请问我这个死锁写的有什么问题吗？

Question

看得视频，跟着敲了一遍，是想写个死锁，但是能执行成功，麻烦帮看看为什么？

public class TestDeadLock implements Runnable {
    public int flag = 1;
    static Object o1 = new Object();
    static Object o2 = new Object();

    public void run () {
        System.out.println("flag=" + flag);

        if (flag == 1) {
            synchronized (o1) {
                try {
                    Thread.sleep(5000);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }

            synchronized (o2) {
                System.out.println(1);
            }
        }

        if (flag == 0) {
            synchronized (o2) {
                try {
                    Thread.sleep(5000);
                } catch (Exception e) {
                    e.printStackTrace();
                }

                synchronized (o1) {
                    System.out.println(0);
                }
            }
        }
    }

    public static void main(String[] args) {
        TestDeadLock td1 = new TestDeadLock();
        TestDeadLock td2 = new TestDeadLock();

        td1.flag = 1;
        td2.flag = 0;

        Thread t1 = new Thread(td1);
        Thread t2 = new Thread(td2);

        t1.start();
        t2.start();
    }
}

Answer 1

经过朋友指点，问题找到了
if (flag == 1) 这个逻辑里，o1与o2对象，没有产生依赖关系。

修改为后

public class TestDeadLock implements Runnable {
    public int flag = 1;
    static Object o1 = new Object();
    static Object o2 = new Object();

    public void run () {
        System.out.println("flag=" + flag);

        if (flag == 1) {
            synchronized (o1) {
                try {
                    Thread.sleep(5000);
                } catch (Exception e) {
                    e.printStackTrace();
                }

                synchronized (o2) {
                       System.out.println(1);
                }
            }
        }

        if (flag == 0) {
            synchronized (o2) {
                try {
                    Thread.sleep(5000);
                } catch (Exception e) {
                    e.printStackTrace();
                }

                synchronized (o1) {
                    System.out.println(0);
                }
            }
        }
    }

    public static void main(String[] args) {
        TestDeadLock td1 = new TestDeadLock();
        TestDeadLock td2 = new TestDeadLock();

        td1.flag = 1;
        td2.flag = 0;

        Thread t1 = new Thread(td1);
        Thread t2 = new Thread(td2);

        t1.start();
        t2.start();
    }
}