How can I implement correctly something like this? Class MyJob { static triggers = { cron name: 'first', cronExpression: "0 30 21 * * FRI" cron name: 'second', cronExpression: "0 30 19 * * FRI" cron name: 'third', cronExpression: "0 30 17 * * FRI" def myService def execute() { switch( between trigger name ) case 'first': model = Model.findByAttribute(...) ... myService.run( model, start_time ) break; ... } } class MyService { def run( model, start_time ) { def end_time = end_time.plusMinutes(90) model.fields.each( field -> Thread.start { executeSomeTasks( field, start_time, end_time ) } ) } def executeSomeTasks( field, start_time, end_time ) { while( start_time < end_time ) { ...do something ... sleep( Random.nextInt( 1000 ) ); } } }

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  • GUI blocked while running silent app VC++

    - by deb
    Hi, I have built a GUI interface in C++ (Windows XP, visual c++ 2008). There you can configure some parameters and when I click on the OK button, a silent application is launched (and uses the values setted). When I do this, the GUI frozes and even dissappears if you switch to other windows(it's still there, but you can only see a white space), when the other application's finished the GUI works again. This is the correct behaviour, I don't want the user to be able to edit the fields... but it's a bit ugly when you can't see the GUI. Does anybody know an easy way of being able to switch to other windows and being able to see the the GUI when you switch back? Thanks in advance Edited: Hi, I tried doing this, but the problem is that to run the apps in background I had a function that uses CreateProcess. So both ways the GUI gets frozen: if I create a Thread that creates the process and if I creathe the process directly. Then I wait for the process to finish: if (!CreateProcess( NULL, Args, NULL, NULL, FALSE, CREATE_NEW_CONSOLE, NULL, NULL, &StartupInfo, &ProcessInfo)) { return GetLastError(); } WaitForSingleObject(ProcessInfo.hProcess, INFINITE); if(!GetExitCodeProcess(ProcessInfo.hProcess, &rc)) rc = 0; Any idea?

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  • How to parse time stamps with Unicode characters in Java or Perl?

    - by ram
    I'm trying to make my code as generic as possible. I'm trying to parse install time of a product installation. I will have two files in the product, one that has time stamp I need to parse and other file tells the language of the installation. This is how I'm parsing the timestamp public class ts { public static void main (String[] args){ String installTime = "2009/11/26 \u4e0b\u5348 04:40:54"; //This timestamp I got from the first file. Those unicode charecters are some Chinese charecters...AM/PM I guess //Locale = new Locale();//don't set the language yet SimpleDateFormat df = (SimpleDateFormat)DateFormat.getDateTimeInstance(DateFormat.DEFAULT,DateFormat.DEFAULT); Date instTime = null; try { instTime = df.parse(installTime); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println(instTime.toString()); } } The output I get is Parsing Failed java.text.ParseException: Unparseable date: "2009/11/26 \u4e0b\u5348 04:40:54" at java.text.DateFormat.parse(Unknown Source) at ts.main(ts.java:39) Exception in thread "main" java.lang.NullPointerException at ts.main(ts.java:45) It throws exception and at the end when I print it, it shows some proper date... wrong though. I would really appreciate if you could clarify me on these doubts How to parse timestamps that have unicode characters if this is not the proper way? If parsing is failed, how could instTime able to hold some date, wrong though? I know its some chinese,Korean time stamps so I set the locale to zh and ko as follows.. even then same error comes again Locale = new Locale("ko"); Locale = new Locale("ja"); Locale = new Locale("zh"); How can I do the same thing in Perl? I can't use Date::Manip package; Is there any other way?

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  • Would an immutable keyword in Java be a good idea?

    - by berry120
    Generally speaking, the more I use immutable objects in Java the more I'm thinking they're a great idea. They've got lots of advantages from automatically being thread-safe to not needing to worry about cloning or copy constructors. This has got me thinking, would an "immutable" keyword go amiss? Obviously there's the disadvantages with adding another reserved word to the language, and I doubt it will actually happen primarily for the above reason - but ignoring that I can't really see many disadvantages. At present great care has to be taken to make sure objects are immutable, and even then a dodgy javadoc comment claiming a component object is immutable when it's in fact not can wreck the whole thing. There's also the argument that even basic objects like string aren't truly immutable because they're easily vunerable to reflection attacks. If we had an immutable keyword the compiler could surely recursively check and give an iron clad guarantee that all instances of a class were immutable, something that can't presently be done. Especially with concurrency becoming more and more used, I personally think it'd be good to add a keyword to this effect. But are there any disadvantages or implementation details I'm missing that makes this a bad idea?

