Problem with threads hanging

We have a problem where our application stops responding after a few days of usage. Things will for fine for a day or two, and then pretty quickly threads will start getting hung up, usually in places where they are allocating memory
We are running WebLogic 8.1 SP2 on Sun JDK 1.4.2_04 on Solaris 8 using the alternate threading model and the -server hotspot vm. We are running pretty much the same code that we had no problems with under WebLogic 6.1 SP4 and Sun JDK 1.3.1.
A thread dump usually shows that some or all of our execute threads are in the state "waiting for monitor entry" even though they are not currently waiting on any java locks. Here is a sample thread from the thread dump (we have ~120 threads so I don't want to post the full dump).
=============================================================================================
"ExecuteThread: '8' for queue: 'itgCrmWarExecutionQueue'" daemon prio=5 tid=0x005941d0 nid=0x2c waiting for monitor entry [c807f000..c807fc28]
at java.lang.String.substring(String.java:1446)
at java.lang.String.substring(String.java:1411)
at weblogic.servlet.internal.ServletRequestImpl.getRelativeUri(ServletRequestImpl.java:1872)
at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:3492)
at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:2585)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:197)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:170)
=============================================================================================
String.java line 1446 for this jdk allocates a new String object, and all the other threads in this state also are creating new objects or arrays, etc.
We've done a pstack on this process when it's in this state, and the threads that are in the "waiting for monitor entry" that look like they're allocating memory are all waiting on the same lwp_mutex_lock with some allocation method that's calling into the native TwoGenerationCollectorPolicy.mem_allocate_work (see pstack output below for the same thread as in the thread dump above)
=============================================================================================
----------------- lwp# 44 / thread# 44 --------------------
ff31f364 lwp_mutex_lock (e3d70)
fee92384 __1cNObjectMonitorGenter26MpnGThread__v_ (5000, 525c, 5000, 50dc, 4800, 4af0) + 2d8
fee324d4 __1cSObjectSynchronizerKfast_enter6FnGHandle_pnJBasicLock_pnGThread__v_ (c807f65c, c807f7d4, 5941d0, 0, 35d654, fee328ec) + 68
fee32954 __1cQinstanceRefKlassZacquire_pending_list_lock6FpnJBasicLock__v_ (c807f7d4, ff170000, d4680000, 4491d4, fee1bc2c,
0) + 78
fee3167c __1cPVM_GC_OperationNdoit_prologue6M_i_ (c807f7bc, 4400, ff170000, 2d2b8, 4a6268, c807fa18) + 38
fee2e0b0 __1cIVMThreadHexecute6FpnMVM_Operation__v_ (c807f7bc, 963a8, 0, 0, 1, 0) + 90
fed2c2a4 __1cbCTwoGenerationCollectorPolicyRmem_allocate_work6MIii_pnIHeapWord__ (962c0, ff1c29ec, ff1c297c, ff131a26, 4800, 4998) + 160
fed22940 __1cNinstanceKlassRallocate_instance6MpnGThread__pnPinstanceOopDesc__ (ee009020, 5941d0, 15ca581, 3647f0, 4a6268, c807f8c8) + 180
fed34928 __1cLOptoRuntimeFnew_C6FpnMklassOopDesc_pnKJavaThread__v_ (ee009018, 5941d0, 0, 0, 0, 0) + 28
fa435a58 ???????? (ee009018, e86de, 15ca4de, 50dc, 5941d0, c807f9c8)
fb36f9a4 ???????? (0, d412ccd8, ee046c28, ff170000, 0, 0)
fad8b278 ???????? (ee046c28, d6000c90, ee046530, 8, db8e8450, c807f9e8)
fad62abc ???????? (d412ccd8, ee046530, d6000c90, ee3bfa38, 8, c807fa18)
fa4b3c38 ???????? (c807fb9c, 0, f2134700, fa415e50, 8, c807faa8)
