2023-04-12 ReentrantLock使用注意事项

1.await通常配合while循环使用，防止调用java.util.concurrent.locks.ReentrantLock#lockInterruptibly()方法的情况下发生虚假唤醒的问题

2.ReentrantLock中await和signal必须和相对应的锁配合使用，必须在对应锁的加锁解锁代码中间使用
示例：

        private ReentrantLock tailLock = new ReentrantLock();
        private Condition headWaits = tailLock.newCondition();
        
        private ReentrantLock headLock = new ReentrantLock();
        private Condition tailWaits = headLock.newCondition();
        
        tailLock.lockInterruptibly();
        try {
            long t = TimeUnit.MILLISECONDS.toNanos(timeout);
            while (isFull()) {
                if (t <= 0) {
                    return false;
                }
                t = tailWaits.awaitNanos(t);
            }
            array[tail] = e;
            if (++tail == array.length) {
                tail = 0;
            }
//            size++;
            size.getAndIncrement();

            headLock.lock();
            try {
                headWaits.signal(); // signal()和await()必须配对使用
            } finally {
                headLock.unlock();
            }
            return true;
        } finally {
            tailLock.unlock();
        }