spring boot 定时器

1、schedule 注解定时器

import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import java.util.Date;
/**
 * 注解 定时器
 *
 */
@Component
@Configuration
@EnableScheduling
public class FirstSecheduler {

    //五秒 运行一次
    @Scheduled(cron = "0/5 * * * * ?")
    public void fiveSeconds(){

        System.out.println("start:"+new Date().getSeconds());
        System.out.println("你好啊");
        System.out.println("end:"+new Date().getSeconds());
    }
}
2、动态定时器 可配置间隔时间 和内容

/**
 * 实现sechedule
 */
@Component
@Configuration
@EnableScheduling
public class SecondSchedule implements SchedulingConfigurer {


    @Override
    public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) {

        scheduledTaskRegistrar.addTriggerTask(() ->System.out.println("执行动态定时任务: " + new Date()),
                triggerContext -> {
                    //2.1 从数据库获取执行周期
                    String cron = "0/5 * * * * ?";
                    //2.3 返回执行周期(Date)
                    return new CronTrigger(cron).nextExecutionTime(triggerContext);
                }

        );
    }
}
3、使用多线程定时器

import org.springframework.scheduling.annotation.Async;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import java.util.Date;
/**
 * 多线程定时任务
 */

@Component
@EnableScheduling //开启定时器
@EnableAsync //开启多线程
public class ThreeSChedule {

    @Async
    @Scheduled(fixedDelay = 1000)
    public void first(){

        System.out.println("first:"+new Date().toLocaleString());
    }

    @Async
    @Scheduled(fixedDelay = 1000)
    public void second(){

        System.out.println("second:"+new Date().toLocaleString());
    }

}
4、使用外部 quartz定时
pom配置

<dependency>
    <groupId>org.quartz-scheduler</groupId>
    <artifactId>quartz</artifactId>
    <version>2.3.1</version>
</dependency>

import java.util.Date;
/**
 * 定义任务类 实现 Job 接口
 */
public class FirstQuartz implements Job {
    @Override
    public void execute(JobExecutionContext jobExecutionContext) throws JobExecutionException {

        System.out.println("quartz"+new Date().toLocaleString());

    }
}

import org.quartz.*;
import org.quartz.impl.StdSchedulerFactory;

/**
 * 主函数调用quartz
 */
public class QuartzMain {

    public static void main(String[] args) throws Exception{

        //创建job对象
        JobDetail jobDetail = JobBuilder.newJob(FirstQuartz.class).build();

        //触发时间
        Trigger trigger = TriggerBuilder.newTrigger().withSchedule(
                CronScheduleBuilder.cronSchedule("0/2 * * * * ?")).build();

        //作业内容
        Scheduler scheduler = StdSchedulerFactory.getDefaultScheduler();
        scheduler.scheduleJob(jobDetail,trigger);
        //启动
        scheduler.start();



    }
}

可根据不同需求使用

以上是自学总结。有借鉴前辈帖子望见谅。不足之处请多多指教