[LinkedIn面试]implement the take() and put() of blocking queue

题目如下：

public interface BlockingQueue{    /** Retrieve and remove the head of the queue, waiting if no elements    are present. */    T take();    /** Add the given element to the end of the queue, waiting if necessary    for space to become available. */    void put (T obj);}

看了网上的解答，很不错的解答，从这里来的：Good Solution (with a little tweak) 其中感觉有点错误，看我在代码中的comment

public class BlockingQueue {  private List queue = new LinkedList();  private int  limit = 10;  public BlockingQueue(int limit){    this.limit = limit;  }  public synchronized void enqueue(Object item)  throws InterruptedException  {    while(this.queue.size() == this.limit) {      wait();    }    /** This is what comes from the post, but if you notify here, say a 'dequeue()' is waiting, the size would remain at 0 doesn't it? So I would call notify at the end    if(this.queue.size() == 0) {      notifyAll();    }    **/    this.queue.add(item);    notifyAll();  }  public synchronized Object dequeue()  throws InterruptedException{    while(this.queue.size() == 0){      wait();    }    /** This is what comes from the post, but if you notify here, say a 'enqueue()' is waiting, the size would remain at the limit doesn't it? So I would call notify at the end    if(this.queue.size() == this.limit){      notifyAll();    }    **/    Object ret = this.queue.remove(0);    notifyAll();    return ret;  }}