public class DeadLocak {

    private final Object left = new Object();
    private final Object right = new Object();

    public void leftRight() throws Exception {
        synchronized (left) {
            Thread.sleep(2000);
            synchronized (right) {
                System.out.println("leftRight end!");
            }
        }
    }

    public void rightLeft() throws Exception {
        synchronized (right) {
            Thread.sleep(2000);
            synchronized (left) {
                System.out.println("rightLeft end!");
            }
        }
    }

    public static void main(String[] args) {
        final DeadLocak deadLocak = new DeadLocak();

        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    deadLocak.leftRight();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }).start();

        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    deadLocak.rightLeft();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }
}
 

利用jstack -pid 號檢視發現