也做迅雷笔试题

刚开始觉得不难，动手写的时候才发现问题。调试了好多遍才出来结果。上代码：

import java.util.LinkedList;


public class ABC {

	public static void main(String[] args) {
		Lock lock=new Lock();
		MyThread t1=new MyThread("A", lock,10);
		MyThread t2=new MyThread("B", lock,10);
		MyThread t3=new MyThread("C", lock,10);
		new Thread(t1).start();
		new Thread(t2).start();
		new Thread(t3).start();
	}
	
}
//线程
class MyThread implements Runnable{

	String key=null;
	Lock lock=null;
	int num=0;
	public MyThread(String k,Lock l,int n) {
	key=k;
	lock=l;
	num=n;
	}
	@Override
	public void run() {
		while(num>0){
			synchronized (lock) {
				if(key==lock.queue.getFirst())	
				{
				System.out.print(key);
				lock.next();
				num--;
				}}
		}
	}
}
//锁功能
class Lock{
	LinkedList<String>queue;//模仿循环队列
	Lock(){
		queue=new LinkedList<String>();
		queue.add("A");
		queue.add("B");
		queue.add("C");		
	}
	 void next(){
		String h=queue.poll();
		queue.add(h);
	}
	
}

才通过论坛测试，第一次发帖....汗！