java简单实现异步队列:使用生产者与消费者模型

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package com.yunshouhu;

import java.util.concurrent.*;

//java简单实现异步队列:使用生产者与消费者模型
public class MyAsynQueue {

	// http://www.importnew.com/22519.html
	// 模拟消息队列订阅者 同时4个线程处理，任务提交者
	private static final ThreadPoolExecutor THREAD_POOL = (ThreadPoolExecutor) Executors.newFixedThreadPool(4);
	// 模拟消息队列生产者,单一线程， 处理者
	private static final ScheduledExecutorService SCHEDULED_EXECUTOR_SERVICE = Executors.newSingleThreadScheduledExecutor();
	
	// 用于判断是否关闭订阅
	private static volatile boolean isClose = false;
	static int taskId=0;
	public static void main(String[] args) throws InterruptedException {
		//保存任务队列
		BlockingQueue<String> queue = new ArrayBlockingQueue<String>(100);
		producer(queue);
		consumer(queue);
		exitALl();
		System.out.println("all finish!");
	}
	

	private static boolean exitALl() {
		if(taskId>10)
		{
			
			THREAD_POOL.shutdown();
			SCHEDULED_EXECUTOR_SERVICE.shutdown();
			return true;
		}else{
			return false;
		}
	}


	// 模拟消息队列生产者
	private static void producer(final BlockingQueue queue) {

		// 每200毫秒向队列中放入一个消息
		SCHEDULED_EXECUTOR_SERVICE.scheduleAtFixedRate(new Runnable() {
			public void run() {
				taskId++;
				queue.offer("taskId="+taskId);
				//exitALl();
				
			}
		}, 0L, 200L, TimeUnit.MILLISECONDS);
	}

	// 模拟消息队列消费者 生产者每秒生产5个 消费者4个线程消费1个1秒 每秒积压1个
	private static void consumer(final BlockingQueue queue) throws InterruptedException {
		//while (!isClose) 
		while(true)
		{
			
			// 从队列中拿到消息
			final String msg = (String) queue.take();
			// 放入线程池处理
			if (!THREAD_POOL.isShutdown()) {
				THREAD_POOL.execute(new Runnable() {
					public void run() {
						try {
							
							TimeUnit.MILLISECONDS.sleep(500L);
							System.out.println(msg+" 任务处理完毕！");
							
							
						} catch (InterruptedException e) {
							e.printStackTrace();
						}
					}
				});
			}
			getPoolBacklogSize();
			if(exitALl())
			{
				break;
			}
			
		}
	}

	// 查看线程池堆积消息个数
	private static long getPoolBacklogSize() {
		long backlog = THREAD_POOL.getTaskCount() - THREAD_POOL.getCompletedTaskCount();
		System.out.println(String.format("[%s]THREAD_POOL 积压的任务:%s", System.currentTimeMillis(), backlog));
		return backlog;
	}

	
}