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  • Loading JNI lib on Mac OS X?

    - by Clinton
    Background So I am attempting to load a jnilib (specifically JOGL) into Java on Mac OS X at runtime. I have been following along the relevant Stack Overflow questions: Maven and the JOGL Library Loading DLL in Java - Eclipse - JNI How to make a jar file that include all jar files The end goal for me is to package platform specific JOGL files into a JAR and unzip them into a temp directory and load them at start-up. I worked my problem back to simply attempting to load JOGL using hard-coded paths: File f = new File("/var/folders/+n/+nfb8NHsHiSpEh6AHMCyvE+++TI/-Tmp-/libjogl.jnilib"); System.load(f.toString()); f = new File ("/var/folders/+n/+nfb8NHsHiSpEh6AHMCyvE+++TI/-Tmp-/libjogl_awt.jnilib"); System.load(f.toString()); I get the following exception when attempting to use the JOGL API: Exception in thread "main" java.lang.UnsatisfiedLinkError: no jogl in java.library.path But when I specify java.library.path by adding the following JVM option: -Djava.library.path="/var/folders/+n/+nfb8NHsHiSpEh6AHMCyvE+++TI/-Tmp-/" Everything works fine. Question Is it possible use System.load (or some other variant) on Mac OS X as a replacement for -Djava.library.path that is invoked at runtime?

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  • Should I pass a SqlDataReader by reference or not when passing it out to multiple threads.

    - by deroby
    Hi all, being new to c# I've run into this 'conundrum' when passing around a SqlDataReader between different threads. Without going into too much detail, the idea is to have a main thread fetching data from the database (a large recordset) and then have a helper-task run through this record by record and doing some stuff based upon the contents of this. There is no feedback to the recordset, it simply wades through until no records are left. This works fine, but given the nature of the job at hand it should be possible to have this job spread over different threads (CPUs) to maximize throughput (the order of execution is of no significance). The question then becomes, when I pass this recordset in a SqlDataReader, do I have to use ref or not ? It kind of boils down to the question : if I pass the object around without specifying ref, won't it create new copies in memory and have records processed n times ? Or, don't I risk having the record-position being moved forward while not all fields have been fully read yet ? The latter seems more like a 'data racing' issue and probably is covered by the lock()ing mechanism (or not?). My initial take on the problem was that it doesn't really hurt passing the variable using ref, yet as a colleague put it : "you only need ref when you're doing something wrong" =) Additionally using ref restricts me from applying a Using() construction too which isn't very nice either. I thus create a "basic" project that tackles the same approach but without the ref notation. Tests so far show that it works flawlessly on a Core2Duo (2cpu) using any number of threads, yet I'm still a bit wary... What do you experts think about this ? Use ref or not ? You can find the test-project here as it seems I can't upload it to this question directly ?!? ps: it's just a test-project and I'm new to c#, so please be gentle on me when breaking down the code =P

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  • Large ListView containing images in Android

    - by Marco W.
    For various Android applications, I need large ListViews, i.e. such views with 100-300 entries. All entries must be loaded in bulk when the application is started, as some sorting and processing is necessary and the application cannot know which items to display first, otherwise. So far, I've been loading the images for all items in bulk as well, which are then saved in an ArrayList<CustomType> together with the rest of the data for each entry. But of course, this is not a good practice, as you're very likely to have an OutOfMemoryException then: The references to all images in the ArrayList prevent the garbage collector from working. So the best solution is, obviously, to load only the text data in bulk whereas the images are then loaded as needed, right? The Google Play application does this, for example: You can see that images are loaded as you scroll to them, i.e. they are probably loaded in the adapter's getView() method. But with Google Play, this is a different problem, anyway, as the images must be loaded from the Internet, which is not the case for me. My problem is not that loading the images takes too long, but storing them requires too much memory. So what should I do with the images? Load in getView(), when they are really needed? Would make scrolling sluggish. So calling an AsyncTask then? Or just a normal Thread? Parametrize it? I could save the images that are already loaded into a HashMap<String,Bitmap>, so that they don't need to be loaded again in getView(). But if this is done, you have the memory problem again: The HashMap stores references to all images, so in the end, you could have the OutOfMemoryException again. I know that there are already lots of questions here that discuss "Lazy loading" of images. But they mainly cover the problem of slow loading, not too much memory consumption.

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