java会释放所有锁吗？

1 年，4 月 Questions & Answers 81

我编写这个程序是为了检查在两个不同对象上持有锁的线程：LOCK_OBJECT和FULL是否在LOCK_OBJECT上使用FULL.wait()进入等待模式。我没想到消费者会得到LOCK_OBJECT锁，但印刷品没有。那么你错过了什么吗

为什么消费者会根据打印的结果获得LOCK_OBJECT锁

这是我的代码：

public class TestSync {

    private volatile Integer amount = 0;
    private final Object LOCK_OBJECT = new Object();
    private final Object FULL = new Object();

    public void doubleSync() throws InterruptedException {
        System.out.println("Producer  trying to get LOCK_OBJECT lock ");
        synchronized (LOCK_OBJECT) {
            System.out.println("Producer get LOCK_OBJECT lock ");
            Print.sleep(3000);
            while (amount >= 0) {
                synchronized (FULL) {
                    System.out.println("full！");
                    FULL.wait();
                }
            }
            System.out.println("continue~");
            amount++;
        }
    }

    public void simpleSync() {
        System.out.println("Consumer trying to get LOCK_OBJECT lock ");
        synchronized (LOCK_OBJECT) {
            System.out.println("Consumer get LOCK_OBJECT lock");
        }
        System.out.println("Consumer release LOCK_OBJECT lock");
    }

    public static void main(String[] args) throws InterruptedException {
        AtomicInteger atomicInteger = new AtomicInteger(0);
        ExecutorService threadPool = Executors.newFixedThreadPool(1, new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                int index = atomicInteger.incrementAndGet();
                System.out.println("create no " + index + " thread");
                Thread t = new Thread(r, "one Thread-" + index);
                return t;
            }
        });
        threadPool.execute(() -> {
            try {
                new TestSync().doubleSync();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        });
        Print.sleep(1000);
        ExecutorService executorService = Executors.newFixedThreadPool(1, new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                int index = atomicInteger.incrementAndGet();
                System.out.println("create no " + index + " thread");
                Thread t = new Thread(r, "two Thread-" + index);
                return t;
            }
        });
        executorService.execute(() -> {
            try {
                new TestSync().simpleSync();
            } catch (Exception e) {
                e.printStackTrace();
            }
        });
    }
}

这是打印结果：

create no 1 thread
sleep 1000
Producer  trying to get LOCK_OBJECT lock 
Producer get LOCK_OBJECT lock 
sleep 3000
create no 2 thread
Consumer trying to get LOCK_OBJECT lock 
Consumer get LOCK_OBJECT lock
Consumer release LOCK_OBJECT lock
full！

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java会释放所有锁吗？

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