springboot定时器

注解使用

定时任务使用。

先在springboot入口类添加注释： EnableScheduling

@SpringBootApplication
@EnableScheduling
public class GirlApplication {
    public static void main(String[] args) {
        SpringApplication.run(GirlApplication.class, args);
    }
}

再在定时类上添加注解，感谢网友提供的可视化Cron表达式生成器

@Component
public class printScheduler {
    private final Logger logger = LoggerFactory.getLogger(this.getClass());
    @Scheduled(cron="0/5 * * * * ?")
    public void scheduleCheck() {
        logger.info("每5秒执行一次");
    }
}

自定义使用

参考：https://www.jianshu.com/p/deede3837293

package com.jege.spring.boot.task;
import java.text.SimpleDateFormat;
import java.util.Date;
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 com.jege.spring.boot.data.jpa.entity.User;
import com.jege.spring.boot.data.jpa.repository.UserRepository;
/**
 * @author JE哥
 * @email 1272434821@qq.com
 * @description:动态修改定时任务cron参数
 */
@Component
public class DynamicScheduledTask implements SchedulingConfigurer {
  private static final SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
  private static final String DEFAULT_CRON = "0/5 * * * * ?";
  private String cron = DEFAULT_CRON;
  @Autowired
  private UserRepository userRepository;
  @Override
  public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {
    taskRegistrar.addTriggerTask(new Runnable() {
      @Override
      public void run() {
    if (!cron.equals(DEFAULT_CRON)) {
      User user = new User("je_ge", 20);
      userRepository.save(user);
    }
    // 定时任务的业务逻辑
    System.out.println("动态修改定时任务cron参数，当前时间：" + dateFormat.format(new Date()));
      }
    }, new Trigger() {
      @Override
      public Date nextExecutionTime(TriggerContext triggerContext) {
    // 定时任务触发，可修改定时任务的执行周期
    CronTrigger trigger = new CronTrigger(cron);
    Date nextExecDate = trigger.nextExecutionTime(triggerContext);
    return nextExecDate;
      }
    });
  }
  public void setCron(String cron) {
    this.cron = cron;
  }
}

启动类

@EnableScheduling

修改

@Autowired
DynamicScheduledTask dynamicScheduledTask;
// 更新动态任务时间
@RequestMapping("/updateDynamicScheduledTask")
@ResponseBody
public AjaxResult updateDynamicScheduledTask() {
  dynamicScheduledTask.setCron("0/10 * * * * ?");
  return new AjaxResult().success();
}