package com.bjpowernode.threads;
public class ThreadDeadlock {
  public static void main(String[] args) throws InterruptedException {
    Object obj1 = new Object();
    Object obj2 = new Object();
    Object obj3 = new Object();
    Thread t1 = new Thread(new SyncThread(obj1, obj2), "t1");
    Thread t2 = new Thread(new SyncThread(obj2, obj3), "t2");
    Thread t3 = new Thread(new SyncThread(obj3, obj1), "t3");
    t1.start();
    Thread.sleep(5000);
    t2.start();
    Thread.sleep(5000);
    t3.start();
  }
}
class SyncThread implements Runnable{
  private Object obj1;
  private Object obj2;
  public SyncThread(Object o1, Object o2){
    this.obj1=o1;
    this.obj2=o2;
  }
  @Override
  public void run() {
    String name = Thread.currentThread().getName();
    System.out.println(name + " acquiring lock on "+obj1);
    synchronized (obj1) {
     System.out.println(name + " acquired lock on "+obj1);
     work();
     System.out.println(name + " acquiring lock on "+obj2);
     synchronized (obj2) {
      System.out.println(name + " acquired lock on "+obj2);
      work();
    }
     System.out.println(name + " released lock on "+obj2);
    }
    System.out.println(name + " released lock on "+obj1);
    System.out.println(name + " finished execution.");
  }
  private void work() {
    try {
      Thread.sleep(30000);
    } catch (InterruptedException e) {
      e.printStackTrace();
    }
  }
}

