FULL PRODUCT VERSION :
C:\thilak>"C:\Program Files\Java\jdk1.6.0_02\bin\java.exe" -version
java version "1.6.0_02"
Java(TM) SE Runtime Environment (build 1.6.0_02-b06)
Java HotSpot(TM) Client VM (build 1.6.0_02-b06, mixed mode, sharing)


ADDITIONAL OS VERSION INFORMATION :
C:\thilak>ver

Microsoft Windows XP [Version 5.1.2600]

EXTRA RELEVANT SYSTEM CONFIGURATION :
This bug is reproducable with jdk1.5.0_08 as well, and on the GNU/Linux system also, where it was first detected.

A DESCRIPTION OF THE PROBLEM :
Below is reproduced a program that, on execution, deadlocks the executing JVM: The file-name is called "Dl.java".


C:\thilak>"C:\Program Files\Java\jdk1.6.0_02\bin\javac.exe" Dl.java
Dl.java:28: warning: sun.reflect.annotation.AnnotationType is Sun proprietary API and may be removed in a future release
AnnotationType test = AnnotationType.getInstance (Class.forName(className));
^
Dl.java:28: warning: sun.reflect.annotation.AnnotationType is Sun proprietary API and may be removed in a future release
AnnotationType test = AnnotationType.getInstance (Class.forName(className));
                      ^
2 warnings

C:\thilak>"C:\Program Files\Java\jdk1.6.0_02\bin\java.exe" Dl Test
2007-07-28 13:25:08
Full thread dump Java HotSpot(TM) Client VM (1.6.0_02-b06 mixed mode, sharing):

"DestroyJavaVM" prio=6 tid=0x002a5c00 nid=0xa74 waiting on condition [0x00000000..0x0090fd4c]
   java.lang.Thread.State: RUNNABLE

"Thread-1" prio=6 tid=0x02a91c00 nid=0x16b0 waiting for monitor entry [0x02e6f000..0x02e6fb14]
   java.lang.Thread.State: BLOCKED (on object monitor)
        at java.lang.Class.initAnnotationsIfNecessary(Class.java:3069)
        - waiting to lock <0x26995b40> (a java.lang.Class for Test)
        at java.lang.Class.getAnnotation(Class.java:3029)
        at sun.reflect.annotation.AnnotationType.<init>(AnnotationType.java:113)
        at sun.reflect.annotation.AnnotationType.getInstance(AnnotationType.java:66)
        - locked <0x26996d18> (a java.lang.Class for sun.reflect.annotation.AnnotationType)
        at Dl$Thread2.run(Dl.java:28)

"Thread-0" prio=6 tid=0x02a90c00 nid=0x1254 waiting for monitor entry [0x02e1f000..0x02e1fb94]
   java.lang.Thread.State: BLOCKED (on object monitor)
        at sun.reflect.annotation.AnnotationType.getInstance(AnnotationType.java:63)
        - waiting to lock <0x26996d18> (a java.lang.Class for sun.reflect.annotation.AnnotationType)
        at sun.reflect.annotation.AnnotationParser.parseAnnotation(AnnotationParser.java:202)
        at sun.reflect.annotation.AnnotationParser.parseAnnotations2(AnnotationParser.java:69)
        at sun.reflect.annotation.AnnotationParser.parseAnnotations(AnnotationParser.java:52)
        at java.lang.Class.initAnnotationsIfNecessary(Class.java:3072)
        - locked <0x26995b40> (a java.lang.Class for Test)
        at java.lang.Class.getAnnotations(Class.java:3052)
        at Dl$Thread1.run(Dl.java:16)

"Low Memory Detector" daemon prio=6 tid=0x02a7c800 nid=0x920 runnable [0x00000000..0x00000000]
   java.lang.Thread.State: RUNNABLE

"CompilerThread0" daemon prio=10 tid=0x02a77c00 nid=0x10e0 waiting on condition [0x00000000..0x02d2f91c]
   java.lang.Thread.State: RUNNABLE

"Attach Listener" daemon prio=10 tid=0x02a76800 nid=0xd4c runnable [0x00000000..0x00000000]
   java.lang.Thread.State: RUNNABLE

"Signal Dispatcher" daemon prio=10 tid=0x02a75c00 nid=0x15e4 waiting on condition [0x00000000..0x00000000]
   java.lang.Thread.State: RUNNABLE