fa40010c ???????? (c807fc28, c807fe90, a, ee9e1e20, 4, c807fb40)
fed5d48c __1cJJavaCallsLcall_helper6FpnJJavaValue_pnMmethodHandle_pnRJavaCallArguments_pnGThread__v_ (c807fe88, c807fcf0, c807fda8, 5941d0, 5941d0, c807fd00) + 27c
fee4b784 __1cJJavaCallsMcall_virtual6FpnJJavaValue_nLKlassHandle_nMsymbolHandle_4pnRJavaCallArguments_pnGThread__v_ (ff170000, 594778, c807fd9c, c807fd98, c807fda8, 5941d0) + 164
fee5e8dc __1cJJavaCallsMcall_virtual6FpnJJavaValue_nGHandle_nLKlassHandle_nMsymbolHandle_5pnGThread__v_ (c807fe88, c807fe84, c807fe7c, c807fe74, c807fe6c, 5941d0) + 6c
fee6fc74 __1cMthread_entry6FpnKJavaThread_pnGThread__v_ (5941d0, 5941d0, 838588, 594778, 306d10, fee69254) + 128
fee6927c __1cKJavaThreadDrun6M_v_ (5941d0, 2c, 40, 0, 40, 0) + 284
fee6575c _start   (5941d0, fa1a1600, 0, 0, 0, 0) + 134
ff3758c0 lwpstart (0, 0, 0, 0, 0, 0)
=============================================================================================
Also when it's having this problem, the "VM Thread" is always using a lot of processor time. We did a couple of pstacks today while it was having this problem, and this thread was stuck in the ONMethodSweeper.sweep for over 15 minutes when we finally killed the server.
From the thread dump:
"VM Thread" prio=5 tid=0x000e2d20 nid=0x2 runnable
From the first pstack:
=============================================================================================
----------------- lwp# 2 / thread# 2 --------------------
fed40c04 __1cXvirtual_call_RelocationIparse_ic6FrpnICodeBlob_rpC5rppnHoopDesc_pi_nNRelocIterator__ (42a2f4, fa5fa46d, ffffffff, fc4ffcb8, 42a2f4, 42a324) + 124
fed46318 __1cKCompiledIC2t5B6MpnKRelocation__v_ (42a2f0, fc4ffd24, fc4ffd4c, e802, 0, 6) + 38
fed90c38 __1cHnmethodVcleanup_inline_caches6M_v_ (fa5f7f88, fa608940, 1, 0, fa400000, 6) + 1ac
fede18b4 __1cONMethodSweeperFsweep6F_v_ (2cf38, 0, ffffffff, ff1cf1fc, ff1c66e8, fede1d44) + 1b0
fede1e6c __1cUSafepointSynchronizeFbegin6F_v_ (2cf38, ff1ba138, 5000, 50dc, 5000, 525c) + 248
feef1fd4 __1cIVMThreadEloop6M_v_ (4400, 4000, 4324, 4000, 42b0, 3800) + 3d4
feef1ae4 __1cIVMThreadDrun6M_v_ (e2d20, 2, 40, 0, 40, 0) + 8c
fee6575c _start   (e2d20, ff270200, 0, 0, 0, 0) + 134
ff3758c0 lwpstart (0, 0, 0, 0, 0, 0)
=============================================================================================
Second pstack
=============================================================================================
----------------- lwp# 2 / thread# 2 --------------------
fed41180 __1cXvirtual_call_RelocationIparse_ic6FrpnICodeBlob_rpC5rppnHoopDesc_pi_nNRelocIterator__ (0, ff1b9664, ffffffff, fc4ffcb8, a6f2cc, fc4ffbd0) + 6a0
fed46318 __1cKCompiledIC2t5B6MpnKRelocation__v_ (a6f2c8, fc4ffd24, fc4ffd4c, e802, 0, 6) + 38
fed90c38 __1cHnmethodVcleanup_inline_caches6M_v_ (faded4c8, fadf2c80, 1, 0, fa400000, 6) + 1ac
fede18b4 __1cONMethodSweeperFsweep6F_v_ (2cf38, 0, ffffffff, ff1cf1fc, ff1c66e8, fede1d44) + 1b0
fede1e6c __1cUSafepointSynchronizeFbegin6F_v_ (2cf38, ff1ba138, 5000, 50dc, 5000, 525c) + 248
feef1fd4 __1cIVMThreadEloop6M_v_ (4400, 4000, 4324, 4000, 42b0, 3800) + 3d4
feef1ae4 __1cIVMThreadDrun6M_v_ (e2d20, 2, 40, 0, 40, 0) + 8c
fee6575c _start   (e2d20, ff270200, 0, 0, 0, 0) + 134
ff3758c0 lwpstart (0, 0, 0, 0, 0, 0)
=============================================================================================
Has anyone ever seen anything like this? I'm trying to figure out if this is caused by something we're doing, or something relating to our environment and jvm options. Any ideas?

