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();
    }
}