Springboot动态定时任务

叁歲伎倆 2022-04-01 05:23 276阅读 0赞

1、动态定时任务

重点在于Trigger。采用Cron格式设置时间，时间存在redis中。比如key为crontime，value设置为10分钟，

即crontime = "0 0/10 \* \* \* ? "。在redis中人为修改时间，任务会在下个定时周期生效，不必重新启动程序。

package com.exm.springmybatis.scheduler.task;
    
    import com.exm.springmybatis.service.RedisServer;
    import lombok.extern.slf4j.Slf4j;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.scheduling.Trigger;
    import org.springframework.scheduling.TriggerContext;
    import org.springframework.scheduling.annotation.SchedulingConfigurer;
    import org.springframework.scheduling.config.ScheduledTaskRegistrar;
    import org.springframework.scheduling.support.CronTrigger;
    import org.springframework.stereotype.Component;
    import org.springframework.util.StringUtils;
    
    import java.util.Date;
    
    /**
     * 重点在Trigger
     * Created 2018/11/19 16:40
     */
    @Slf4j
    @Component
    public class DynamicTask implements SchedulingConfigurer {
        @Autowired
        private RedisServer redisServer;
        private static String cron;
    
        @Override
        public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) {
            scheduledTaskRegistrar.addTriggerTask(doTask(), getTrigger());
        }
    
        private Runnable doTask(){
            return new Runnable() {
                @Override
                public void run() {
                    log.info("**** mytask first to run: {}",new Date(System.currentTimeMillis()));
                }
            };
        }
    
        private Trigger getTrigger(){
            return new Trigger() {
                @Override
                public Date nextExecutionTime(TriggerContext triggerContext) {
                    CronTrigger trigger = new CronTrigger(gerCron());
                    return trigger.nextExecutionTime(triggerContext);
                }
            };
        }
    
        public String gerCron(){
            String newCron = redisServer.get("crontime");
            log.info("*** get time: {} ",newCron);
            if(StringUtils.isEmpty(newCron)){
                log.info(" get cron time fail");
            }else if(!newCron.equals(cron)){
                log.info("newCrontime: {} <-> oldCrontime: {}", newCron, cron);
                cron = newCron;
            }
    
            return  cron;
        }
    
    
    }