With the following test program, NullPointerException will be
thrown. That is not in line with the API.
http://java.sun.com/javase/6/docs/api/java/lang/Thread.html#getStackTrace()

TP:
----->
public class STNull {
  public static void main(String[] args) throws Exception {
    while(true) {
      Thread t = new Thread();
      t.start();
      StackTraceElement[] stes = t.getStackTrace();
      System.out.println(stes.length);
    }
  }
}
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One of our customers reported NPE would be seen on Linux/EM64T below.

----->
java version "1.5.0_12"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_12-b04)
Java HotSpot(TM) 64-Bit Server VM (build 1.5.0_12-b04, mixed mode)

java version "1.6.0_02"
Java(TM) SE Runtime Environment (build 1.6.0_02-b04)
Java HotSpot(TM) 64-Bit Server VM (build 1.6.0_02-b04, mixed mode)

java version "1.7.0-ea"
Java(TM) SE Runtime Environment (build 1.7.0-ea-b13)
Java HotSpot(TM) 64-Bit Server VM (build 1.7.0-ea-b13, mixed mode)
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I also reproduced this against both jdk 5.0 and jdk 6.0 on my Windows
XP laptop as follows.

----->
$ java -version
java version "1.5.0_10"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_10-b03)
Java HotSpot(TM) Client VM (build 1.5.0_10-b03, mixed mode, sharing)

$ java STNull
0
0
0
0
0
Exception in thread "main" java.lang.NullPointerException
        at STNull.main(STNull.java:7)

$ /g/jdk60/bin/java -version
java version "1.6.0"
Java(TM) SE Runtime Environment (build 1.6.0-b105)
Java HotSpot(TM) Client VM (build 1.6.0-b105, mixed mode)

$ /g/jdk60/bin/java STNull
0
0
0
0
0
0
0
0
Exception in thread "main" java.lang.NullPointerException
        at STNull.main(STNull.java:7)
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