Java一個簡單的死結例子

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內容：一個簡單的死結例子，大概的思路：兩個線程A和B，兩把鎖X和Y，現在A先拿到鎖X，然後sleep()一段時間，我們知道sleep()是不會釋放鎖資源的。然後如果這段時間軸程B拿到鎖Y，也sleep()一段時間的話，那麼等到兩個線程都醒過來的話，那麼將互相等待對方釋放鎖資源而僵持下去，陷入死結。flag的作用就是讓A和B獲得不同的鎖。

public class TestDeadLock {public void run() {MyThread mt = new MyThread();new Thread(mt, "張三").start();new Thread(mt, "李四").start();}class MyThread implements Runnable {private Object o1 = new Object();private Object o2 = new Object();private boolean flag = true;@Overridepublic void run() {if (flag) {flag = false;synchronized (o1) {System.out.println(Thread.currentThread().getName() + " have o1");try {Thread.sleep(100);} catch (InterruptedException e) {e.printStackTrace();}synchronized (o2) {System.out.println(Thread.currentThread().getName() + " have o2");}}} else {flag = true;synchronized (o2) {System.out.println(Thread.currentThread().getName() + " have o2");try {Thread.sleep(100);} catch (InterruptedException e) {e.printStackTrace();}synchronized (o1) {System.out.println(Thread.currentThread().getName() + " have o1");}}}}}public static void main(String[] args) {new TestDeadLock().run();}}

Java一個簡單的死結例子