Java利用DelayQueue实现延迟任务代码实例

package com.dack.test;
import java.util.Calendar;
import java.util.concurrent.DelayQueue;
import java.util.concurrent.Delayed;
import java.util.concurrent.TimeUnit;
public class DelayedTask implements Delayed {
	public static DelayQueue<DelayedTask> queue;
	// 任务的执行时间
	private int executeTime = 0;
	// 业务需要的参数
	private String outStr = "";
	public static void main(String[] args) {
		DelayedTask.queue = new DelayQueue<DelayedTask>();
		// 可有可无
		DelayedTask.queue.add(new DelayedTask(2, "hello"));
		System.out.println(System.currentTimeMillis() + "服务启动");
		while (true) {
			DelayedTask delayedTask = DelayedTask.queue.poll();
			if (delayedTask != null) {
				String os = delayedTask.getOutStr();
				//可以随时添加新的延时任务
				DelayedTask.queue.add(new DelayedTask(2, "hello"));
				System.out.println(System.currentTimeMillis() + " 消费服务 ,传参" + os);
			}
		}
	}
	public DelayedTask(int delay) {
		Calendar calendar = Calendar.getInstance();
		calendar.add(Calendar.SECOND, delay);
		this.executeTime = (int) (calendar.getTimeInMillis());
	}
	// 业务所需的参数构造方法
	public DelayedTask(int delay, String str) {
		Calendar calendar = Calendar.getInstance();
		calendar.add(Calendar.SECOND, delay);
		this.executeTime = (int) (calendar.getTimeInMillis());
		this.outStr = str;
	}
	/**
	 * 元素在队列中的剩余时间
	 * 
	 * @param unit
	 * @return
	 */
	@Override
	public long getDelay(TimeUnit unit) {
		Calendar calendar = Calendar.getInstance();
		return executeTime - (calendar.getTimeInMillis());
	}
	/**
	 * 元素排序
	 * 
	 * @param o
	 * @return
	 */
	@Override
	public int compareTo(Delayed o) {
		long val = this.getDelay(TimeUnit.NANOSECONDS) - o.getDelay(TimeUnit.NANOSECONDS);
		return val == 0 ? 0 : (val < 0 ? -1 : 1);
	}
	public int getExecuteTime() {
		return executeTime;
	}
	public void setExecuteTime(int executeTime) {
		this.executeTime = executeTime;
	}
	public String getOutStr() {
		return outStr;
	}
	public void setOutStr(String outStr) {
		this.outStr = outStr;
	}
}