ScheduledExecutorService任务定时代码示例

package com.effective.common.concurrent.execute;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
public class Schedule {
	private static DateFormat dateFormat = new SimpleDateFormat("yy-MM-dd HH:mm:ss");
	private static DateFormat dayFormat = new SimpleDateFormat("yy-MM-dd");
	private static ScheduledExecutorService excutor = Executors.newSingleThreadScheduledExecutor();
	/**
   * 按指定频率周期执行某个任务 <br>
   * 初始化延迟0ms开始执行，每隔5ms重新执行一次任务。
   */
	public void fixedRate(){
		excutor.scheduleAtFixedRate(new EchoServer(), //执行线程
		0, //初始化延迟
		5000, //两次开始的执行的最小时间间隔
		TimeUnit.MILLISECONDS //计时单位
		);
	}
	/**
   * 
   */
	public void fixDelay(){
		excutor.scheduleWithFixedDelay(new EchoServer(),//执行线程 
		0, //初始化延迟
		5000, //前一次执行结束到下一次执行开始的间隔时间
		TimeUnit.MILLISECONDS);
	}
	/**
   * 每天晚上8点执行一次
   */
	public void dayOfDelay(String time){
		ScheduledExecutorService executor = Executors.newScheduledThreadPool(1);
		long oneDay = 24 * 60 * 60 * 1000;
		long initDelay = getTimeMillis("20:00:00") - System.currentTimeMillis();
		initDelay = initDelay > 0 ? initDelay : oneDay + initDelay;
		executor.scheduleAtFixedRate( 
		        new EchoServer(), 
		        initDelay, 
		        oneDay, 
		        TimeUnit.MILLISECONDS);
	}
	/**
   * 获取给定时间对应的毫秒数
   * @param string "HH:mm:ss"
   * @return
   */
	private static long getTimeMillis(String time) {
		try {
			Date currentDate = dateFormat.parse(dayFormat.format(new Date()) + " " +time);
			return currentDate.getTime() ;
		}
		catch (ParseException e) {
			e.printStackTrace();
		}
		return 0;
	}
	public static void main(String[] args){
		Schedule schedule = new Schedule();
		schedule.fixedRate();
		schedule.fixDelay();
	}
}