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Problem: Eine Java-Anwendung klemmt (vermutlich aufgrund eines Dead-Locks) und man weiss nicht, an welcher Stelle im Code. http://www.weblogic.com/docs51/techsupport/threaddump.html lieferte mir die triviale Lösung mit Java-Bord-Mitteln: Einfach dem Prozess ein SIGQUIT senden. Da hätte ich auch selbst drauf kommen können ;)

public class Test
{
  public static void main(String[] args) throws Exception
  {
    Thread.sleep(20000l);
  }
}

$> javac Test.java
$> java Test
$> kill -3 `pidof java`

Full thread dump Java HotSpot(TM) Client VM (1.4.2_04-b05 mixed mode):

"Signal Dispatcher" daemon prio=1 tid=0x0809f7d8 nid=0x1f99 runnable [0..0]

"JDWP Command Reader" daemon prio=1 tid=0x0809de40 nid=0x1f99 runnable [0..0]

"JDWP Event Helper Thread" daemon prio=1 tid=0x0809cfd8 nid=0x1f99 runnable [0..0]

"JDWP Transport Listener: dt_socket" daemon prio=1 tid=0x0809c408 nid=0x1f99 runnable [0..4d0335e0]

"Finalizer" daemon prio=1 tid=0x08095a00 nid=0x1f99 in Object.wait() [4cf22000..4cf2287c]
at java.lang.Object.wait(Native Method)
- waiting on <0x44d20490> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:111)
- locked <0x44d20490> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:127)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)

"Reference Handler" daemon prio=1 tid=0x08094d90 nid=0x1f99 in Object.wait() [4cea1000..4cea187c]
at java.lang.Object.wait(Native Method)
- waiting on <0x44d20380> (a java.lang.ref.Reference$Lock)
at java.lang.Object.wait(Object.java:429)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:115)
- locked <0x44d20380> (a java.lang.ref.Reference$Lock)

"main" prio=1 tid=0x08052ca8 nid=0x1f99 waiting on condition [bfffc000..bfffce8c]
at java.lang.Thread.sleep(Native Method)
at Test.main(Test.java:7)

"VM Thread" prio=1 tid=0x08093a90 nid=0x1f99 runnable

"VM Periodic Task Thread" prio=1 tid=0x080a22f8 nid=0x1f99 waiting on condition
"Suspend Checker Thread" prio=1 tid=0x0809edc0 nid=0x1f99 runnable