在使用Quartz进行任务调度时，需要用到Cron表达式，有时候在设置完Cron表达式之后，需要知道此cron表达式对应的最近几次执行的具体时间，我这里提供了一个方法来获取最近几次的运行时间。

package com.declan;import java.text.SimpleDateFormat;import java.util.Date;import org.quartz.CronExpression;import org.quartz.CronScheduleBuilder;import org.quartz.CronTrigger;import org.quartz.TriggerBuilder;/** * 通过Cron表达式获取近5次的执行时间 * @author Declan * */public class GetScheduleTimeOfCron {			public static void main(String[] args) {		System.out.println(getCronSchdule("1 3 8 * * ?"));	}			 /**     * 根据Cron表达式获取任务最近5次的执行时间     * @param cron     * @return     */    public static String getCronSchdule(String cron){		String timeSchdule="";		if(!CronExpression.isValidExpression(cron)){			return "Cron is Illegal!";		}		try {			CronTrigger trigger = TriggerBuilder.newTrigger().withIdentity("Caclulate Date").withSchedule(CronScheduleBuilder.cronSchedule(cron)).build();			Date time0 = trigger.getStartTime();			Date time1 = trigger.getFireTimeAfter(time0);			Date time2 = trigger.getFireTimeAfter(time1);			Date time3 = trigger.getFireTimeAfter(time2);			Date time4 = trigger.getFireTimeAfter(time3);			Date time5 = trigger.getFireTimeAfter(time4);			SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");			StringBuilder timeBuilder=new StringBuilder();			timeBuilder			.append(format.format(time1))			.append("\n")			.append(format.format(time2))			.append("\n")			.append(format.format(time3))			.append("\n")			.append(format.format(time4))			.append("\n")			.append(format.format(time5));			timeSchdule=timeBuilder.toString();		} catch (Exception e) {			timeSchdule="unKnow Time!";		}		return timeSchdule;	}  /**     * 根据Cron表达式获取任务最近 几次的执行时间     * @param cron  cron表达式     * @param count 次数     * @return     */    public static List
    
      getCronSchdule(String cron, int count){    	List
     
       retList = new ArrayList
      
       ();		if(!CronExpression.isValidExpression(cron)){			//Cron表达式不正确			return retList;		}		try {			CronTrigger trigger = TriggerBuilder.newTrigger().withIdentity("Caclulate Date").withSchedule(CronScheduleBuilder.cronSchedule(cron)).build();			SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");			Date startTime = trigger.getStartTime();			for (int i = 0; i < count; i++) {				Date time = trigger.getFireTimeAfter(startTime);				retList.add(format.format(time ));				startTime = time;			}		} catch (Exception e) {			logger.error("", e);		}		return retList;	}}
      
     
    

运行后的结果

2018-04-20 08:03:012018-04-21 08:03:012018-04-22 08:03:012018-04-23 08:03:012018-04-24 08:03:01