java队列，很实用，很重要

http://www.iteye.com/topic/519260
有优先级的
http://jiangzhengjun.iteye.com/blog/565275
上面说的比较散乱，用ConcurrentLinkedQueue来做比较好，线程安全的。
package test;

import java.util.PriorityQueue;
import java.util.concurrent.ConcurrentLinkedQueue;

public class QueueTest2
{
    public static void main(String[] args)
    {
       
//        PriorityQueue priorityQueue = new PriorityQueue();
//        priorityQueue.offer("Texas");
//        priorityQueue.offer("Alabama");
//        priorityQueue.offer("California");
//        priorityQueue.offer("Rhode Island");
//        int queueSize = priorityQueue.size();
//        for (int i = 0; i < queueSize; i++)
//        {
//            System.out.println(priorityQueue.poll());
//        }
        ConcurrentLinkedQueue <String> highPriority =  new  ConcurrentLinkedQueue <String>();  //高优先级
        highPriority.add("ddd2");
        highPriority.add("ddd1");
        highPriority.add("ddd3");
        highPriority.add("ddd4");
        System.out.println(highPriority.remove());
        System.out.println(highPriority.remove());
        System.out.println(highPriority.remove());
        System.out.println(highPriority.remove());
       
    }
}