/* 目的:自己写一个由于同步嵌套引起的死锁! 思路:多个线程在执行时,某一时刻,0-Thread绑定了LockA锁,1-Thread绑定了LockB锁! 当0-Thread要去绑定LockB锁时 和 1-Thread要去绑定LockA锁时都不能绑定,此时两个线程不能继续进行! */ class Ticket implements Runnable{ public boolean flag; Ticket(boolean flag){ this.flag = flag; } Ticket(){ flag=true; } public void run(){ if(flag){ synchronized(MyLock.lockA){ System.out.println(Thread.currentThread().getName() + " lockA &&--->lockB"); try{ Thread.sleep(100); }catch(InterruptedException e){ } synchronized(MyLock.lockB){ System.out.println(Thread.currentThread().getName() + " lockB"); } } } else{ synchronized(MyLock.lockB){ System.out.println(Thread.currentThread().getName() + " lockB &&--->lockA"); synchronized(MyLock.lockA){ System.out.println(Thread.currentThread().getName() + " lockA"); } } } } } class MyLock{ public static final MyLock lockA = new MyLock(); public static final MyLock lockB = new MyLock(); } public class DeadLockDemo{ public static void main(String[] args){ //虽然new了两个任务对象,但是不影响演示由于同步嵌套引起的死锁情况 // new Thread(new Ticket(true)).start(); // new Thread(new Ticket(false)).start(); /////////////////////////////////////////////////////////// Ticket tt = new Ticket();//只产生一个线程任务!这样写还要控制好sleep的时间才好..... new Thread(tt).start(); try{ Thread.sleep(20); }catch(InterruptedException e){ } tt.flag=false; new Thread(tt).start(); } }