"Finalizer" daemon prio=8 tid=0x02a6dc00 nid=0xeb4 in Object.wait() [0x02c3f000..0x02c3fa94]
   java.lang.Thread.State: WAITING (on object monitor)
        at java.lang.Object.wait(Native Method)
        - waiting on <0x22990b38> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:116)
        - locked <0x22990b38> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:132)
        at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)

"Reference Handler" daemon prio=10 tid=0x02a6cc00 nid=0x7c4 in Object.wait() [0x02bef000..0x02befb14]
   java.lang.Thread.State: WAITING (on object monitor)
        at java.lang.Object.wait(Native Method)
        - waiting on <0x22990a38> (a java.lang.ref.Reference$Lock)
        at java.lang.Object.wait(Object.java:485)
        at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:116)
        - locked <0x22990a38> (a java.lang.ref.Reference$Lock)

"VM Thread" prio=10 tid=0x02a63c00 nid=0xc0c runnable

"VM Periodic Task Thread" prio=10 tid=0x02a7e000 nid=0x1d8 waiting on condition

JNI global references: 571


Found one Java-level deadlock:
=============================
"Thread-1":
  waiting to lock monitor 0x02a6ee5c (object 0x26995b40, a java.lang.Class),
  which is held by "Thread-0"
"Thread-0":
  waiting to lock monitor 0x02a6eec4 (object 0x26996d18, a java.lang.Class),
  which is held by "Thread-1"

Java stack information for the threads listed above:
===================================================
"Thread-1":
        at java.lang.Class.initAnnotationsIfNecessary(Class.java:3069)
        - waiting to lock <0x26995b40> (a java.lang.Class for Test)
        at java.lang.Class.getAnnotation(Class.java:3029)
        at sun.reflect.annotation.AnnotationType.<init>(AnnotationType.java:113)
        at sun.reflect.annotation.AnnotationType.getInstance(AnnotationType.java:66)
        - locked <0x26996d18> (a java.lang.Class for sun.reflect.annotation.AnnotationType)
        at Dl$Thread2.run(Dl.java:28)
"Thread-0":
        at sun.reflect.annotation.AnnotationType.getInstance(AnnotationType.java:63)
        - waiting to lock <0x26996d18> (a java.lang.Class for sun.reflect.annotation.AnnotationType)
        at sun.reflect.annotation.AnnotationParser.parseAnnotation(AnnotationParser.java:202)
        at sun.reflect.annotation.AnnotationParser.parseAnnotations2(AnnotationParser.java:69)
        at sun.reflect.annotation.AnnotationParser.parseAnnotations(AnnotationParser.java:52)
        at java.lang.Class.initAnnotationsIfNecessary(Class.java:3072)
        - locked <0x26995b40> (a java.lang.Class for Test)
        at java.lang.Class.getAnnotations(Class.java:3052)
        at Dl$Thread1.run(Dl.java:16)

Found 1 deadlock.


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Copy the java code from below into a text file called Dl.java.
Compile it through using the javac Comnpiler to fetch Dl.class.
Copy another peice of code below into a file called Test.java.
Compile it through the use of javac compiler to fetch the file Test.class.

On the command line execute the command: "java Dl Test".
Often the command will just hang, implying that the executing jvm has deadlocked.
Ctrl-break fetches the output pasted in the description above.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The jvm neednot deadlock as it sometimes does when executing this otherwise perfectly legal, and well-formed java-program.
ACTUAL -
See description above.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
See description above.

REPRODUCIBILITY :
This bug can be reproduced often.

---------- BEGIN SOURCE ----------
Dl.java:
import java.lang.annotation.Annotation;
import sun.reflect.annotation.*;
public class Dl {
    public Dl (String s) {
        new Thread1(s).start();
        new Thread2(s).start();
    }
    public static void main(String[] args) {
        Dl dl = new Dl(args[0]);
    }
    class Thread1 extends Thread {
        String className;
        public Thread1 (String name) { className = name; }
        public void run() {
            try {
                Annotation[] annArray = Class.forName(className).getAnnotations();
                for (Annotation a: annArray) System.out.println (a);
            } catch (Exception e) {
                System.out.printf ("Thread1 failes: %s %n", e.getCause());
            }
        }
    }
    class Thread2 extends Thread {
        String className;
        public Thread2 (String name) { className = name; }
        public void run() {
            try {
                 AnnotationType test = AnnotationType.getInstance (Class.forName(className));
                 System.out.println (test);
            } catch (Exception e) {
                 System.out.printf ("Thread2 failes: %s %n", e.getCause());
            }
        }
    }
}

Test.java:
import java.lang.annotation.*;
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface Test {}

---------- END SOURCE ----------