Java死锁

产生死锁原因：

1.系统资源不足.

2.进程运行推进的顺序不合适

3.资源分配不当

import java.util.concurrent.TimeUnit;

class HoldLockThread implements Runnable {
    private String lockA;
    private String lockB;

    public HoldLockThread(String lockA, String lockB) {
        this.lockA = lockA;
        this.lockB = lockB;
    }

    @Override
    public void run() {
        synchronized (lockA) {
            System.out.println(Thread.currentThread().getName() + "	 自己持有：" + lockA +
                    "	 尝试获得：" + lockB);
            try {
                TimeUnit.SECONDS.sleep(2);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

            synchronized (lockB) {
                System.out.println(Thread.currentThread().getName() + "	 自己持有：" + lockB + "	 尝试获得：" + lockA);
            }
        }
    }
}

public class DeadLockDemo {
    public static void main(String[] args) {
        String lockA = "lockA";
        String lockB="lockB";
        new Thread(new HoldLockThread(lockA,lockB),"ThreadAA").start();
        new Thread(new HoldLockThread(lockB,lockA),"ThreadBB").start();
    }
}

　　解决：

 

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