springcloud-定時任務

1.定時時間固定，只能在后台代碼更改

@Configuration
@EnableScheduling public class ScheduleTask {
    @Autowired     private UploadServiceImpl uploadServiceImpl;

    //添加定時任務,寫死時間
    @Scheduled(cron = "0 */1 * * * ?") private void configureTasks() {
        uploadServiceImpl.putLocalFile(); //任務內容
    }
}

2.在數據庫獲取定時時間

　　2.1 建表

DROP TABLE IF EXISTS `cron`;
CREATE TABLE `cron`  (
  `cron_id` varchar(30) NOT NULL PRIMARY KEY,
  `cron` varchar(30) NOT NULL  
);
INSERT INTO `cron` VALUES ('1', '0/5 * * * * ?');

       select cron from cron limit 1;

　　2.2  后台代碼

@Configuration
@EnableScheduling
public class ScheduleTask implements SchedulingConfigurer {
    //獲取數據庫定時時間
    @Autowired     private UploadServiceImpl uploadServiceImpl; 

    //添加定時任務,寫死時間
    @Scheduled(cron = "0 */1 * * * ?") private void configureTasks() { uploadServiceImpl.putLocalFile(); //任務內容
 } //添加定時任務,數據庫可修改時間格式
    @Override
    public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) {

        scheduledTaskRegistrar.addTriggerTask(
                //1.添加任務內容(Runnable)
                () -> uploadServiceImpl.putLocalFile(),
                //2.設置執行周期(Trigger)
                triggerContext -> {
                    //2.1 從數據庫獲取執行周期
                    String cron = uploadServiceImpl.getCron();
                    //2.2 合法性校驗.
                    if (StringUtils.isEmpty(cron)) {
                       throw new RuntimeException("定時格式錯誤");
                    }
                    //2.3 返回執行周期(Date)
                    return new CronTrigger(cron).nextExecutionTime(triggerContext);
                }
        );
    }


    }