jstack -l jvm_pid

 

运行以下代码之后运行上面命令，可以在控制台上看到死锁。

 

public class DeadLock {    public static String obj1 = "obj1";    public static String obj2 = "obj2";    public static void main(String[] args){        Thread a = new Thread(new Lock1());        Thread b = new Thread(new Lock2());        a.start();        b.start();    }    }class Lock1 implements Runnable{    @Override    public void run(){        try{            System.out.println("Lock1 running");            while(true){                synchronized(DeadLock.obj1){                    System.out.println("Lock1 lock obj1");                    Thread.sleep(3000);//获取obj1后先等一会儿，让Lock2有足够的时间锁住obj2                    synchronized(DeadLock.obj2){                        System.out.println("Lock1 lock obj2");                    }                }            }        }catch(Exception e){            e.printStackTrace();        }    }}class Lock2 implements Runnable{    @Override    public void run(){        try{            System.out.println("Lock2 running");            while(true){                synchronized(DeadLock.obj2){                    System.out.println("Lock2 lock obj2");                    Thread.sleep(3000);                    synchronized(DeadLock.obj1){                        System.out.println("Lock2 lock obj1");                    }                }            }        }catch(Exception e){            e.printStackTrace();        }    }}