通过jvm 查看死锁

时间:2021-02-10 08:30:47

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();
}
}
}