Thanks for the reply - I'm testing our app with the +UseConcMarkSweepGC now in our test environment to make sure it doesn't cause any problems there. Unfortunately the only place we've had this problem is on the production server, so it's extra difficult debugging this.
We're using the following memory options:
-ms512m -mx512m -XX:NewSize=128m -XX:PermSize=192m -XX:MaxNewSize=128m -XX:MaxPermSize=192m -XX:SurvivorRatio=8and the following debugging options, as we've also been seeing OutOfMemoryErrors ( see http://forum.java.sun.com/thread.jsp?forum=37&thread=522354&tstart=45&trange=15 )
-verbosegc -XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGCBTW, which c++filt version and options are you using? Our Solaris boxes only seem to have the GNU version installed. I was trying to run that on some of the other stack traces and wasn't getting anywhere, and didn't know if because it was GNU version wouldn't work on something compiled with the Sun compiler.
Thanks!
--Andy

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catch(Exception e){
// System.out.println("ERROR: Client Connection reset failure");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Client Connection reset failure", JOptionPane.ERROR_MESSAGE);
}// end while
} // end method run
* method run - Generates io stream for communicating with the server and
* starts the client gui. Run also parses the input commands from the server.
public void run(){
boolean alive = true;
try{
// begin to life the gui
// aGuiClient = new ClientGui(hostName.getHostName(), hostPort, loginName, this);
// aGuiClient.show();
in = new BufferedReader(new InputStreamReader(hostSocket.getInputStream()));
out = new PrintWriter(new OutputStreamWriter(hostSocket.getOutputStream()));
while (alive && hostSocket.isConnected()){
String line;
while(((line = in.readLine())!= null)){
System.out.println(line);
broadCast(line);
} // end while
} // end while
catch(Exception e){
//     System.out.println("ERRORa Connection to host reset");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Connection to nPort reset", JOptionPane.ERROR_MESSAGE);
try{
hostSocket.close();
     }catch(Exception a){
     JOptionPane.showMessageDialog(null, (a.toString()),"ERROR: Exception", JOptionPane.ERROR_MESSAGE);
alive = false;
System.exit(1);
} // end method run

Problem with threads and camera.

Hi everybody!
I've a problem with taking snapshot.
I would like to display a loading screen after it take snapshot ( sometimes i
have to wait few seconds after i took snapshot. Propably photo is being taken in time where i have to wait).
I was trying to use threads but i didn't succeed.
I made this code:
display.setCurrent(perform);
        new Thread(new Runnable(){
            public void run() {
                while((!performing.isShown()) && (backgroundCamera.isShown())){
                    Thread.yield();
                notifyAll();
        }).start();
        new Thread(new Runnable(){
            public void run() {
                try {
                    this.wait();
                } catch(Exception e) {
                    exceptionHandler(e);
                photo = camera.snapshot();
                display.setCurrent(displayPhoto);
        }).start();This code is sometimes showing performing screen but sometimes no.
I don't know why. In my opinion performing.isShown() method isn't working correctly.
Does anyone have some idea how to use threads here?

Hi,
I've finally managed to work this fine.
The code:
       Object o = new Object();
       display.setCurrent(perform);
        new Thread(new Runnable(){
            public void run() {
                while(!performing.isShown()){
                    Thread.yield();
               synchronized(o) {
                  o.notify();
        }).start();
        new Thread(new Runnable(){
            public void run() {
                try {
                    synchronized(o) {
                       o.wait(1);
                } catch(Exception e) {
                    exceptionHandler(e);
                photo = camera.snapshot();
                display.setCurrent(displayPhoto);
        }).start();

Problem with threads and ProgressMonitor

Dear Friends:
I have a little problem with a thread and a ProgressMonitor. I have a long time process that runs in a thread (the thread is in an separate class). The thread has a ProgressMonitor that works fine and shows the tasks progress.
But I need deactivate the main class(the main class is the user interface) until the thread ends.
I use something like this:
LongTask myTask=new LongTask();
myTask.start();
myTask.join();
Now, the main class waits for the task to end, but the progress monitor don`t works fine: it shows only the dialog but not the progress bar.
What's wrong?