 2012-12-27 19:08:34
Full thread dump Java HotSpot(TM) 64-Bit Server VM (23.5-b02 mixed mode):
 "Attach Listener" daemon prio=5 tid=0x00007fb0a2814000 nid=0x4007 waiting on condition [0x0000000000000000]
  java.lang.Thread.State: RUNNABLE
"DestroyJavaVM" prio=5 tid=0x00007fb0a2801000 nid=0x1703 waiting on condition [0x0000000000000000]
  java.lang.Thread.State: RUNNABLE
"t3" prio=5 tid=0x00007fb0a204b000 nid=0x4d07 waiting for monitor entry [0x000000015d971000]
  java.lang.Thread.State: BLOCKED (on object monitor)
  at com.bjpowernode.threads.SyncThread.run(ThreadDeadlock.java:41)
  - waiting to lock <0x000000013df2f658> (a java.lang.Object)
  - locked <0x000000013df2f678> (a java.lang.Object)
  at java.lang.Thread.run(Thread.java:722)
"t2" prio=5 tid=0x00007fb0a1073000 nid=0x4207 waiting for monitor entry [0x000000015d209000]
  java.lang.Thread.State: BLOCKED (on object monitor)
  at com.bjpowernode.threads.SyncThread.run(ThreadDeadlock.java:41)
  - waiting to lock <0x000000013df2f678> (a java.lang.Object)
  - locked <0x000000013df2f668> (a java.lang.Object)
  at java.lang.Thread.run(Thread.java:722)
"t1" prio=5 tid=0x00007fb0a1072000 nid=0x5503 waiting for monitor entry [0x000000015d86e000]
  java.lang.Thread.State: BLOCKED (on object monitor)
  at com.bjpowernode.threads.SyncThread.run(ThreadDeadlock.java:41)
  - waiting to lock <0x000000013df2f668> (a java.lang.Object)
  - locked <0x000000013df2f658> (a java.lang.Object)
  at java.lang.Thread.run(Thread.java:722)
"Service Thread" daemon prio=5 tid=0x00007fb0a1038000 nid=0x5303 runnable [0x0000000000000000]
  java.lang.Thread.State: RUNNABLE
"C2 CompilerThread1" daemon prio=5 tid=0x00007fb0a1037000 nid=0x5203 waiting on condition [0x0000000000000000]
  java.lang.Thread.State: RUNNABLE
"C2 CompilerThread0" daemon prio=5 tid=0x00007fb0a1016000 nid=0x5103 waiting on condition [0x0000000000000000]
  java.lang.Thread.State: RUNNABLE
"Signal Dispatcher" daemon prio=5 tid=0x00007fb0a4003000 nid=0x5003 runnable [0x0000000000000000]
  java.lang.Thread.State: RUNNABLE
"Finalizer" daemon prio=5 tid=0x00007fb0a4800000 nid=0x3f03 in Object.wait() [0x000000015d0c0000]
  java.lang.Thread.State: WAITING (on object monitor)
  at java.lang.Object.wait(Native Method)
  - waiting on <0x000000013de75798> (a java.lang.ref.ReferenceQueue$Lock)
  at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:135)
  - locked <0x000000013de75798> (a java.lang.ref.ReferenceQueue$Lock)
  at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:151)
  at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:177)
"Reference Handler" daemon prio=5 tid=0x00007fb0a4002000 nid=0x3e03 in Object.wait() [0x000000015cfbd000]
  java.lang.Thread.State: WAITING (on object monitor)
  at java.lang.Object.wait(Native Method)
  - waiting on <0x000000013de75320> (a java.lang.ref.Reference$Lock)
  at java.lang.Object.wait(Object.java:503)
  at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:133)
  - locked <0x000000013de75320> (a java.lang.ref.Reference$Lock)
"VM Thread" prio=5 tid=0x00007fb0a2049800 nid=0x3d03 runnable 
"GC task thread#0 (ParallelGC)" prio=5 tid=0x00007fb0a300d800 nid=0x3503 runnable 
"GC task thread#1 (ParallelGC)" prio=5 tid=0x00007fb0a2001800 nid=0x3603 runnable 
"GC task thread#2 (ParallelGC)" prio=5 tid=0x00007fb0a2003800 nid=0x3703 runnable 
"GC task thread#3 (ParallelGC)" prio=5 tid=0x00007fb0a2004000 nid=0x3803 runnable 
"GC task thread#4 (ParallelGC)" prio=5 tid=0x00007fb0a2005000 nid=0x3903 runnable 
"GC task thread#5 (ParallelGC)" prio=5 tid=0x00007fb0a2005800 nid=0x3a03 runnable 
"GC task thread#6 (ParallelGC)" prio=5 tid=0x00007fb0a2006000 nid=0x3b03 runnable 
"GC task thread#7 (ParallelGC)" prio=5 tid=0x00007fb0a2006800 nid=0x3c03 runnable 
"VM Periodic Task Thread" prio=5 tid=0x00007fb0a1015000 nid=0x5403 waiting on condition 
JNI global references: 114
Found one Java-level deadlock:
=============================
"t3":
 waiting to lock monitor 0x00007fb0a1074b08 (object 0x000000013df2f658, a java.lang.Object),
 which is held by "t1"
"t1":
 waiting to lock monitor 0x00007fb0a1010f08 (object 0x000000013df2f668, a java.lang.Object),
 which is held by "t2"
"t2":
 waiting to lock monitor 0x00007fb0a1012360 (object 0x000000013df2f678, a java.lang.Object),
 which is held by "t3"
Java stack information for the threads listed above:
===================================================
"t3":
  at com.bjpowernode.threads.SyncThread.run(ThreadDeadlock.java:41)
  - waiting to lock <0x000000013df2f658> (a java.lang.Object)
  - locked <0x000000013df2f678> (a java.lang.Object)
  at java.lang.Thread.run(Thread.java:722)
"t1":
  at com.bjpowernode.threads.SyncThread.run(ThreadDeadlock.java:41)
  - waiting to lock <0x000000013df2f668> (a java.lang.Object)
  - locked <0x000000013df2f658> (a java.lang.Object)
  at java.lang.Thread.run(Thread.java:722)
"t2":
  at com.bjpowernode.threads.SyncThread.run(ThreadDeadlock.java:41)
  - waiting to lock <0x000000013df2f678> (a java.lang.Object)
  - locked <0x000000013df2f668> (a java.lang.Object)
  at java.lang.Thread.run(Thread.java:722)
Found 1 deadlock.

public void run() {
  String name = Thread.currentThread().getName();
  System.out.println(name + " acquiring lock on " + obj1);
  synchronized (obj1) {
    System.out.println(name + " acquired lock on " + obj1);
    work();
  }
  System.out.println(name + " released lock on " + obj1);
  System.out.println(name + " acquiring lock on " + obj2);
  synchronized (obj2) {
    System.out.println(name + " acquired lock on " + obj2);
    work();
  }
  System.out.println(name + " released lock on " + obj2);
 
  System.out.println(name + " finished execution.");
}