java-写一个死锁的案例

死锁:线程A持有一个对象a1的互斥锁，又试图获取另外一个对象b1的互斥锁，而线程B正好持有对象a1的互斥锁，并且试图获取对象b1的互斥锁，2个线程相互等待对方的资源而又互相不作出让步。

<span style="font-size:14px;">package com.test;
/**
 * 死锁测试
 * @author mooner
 *
 */
public class DeadThreadLock {
	public static void main(String[] args) {
		String s1 = "a";
		String s2 = "b";
		
		ThreadLock t1 = new ThreadLock(s1,s2);  //持有"a"的互斥锁，尝试获取"b"的互斥锁
		t1.start();
		
		
		ThreadLock t2 = new ThreadLock(s2,s1);  //持有"b"的互斥锁，尝试获取"a"的互斥锁
		t2.start();
			
	}
}

/**
 * 死锁多线程
 * @author mooner
 *
 */
class ThreadLock extends Thread{
	private String s1;
	private String s2;
	public ThreadLock(){
		
	}
	public ThreadLock(String s1,String s2){
		this.s1 = s1;
		this.s2 = s2;
	}
	public void run(){
		synchronized(s1){  //获取s1对象的互斥锁
			System.out.println(Thread.currentThread().getName()  +"持有对象  "+s1+"  的锁");
			try {
				Thread.sleep(4000);  //睡眠4s钟，好在获取s2对象的互斥锁前，另外一个线程开始运行
			} catch (InterruptedException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			System.out.println(Thread.currentThread().getName()  +"尝试获取  "+s2+"  的锁");
			synchronized(s2){  //获取s2对象的互斥锁子
				
			}
		}
	}
}</span>