Is the dialog a modal dialog? This can block other UI updates.
In general, you should make sure that it isn't modal, and that your workThread has a fairly low priority so that the UI can do its updating

Problems with Threads after upgrade to 817 on Tru64.

Hewwo.
I am wondering if you can help me with the following error and, perhaps, tell me how to relink the executables for Oracle. I cannot figure out where -laio_raw has been set. I've poured through the env*.mk files, and looked through the stuff in ~/install/utl directory, but I cannot find out how to respond to the error message below and remake the Oracle apps correctly. Surprisingly, svrmgrl works fine.
dstyo404:orafs2 50> sqlplus system/manager
Internal AIO consistency error: Cannot use libaio_raw with threads.
Either relink without -pthread or link -laio, not -laio_raw.
Aborting...
exception system: exiting due to multiple internal errors:
exception dispatch or unwind stuck in infinite loop
exception dispatch or unwind stuck in infinite loop
Thank you for your time.

To answer my own question, there is a file in $ORACLE_HOME/lib/ called "sysliblist". In order to relink the executables without aio_raw, it must be deleted from this list; and, in it's place, put "-laio". This will solve the above errors with sqlplus, exp, etc.
Hmph.
null

J2ME problem with threads

Hi all,
I would like to ask you for a help. I need to write a small program at my university. I started to write a midlet which function would be to countdown time for sports activities. I woul like to start a new thread - the one that counts down - and at the same time make the main thread sleep. After the "countdown" thread finishes, the main thread wakes up and waits for user input. The problem is that when the "countdown" thread finishes his work, I've got Uncaught exception java/lang/NullPointerException. error and the midlet halts.
Below you can find the code
import java.lang.*;
import java.util.*;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
public class intervals extends MIDlet implements CommandListener
public Display ekran;
private SweepCanvas sweeper;
private Form rundy;
private TextField round0, round1, round2, round3, round4, round5, round6, round7, round8;
private long czas,x;
private Command exitCommand;
private Command addRound;
private Command delRound;
private Command start;
private TextField repeat;
private Form odliczanie;
private Alert ostrz;
Licznik thread;
String test;
StringItem test1;
int parz,i,j,k;
static int l;
int ilrund;
int ilpowt;
Item sec;
long sec1;
public intervals()
    rundy = new Form("Interwały sportowe");
    exitCommand = new Command("Wyjście", Command.EXIT, 2);
    addRound = new Command("Dodaj","Dodaj rundę", Command.ITEM,1);
    delRound = new Command("Usuń","Usuń ostatnią rundę", Command.ITEM,1);
    start = new Command("Start", Command.ITEM,1);
    odliczanie = new Form("Odliczanie");
    TextField dodaj(TextField kolej)
        kolej=new TextField("Podaj czas (s) rundy "+parz,null, 4, TextField.NUMERIC);//stworzenie nowej instancji do wybierania czasu trwania rundy
        if(rundy.size()==0)
            rundy.insert(rundy.size(),kolej);
            else
                rundy.insert(rundy.size()-1, kolej);
        return kolej;
    void odliczanie(TextField round)
        monitor m=new monitor();
        k=Integer.parseInt(round.getString());
        ekran.setCurrent(odliczanie);
        thread=new Licznik(k,odliczanie);
        thread.start();
        ekran.setCurrent(rundy);
public void startApp()// throws MIDletStateChangeException
    rundy.deleteAll();
    repeat = new TextField("Podaj ilość powtórzeń",null,1,TextField.NUMERIC);
    rundy.addCommand(addRound);
    rundy.addCommand(exitCommand);
    rundy.setCommandListener(this);
