有关定时任务的使用

<!--引入quartz定时框架-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-quartz</artifactId>
    </dependency>

(1) spring中使用两个注解 实现定时任务的实现

（1）在启动类开启定时任务@EnableScheduling
@SpringBootApplication
//开启定时任务
@EnableScheduling
public class Application{ 
    public static void main(String[] args) { 
       		SpringApplication.run(Application.class, args);
    }
}
（2）@Scheduled(cron = " ")来指定自动执行规则

    /** * 每分钟执行一次 */
    @Scheduled(cron = "0 0/1 * * * ?")
    public void init() { 
        log.info("定时任务执行开始");
       //业务方法逻辑...
        log.info("定时任务执行结束");
    }

（2）有关quartz实现定时任务

public class MyJob implements Job { 
    @Override
    public void execute(JobExecutionContext jobExecutionContext) throws JobExecutionException { 
        SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String format = sdf.format(new Date());
        System.out.println("当前时间-format:time="+format);
    }
}


public class MyScheduler { 
    public static void getMyScheduler() throws SchedulerException { 
        //创建schedule 调度器
        Scheduler scheduler = StdSchedulerFactory.getDefaultScheduler();

        //创建jobbuilder
        JobDetail jobDetail = (JobDetail) JobBuilder.newJob(MyJob.class)
                .withIdentity("nala","jobDetailGroup")
                .withDescription("使用Cron")
                .build();
        //创建TriggerBuilder 触发器 设置触发时间 3天一次
        CronTrigger trigger = TriggerBuilder.newTrigger()
                .withIdentity("nala", "tiggerGroup")
                .withDescription("使用cron设置调度时间")
                .withSchedule(CronScheduleBuilder.cronSchedule("0 0 0 */3 * ? "))
                .build();

        //关联
        scheduler.scheduleJob(jobDetail,trigger);

        if(!scheduler.isShutdown()){ 
            scheduler.start();
        }
        //执行
        scheduler.start();

        //一直不关闭schedule 就会一直运行
        while (true){ 
        }
    }

    @Test
    public  void test() throws SchedulerException { 
        getMyScheduler();
    }
}

(3) Spring Boot集成Quartz实现定时任务

//创建自定义job
public class MyJob extends QuartzJobBean { 
    @Override
    protected void executeInternal(JobExecutionContext jobExecutionContext) throws JobExecutionException { 
        SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String format = sdf.format(new Date());
        System.out.println("jobExecutionContext"+format);
    }
}



/** * @Date 2021/10/22 14:36 */
@Configuration
@DisallowConcurrentExecution
public class QuartzConfig { 

    @Bean
    public JobDetail getJobDetail() { 
        return JobBuilder.newJob(MyJob.class)
                .withIdentity("jobDetail","jobDetailGroup")
                .withDescription("使用cron")
                .storeDurably()
                .build();
    }

    @Bean
    public Trigger getTrigger() { 
        //cron方式，每隔3天执行一次
        return TriggerBuilder.newTrigger().forJob(getJobDetail())
                .withIdentity("trigger","triggerGroup")
                .withDescription("使用Cron表达式")
                .withSchedule(CronScheduleBuilder.cronSchedule("0 0 0 */3 * ?"))
                .build();
    }
}