超级赞！SpringBoot一键搞定动态增删启停定时任务~

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来源：www.jianshu.com/p/0f68936393fd

在spring boot项目中，可以通过@EnableScheduling注解和@Scheduled注解实现定时任务，也可以通过SchedulingConfigurer接口来实现定时任务。但是这两种方式不能动态添加、删除、启动、停止任务。

要实现动态增删启停定时任务功能，比较广泛的做法是集成Quartz框架。但是本人的开发原则是：在满足项目需求的情况下，尽量少的依赖其它框架，避免项目过于臃肿和复杂。

查看spring-context这个jar包中org.springframework.scheduling.ScheduledTaskRegistrar这个类的源代码，发现可以通过改造这个类就能实现动态增删启停定时任务功能。

添加执行定时任务的线程池配置类

@ConfigurationpublicclassSchedulingConfig{ @Beanpublic TaskScheduler taskScheduler(){ ThreadPoolTaskScheduler taskScheduler = new ThreadPoolTaskScheduler(); // 定时任务执行线程池核心线程数 taskScheduler.setPoolSize(4); taskScheduler.setRemoveOnCancelPolicy(true); taskScheduler.setThreadNamePrefix("TaskSchedulerThreadPool-"); return taskScheduler; } }

添加ScheduledFuture的包装类。ScheduledFuture是ScheduledExecutorService定时任务线程池的执行结果。

public final classScheduledTask { volatile ScheduledFuture<?> future; /** * 取消定时任务 */publicvoidcancel() { ScheduledFuture<?> future = this.future; if (future != null) { future.cancel(true); } } }

添加Runnable接口实现类，被定时任务线程池调用，用来执行指定bean里面的方法。

publicclassSchedulingRunnableimplementsRunnable { privatestatic final Logger logger = LoggerFactory.getLogger(SchedulingRunnable.class); private String beanName; private String methodName; private String params; publicSchedulingRunnable(String beanName, String methodName) { this(beanName, methodName, null); } publicSchedulingRunnable(String beanName, String methodName, String params) { this.beanName = beanName; this.methodName = methodName; this.params = params; } @Override publicvoidrun() { logger.info("定时任务开始执行 - bean：{}，方法：{}，参数：{}", beanName, methodName, params); long startTime = System.currentTimeMillis(); try { Object target = SpringContextUtils.getBean(beanName); Method method = null; if (StringUtils.isNotEmpty(params)) { method = target.getClass().getDeclaredMethod(methodName, String.class); } else { method = target.getClass().getDeclaredMethod(methodName); } ReflectionUtils.makeAccessible(method); if (StringUtils.isNotEmpty(params)) { method.invoke(target, params); } else { method.invoke(target); } } catch (Exception ex) {

 logger.error(String.format("定时任务执行异常 - bean：%s，方法：%s，参数：%s ", beanName, methodName, params), ex);

} long times = System.currentTimeMillis() - startTime;

 logger.info("定时任务执行结束 - bean：{}，方法：{}，参数：{}，耗时：{} 毫秒", beanName, methodName, params, times);

} @Override public boolean equals(Object o) { if (this == o) returntrue; if (o == null || getClass() != o.getClass()) returnfalse; SchedulingRunnable that = (SchedulingRunnable) o; if (params == null) { return beanName.equals(that.beanName) && methodName.equals(that.methodName) && that.params == null; } return beanName.equals(that.beanName) && methodName.equals(that.methodName) && params.equals(that.params); } @Override publicinthashCode() { if (params == null) { return Objects.hash(beanName, methodName); } return Objects.hash(beanName, methodName, params); } }

添加定时任务注册类，用来增加、删除定时任务。

@ComponentpublicclassCronTaskRegistrarimplementsDisposableBean{ privatefinal Map<Runnable, ScheduledTask> scheduledTasks = new ConcurrentHashMap<>(16); @Autowiredprivate TaskScheduler taskScheduler; public TaskScheduler getScheduler(){ returnthis.taskScheduler; } publicvoidaddCronTask(Runnable task, String cronExpression){ addCronTask(new CronTask(task, cronExpression)); } publicvoidaddCronTask(CronTask cronTask){ if (cronTask != null) { Runnable task = cronTask.getRunnable(); if (this.scheduledTasks.containsKey(task)) { removeCronTask(task); } this.scheduledTasks.put(task, scheduleCronTask(cronTask)); } } publicvoidremoveCronTask(Runnable task){ ScheduledTask scheduledTask = this.scheduledTasks.remove(task); if (scheduledTask != null) scheduledTask.cancel(); } public ScheduledTask scheduleCronTask(CronTask cronTask){ ScheduledTask scheduledTask = new ScheduledTask(); scheduledTask.future = this.taskScheduler.schedule(cronTask.getRunnable(), cronTask.getTrigger()); return scheduledTask; } @Overridepublicvoiddestroy(){ for (ScheduledTask task : this.scheduledTasks.values()) { task.cancel(); } this.scheduledTasks.clear(); } }

添加定时任务示例类

@Component("demoTask") publicclassDemoTask { publicvoidtaskWithParams(String params) { System.out.println("执行有参示例任务：" + params); } publicvoidtaskNoParams() { System.out.println("执行无参示例任务"); } }