    Canvas obrazek = new MyCanvas();
    ekran = Display.getDisplay(this);
    ekran.setCurrent(obrazek);
    czas=System.currentTimeMillis();
    while (System.currentTimeMillis()<czas+1000)
        continue;
    ekran.setCurrent(rundy);
public void pauseApp()
public void destroyApp(boolean unconditional)
    notifyDestroyed();
public void commandAction(Command c, Displayable s)
    if (c == exitCommand)
        destroyApp(false);
        notifyDestroyed();
    else if(c==addRound)
        if(rundy.size()==0)//Sprawdzenie ilości elementów w celu poprawnego wyświetlania liczby rund w formie
            parz=1;
            else
            parz=rundy.size();
        switch(parz)
            case 1:
                round0=dodaj(round0);break;
            case 2:
                round1=dodaj(round1);break;
            case 3:
               round2= dodaj(round2);break;
            case 4:
                round3=dodaj(round3);break;
            case 5:
                round4=dodaj(round4);break;
            default:
                ostrz=new Alert("Uwaga","Maksymalna liczba rund wynosi 9", null, AlertType.INFO);
                ostrz.setTimeout(3000);
                ekran.setCurrent(ostrz);
        if(rundy.size()==1)
            rundy.append(repeat);
            rundy.addCommand(start);
        rundy.addCommand(delRound);
    else if(c==delRound)
        if(rundy.size()!=0)
            rundy.delete(rundy.size()-2);
            if (rundy.size()==1)
                rundy.deleteAll();
            if(rundy.size()==0)
                rundy.removeCommand(delRound);
                rundy.removeCommand(start);
    else if(c==start)
        ilrund=rundy.size()-1;
        if(this.repeat.size()>0)
            ilpowt=Integer.parseInt(this.repeat.getString());
        ekran = Display.getDisplay(this);
        for (i=1; i<=ilpowt;i++)
            odliczanie= new Form("Odliczanie");
             for (j=0;j<ilrund;j++)
                switch(j)
                     case 0:
                         odliczanie(round0);
                         break;
                     case 1:
                         odliczanie(round1);
                         break;
                     case 2:
                         odliczanie(round2);
                         break;
                     case 3:
                         odliczanie(round3);
                         break;
                     case 4:
                         odliczanie(round4);
                         break;
                     case 5:
                         odliczanie(round5);
                         break;
                     case 6:
                         odliczanie(round6);
                         break;
                     case 7:
                         odliczanie(round7);
                         break;
                     case 8:
                         odliczanie(round8);
                         break;
class Licznik extends Thread
    int czas1,k;
    Form forma;
    monitor m;
    public Licznik(int k,Form formap)
        czas1=k;
        forma=formap;
    public synchronized void run()
        while(czas1>0)
            forma.deleteAll();
            forma.append("Czas pozostały (s): "+czas1);
            try{Thread.sleep(1000);} catch(InterruptedException e){e.printStackTrace();}
            czas1--;
        if(czas1<=0)
            m.put();
    }and monitor class
public class monitor
boolean busy=false;
synchronized void get()
    if(!busy)
        try
            wait();
        }catch(InterruptedException e){e.printStackTrace();}
    notify();
synchronized void put()
    if(busy)
        try
        wait();
        }catch(InterruptedException e){e.printStackTrace();}
    busy=true;
    notify();
}Can anybody help me with this?

