Java死锁_动力节点Java学院整理

死锁是两个甚至多个线程被永久阻塞时的一种运行局面，这种局面的生成伴随着至少两个线程和两个或者多个资源。在这里我已写好一个简单的程序，它将会引起死锁方案然后我们就会明白如何分析它。

Java死锁范例

ThreadDeadlock.java

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();    }  }}