import java.util.LinkedList;public class Stack {public static void main(String[] args) {final Stack stack = new Stack();new Thread("push") {@Overridepublic void run() {for (int i = 0; i < 100; i++) {try {Thread.sleep(10);//to make the deadlock occur} catch (InterruptedException e) {}stack.push("object " + i);}}}.start();new Thread("pop") {@Overridepublic void run() {for (int i = 0; i < 100; i++) {try {System.out.println(stack.pop());} catch (Exception e) {}}}}.start();}LinkedList<Object> list = new LinkedList<Object>();public synchronized void push(Object x) {System.out.println("begin to push " + x);synchronized (list) {list.addLast(x);notify();}System.out.println("end to push " + x);}public synchronized Object pop() throws Exception {System.out.println("begin to pop");synchronized (list) {if (list.size() <= 0) {wait();}return list.removeLast();}}}

begin to pop
begin to push object 0

"pop" prio=6 tid=0x00c00000 nid=0x2b0 in Object.wait() [0x00f9f000]java.lang.Thread.State: WAITING (on object monitor)at java.lang.Object.wait(Native Method)- waiting on <0x27f65648> (a loggerlock.Stack)at java.lang.Object.wait(Object.java:485)at loggerlock.Stack.pop(Stack.java:49)- locked <0x27f65658> (a java.util.LinkedList)- locked <0x27f65648> (a loggerlock.Stack)at loggerlock.Stack$2.run(Stack.java:26)Locked ownable synchronizers:- None"push" prio=6 tid=0x00bfec00 nid=0x14c8 waiting for monitor entry [0x00f4f000]java.lang.Thread.State: BLOCKED (on object monitor)at loggerlock.Stack.push(Stack.java:39)- waiting to lock <0x27f65658> (a java.util.LinkedList)- locked <0x27f65648> (a loggerlock.Stack)at loggerlock.Stack$1.run(Stack.java:16)Locked ownable synchronizers:- None