Groovemaker,
Your Licznik class has a member m of type monitor, which has not been instantiated (in other words is null) hence, when calling m.put() you get NullPointerException. Please also mind, that using Thread.sleep(1000) is not an accurate way of measuring time.
If I may, please use recommended for Java class naming conventions - some of your names use lower case, while other don't which is confusing to the reader.
Daniel

Problem with threads within applet

Hello,
I got an applet, inside this applet I have a singleton, inside this singleton I have a thread.
this thread is running in endless loop.
he is doing something and go to sleep on and on.
the problem is,
when I refresh my IE6 browser I see more than 1 thread.
for debug matter, I did the following things:
inside the thread, sysout every time he goes to sleep.
sysout in the singleton constructor.
sysout in the singleton destructor.
the output goes like this:
when refresh the page, the singleton constructor loading but not every refresh, sometimes I see the constructor output and sometimes I dont.
The thread inside the singleton is giving me the same output, sometime I see more than one thread at a time and sometimes I dont.
The destructor never works (no output there).
I don't understand what is going on.
someone can please shed some light?
thanks.
btw. I am working with JRE 1.1
this is very old and big applet and I can't convert it to something new.

Ooops. sorry!
I did.
     public void start() {
     public void stop() {
     public void destroy() {
          try {
               resetAll();
               Configuration.closeConnection();
               QuoteItem.closeConnection();
          } finally {
               try {
                    super.finalize();
               } catch (Throwable e) {
                    e.printStackTrace();
     }

Problem with Threads and "plase wait..."-Window

Hi everyone,
I have a problem that I'm not able to solve in any way... I have a time-consuming task (a file decryption) which I execute in a separate thread; I've used the SwingWorker class, like suggested by sun-tutorial, and it works right. The problem is that I have to wait that the decryption have finished before continuing with program-execution. Therefore I would like to display a "please wait"-window while the task runs. I've tryed all the possible ways I know but the problem is always the same: the waitWindow is displayed empty, the bounds are painted but the contents no; it's only painted when the decrypt-task has finished. Please help me, I have no more resources....
decrypt-file code:
public class DecryptFile {
private String cryptedFileNameAndPath;
private ByteArrayInputStream resultStream = null;
// need for progress
private int lengthOfTask;
private int current = -1;
private String statMessage;
public DecryptFile(String encZipFileNameAndPath) {
    cryptedFileNameAndPath = encZipFileNameAndPath;
    //Compute length of task...
    // 0 for indeterminate
    lengthOfTask = 0;
public ByteArrayInputStream getDecryptedInputStream() {
    return this.resultStream;
   * Called from ProgressBarDemo to start the task.
public void go() {
    current = -1;
    final SwingWorker worker = new SwingWorker() {
      public Object construct() {
        return new ActualTask();
    worker.start();
   * Called from ProgressBarDemo to find out how much work needs
   * to be done.
public int getLengthOfTask() {
    return lengthOfTask;
   * Called from ProgressBarDemo to find out how much has been done.
public int getCurrent() {
    return current;
public void stop() {
    current = lengthOfTask;
   * Called from ProgressBarDemo to find out if the task has completed.
public boolean done() {
    if (current >= lengthOfTask)
      return true;
    else
      return false;
public String getMessage() {
    return statMessage;
   * The actual long running task. This runs in a SwingWorker thread.
class ActualTask {
    ActualTask () {
      current = -1;
      statMessage = "";
      resultStream = AIUtil.getInputStreamFromEncZip(cryptedFileNameAndPath); //here the decryption happens
      current = 0;
      statMessage = "";
}The code that calls decryption and displays waitWindow
      final WaitSplash wS = new WaitSplash("Please wait...");
      final DecryptFile cryptedTemplate = new DecryptFile (this.templateFile);
      cryptedTemplate.go();
      while (! cryptedTemplate.done()) {
        try {
          wait();
        } catch (Exception e) { }
      this.templateInputStream = cryptedTemplate.getDecryptedInputStream();
      wS.close();Thanks, thanks, thanks in advance!
Edoardo

Maybe you can try setting the priority of the long-running thread to be lower? so that the UI will be more responsive...

Problem with threads in j2me

im using jdk 1.6 with java wtk 2.1
ya i know..
2.1 is a jdk1.4 source
but im using souce as 1.4 during compiliation so thats not the prob
this is my code
package org.learn;
import javax.microedition.midlet.MIDlet;
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.Display;
public class thtest extends MIDlet
Thread t;
public void startApp()
Alert a=new Alert("hello");
a.setString("hello");
Alert b=new Alert("world");
b.setString("world");
Display d = Display.getDisplay(this );
d.setCurrent(a);
t=Thread.currentThread();
try{
t.sleep(10000);
catch (Exception e){}
d.setCurrent(b);
public void pauseApp()
public void destroyApp(boolean unconditional)
its just supposed to pause between the alerts using threads
however when i run it using the wtk, the emulator run properly but when i launch the app, it stops executing giving me this:
"Error verifying method org/learn/thtest startApp()V
Approximate bytecode offset 49: Inconsistent or missing stackmap at target
%the stack info%
Execution completed.
437782 bytecodes executed
9 thread switches
486 classes in the system (including system classes)
2506 dynamic objects allocated (73832 bytes)
2 garbage collections (60652 bytes collected)
Execution completed.
437782 bytecodes executed
9 thread switches
486 classes in the system (including system classes)
ALERT: java/lang/VerifyError: org/learn/thtest.
2506 dynamic objects allocated (73832 bytes)
2 garbage collections (60652 bytes collected)
please can someone help me out with this, is it an error on my part or do i have to set some option.

Hi gandalf123,
First, Thread.sleep is a static method, so you don't need to create a Thread object to use it.
I think the problem is due to the fact you don't preverify your midlet.
More over, you don't need to double post your question.

Problem with threads hanging

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