手写阻塞队列

写个阻塞队列~~~

/**
 * 手写阻塞队列
 * ELEGANT
 */
public class MyBlockingQueue {

    // 存储元素
    private final Object[] items;
    private int maxSize;
    private int takeIndex = 0;
    private int putIndex = 0;
    private volatile int size = 0;
    private ReentrantLock lock = new ReentrantLock();
    private Condition takeCondition = lock.newCondition();
    private Condition putCondition = lock.newCondition();

    public MyBlockingQueue(int maxSize) throws Exception {
        if (maxSize < 0){
            throw new Exception("大小不能小于0");
        }
        this.maxSize = maxSize;
        items = new Object[maxSize];
    }

    public Object take(){
        lock.lock();
        Object resp = null;
        try {
            while (size == 0){
                System.out.println("没有东西拿");
                takeCondition.await();
            }
            resp = items[takeIndex];
            items[takeIndex] = null;
            takeIndex = (takeIndex + 1) % items.length;
            size--;
            putCondition.signalAll();
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        } finally {
            lock.unlock();
        }
        return resp;
    }

    public void put(Object x){
        lock.lock();

        try {
            while (size == maxSize){
                System.out.println("空间已满");
                putCondition.await();
            }
            items[putIndex] = x;
            putIndex = (putIndex + 1) % items.length;
            size++;
            takeCondition.signalAll();
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        } finally {
            lock.unlock();
        }
    }


    public static void main(String[] args) throws Exception {
        MyBlockingQueue myBlockingQueue = new MyBlockingQueue(10);

        new Thread(() -> {
            while (true){
                myBlockingQueue.put(10);
            }
        }).start();
        new Thread(() -> {
            while (true){
                System.out.println(myBlockingQueue.take());
            }
        }).start();
    }
}