基于Springboot的动态刷新定时任务

背景

对于一些不那么复杂的定时任务，好像也没必要上一整套xxl-job或者quartz之类的，自己简单实现一套也行

环境

• jdk 21
• Springboot 2.7.18
• nacos

目标

• 可以通过@EnableScheduling和比较简单的任务注册使用定时任务
• 定时任务的运行间隔可以通过nacos配置动态刷新
• 任务可以通过配置一键启停

代码

nacos配置

我这里把任务抽象出来单独配置在nacos:

scheduler:tasks:- name: test1cron: 0/5 * * * * ?desc: 测试1enabled: true- name: test2cron: 0/10 * * * * ?desc: 测试2enabled: false

Springboot配置

我这里是希望注入比较简单，如果你不喜欢也可以直接array注入，都一样的

@Component
@ConfigurationProperties(prefix = "scheduler")
public class SchedulerTasksNacosConfig extends ScheduleTasks {
}

@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
public class ScheduleTasks {private List<ScheduledTaskDto> tasks;@Data@Builder@AllArgsConstructor@NoArgsConstructorpublic static class ScheduledTaskDto {private String name;private String cron;private String desc;private boolean enabled;}
}

开始准备定时任务

接口

public interface SchedulerTaskService {/*** 获取任务ID** @return 任务ID*/String getTskId();/*** 获取任务** @return 任务*/Runnable getTask();
}

实际任务1

测试通过分布式锁确保一个时间点只有一个任务可执行

@Service
@Slf4j
public class Test1Task implements SchedulerTaskService {@Resourceprivate LockUtil lockUtil;@Overridepublic String getTskId() {return "test1";}@Overridepublic Runnable getTask() {return () -> {final String lockKey = getTskId();final String lockVal = lockUtil.tryLock(lockKey);if (StringUtils.isEmpty(lockVal)) {log.warn("任务-{} 尝试获取分布式锁失败，可能有其他实例正在执行该任务", getTskId());return; // 如果获取锁失败，直接返回}try {System.out.println("正常获得锁，执行测试1任务");} finally {lockUtil.unlock(lockKey, lockVal); // 确保在任务执行完毕后释放锁}};}

实际任务2

@Service
public class Test2Task implements SchedulerTaskService {@Overridepublic String getTskId() {return "test2";}@Overridepublic Runnable getTask() {return () -> System.out.println("任务2开始执行:" + new Date());}
}

注册并执行任务

import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.cloud.context.scope.refresh.RefreshScopeRefreshedEvent;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.event.EventListener;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import org.springframework.util.CollectionUtils;import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ScheduledFuture;
import java.util.stream.Collectors;@Configuration
@EnableScheduling
@RefreshScope
public class DynamicScheduleConfig {@Autowiredprivate SchedulerTasksNacosConfig schedulerTasksNacosConfig;@Autowiredprivate List<SchedulerTaskService> schedulerTaskServices;private ThreadPoolTaskScheduler scheduler;private final Map<String, ScheduledFuture<?>> futureMap = new HashMap<>();private final Map<String, Runnable> taskMap = new ConcurrentHashMap<>();/*** 类初始化，将所有定时任务都注册到Map中方便使用*/@PostConstructpublic void start() {if (!CollectionUtils.isEmpty(schedulerTaskServices)) {taskMap.putAll(schedulerTaskServices.stream().collect(Collectors.toMap(SchedulerTaskService::getTskId, SchedulerTaskService::getTask)));}scheduler = new ThreadPoolTaskScheduler();scheduler.initialize();scheduleAllTasks();}// 注册所有任务private void scheduleAllTasks() {List<ScheduleTasks.ScheduledTaskDto> tasks = schedulerTasksNacosConfig.getTasks();for (ScheduleTasks.ScheduledTaskDto taskDto : tasks) {// 跳过无效或关停的任务if (Objects.isNull(taskDto) || StringUtils.isEmpty(taskDto.getCron()) || StringUtils.isEmpty(taskDto.getName()) || !taskDto.isEnabled()) {continue; }scheduleTask(taskDto.getName(), taskDto.getCron(), taskMap.getOrDefault(taskDto.getName(), () -> System.out.println("没有找到对应任务")));}}private void scheduleTask(String taskName, String cron, Runnable task) {ScheduledFuture<?> future = scheduler.schedule(task,triggerContext -> new org.springframework.scheduling.support.CronTrigger(cron).nextExecutionTime(triggerContext));ScheduledFuture<?> oldFuture = futureMap.put(taskName, future);if (oldFuture != null) {oldFuture.cancel(false);}}@EventListener(RefreshScopeRefreshedEvent.class)public void onRefresh() {scheduleAllTasks();}// 类销毁前执行完最后的任务@PreDestroypublic void destroy() {for (ScheduledFuture<?> future : futureMap.values()) {if (future != null) {future.cancel(false);}}if (scheduler != null) {scheduler.shutdown();}}
}