定时任务数据库表设计

添加定时任务实体类

publicclass SysJobPO { /** * 任务ID */private Integer jobId; /** * bean名称 */privateString beanName; /** * 方法名称 */privateString methodName; /** * 方法参数 */privateString methodParams; /** * cron表达式 */privateString cronExpression; /** * 状态（1正常 0暂停） */private Integer jobStatus; /** * 备注 */privateString remark; /** * 创建时间 */privateDate createTime; /** * 更新时间 */privateDate updateTime; public Integer getJobId() { return jobId; } publicvoid setJobId(Integer jobId) { this.jobId = jobId; } publicString getBeanName() { return beanName; } publicvoid setBeanName(String beanName) { this.beanName = beanName; } publicString getMethodName() { return methodName; } publicvoid setMethodName(String methodName) { this.methodName = methodName; } publicString getMethodParams() { return methodParams; } publicvoid setMethodParams(String methodParams) { this.methodParams = methodParams; } publicString getCronExpression() { return cronExpression; } publicvoid setCronExpression(String cronExpression) { this.cronExpression = cronExpression; } public Integer getJobStatus() { return jobStatus; } publicvoid setJobStatus(Integer jobStatus) { this.jobStatus = jobStatus; } publicString getRemark() { return remark; } publicvoid setRemark(String remark) { this.remark = remark; } publicDate getCreateTime() { return createTime; } publicvoid setCreateTime(Date createTime) { this.createTime = createTime; } publicDate getUpdateTime() { return updateTime; } publicvoid setUpdateTime(Date updateTime) { this.updateTime = updateTime; } }

新增定时任务

boolean success = sysJobRepository.addSysJob(sysJob); if (!success) return OperationResUtils.fail("新增失败"); else { if (sysJob.getJobStatus().equals(SysJobStatus.NORMAL.ordinal())) {

 SchedulingRunnable task = new SchedulingRunnable(sysJob.getBeanName(), sysJob.getMethodName(), sysJob.getMethodParams());

cronTaskRegistrar.addCronTask(task, sysJob.getCronExpression()); } } return OperationResUtils.success();

修改定时任务，先移除原来的任务，再启动新任务

boolean success = sysJobRepository.editSysJob(sysJob); if (!success) return OperationResUtils.fail("编辑失败"); else { //先移除再添加 if (existedSysJob.getJobStatus().equals(SysJobStatus.NORMAL.ordinal())) {

 SchedulingRunnable task = new SchedulingRunnable(existedSysJob.getBeanName(), existedSysJob.getMethodName(), existedSysJob.getMethodParams());

cronTaskRegistrar.removeCronTask(task); } if (sysJob.getJobStatus().equals(SysJobStatus.NORMAL.ordinal())) {

 SchedulingRunnable task = new SchedulingRunnable(sysJob.getBeanName(), sysJob.getMethodName(), sysJob.getMethodParams());

cronTaskRegistrar.addCronTask(task, sysJob.getCronExpression()); } } return OperationResUtils.success();

删除定时任务

boolean success = sysJobRepository.deleteSysJobById(req.getJobId()); if (!success) return OperationResUtils.fail("删除失败"); else{ if (existedSysJob.getJobStatus().equals(SysJobStatus.NORMAL.ordinal())) {

 SchedulingRunnable task = new SchedulingRunnable(existedSysJob.getBeanName(), existedSysJob.getMethodName(), existedSysJob.getMethodParams());

cronTaskRegistrar.removeCronTask(task); } } return OperationResUtils.success();

定时任务启动/停止状态切换

if (existedSysJob.getJobStatus().equals(SysJobStatus.NORMAL.ordinal())) {

 SchedulingRunnable task = new SchedulingRunnable(existedSysJob.getBeanName(), existedSysJob.getMethodName(), existedSysJob.getMethodParams());

cronTaskRegistrar.addCronTask(task, existedSysJob.getCronExpression()); } else {

 SchedulingRunnable task = new SchedulingRunnable(existedSysJob.getBeanName(), existedSysJob.getMethodName(), existedSysJob.getMethodParams());

cronTaskRegistrar.removeCronTask(task); }

添加实现了CommandLineRunner接口的SysJobRunner类，当spring boot项目启动完成后，加载数据库里状态为正常的定时任务。

@ServicepublicclassSysJobRunnerimplementsCommandLineRunner{ privatestaticfinal Logger logger = LoggerFactory.getLogger(SysJobRunner.class); @Autowiredprivate ISysJobRepository sysJobRepository; @Autowiredprivate CronTaskRegistrar cronTaskRegistrar; @Overridepublicvoidrun(String... args){ // 初始加载数据库里状态为正常的定时任务 List<SysJobPO> jobList = sysJobRepository.getSysJobListByStatus(SysJobStatus.NORMAL.ordinal()); if (CollectionUtils.isNotEmpty(jobList)) { for (SysJobPO job : jobList) { SchedulingRunnable task = new SchedulingRunnable(job.getBeanName(), job.getMethodName(), job.getMethodParams()); cronTaskRegistrar.addCronTask(task, job.getCronExpression()); } logger.info("定时任务已加载完毕..."); } } }

工具类SpringContextUtils，用来从spring容器里获取bean

@ComponentpublicclassSpringContextUtilsimplementsApplicationContextAware{ privatestatic ApplicationContext applicationContext; @OverridepublicvoidsetApplicationContext(ApplicationContext applicationContext)throws BeansException { SpringContextUtils.applicationContext = applicationContext; } publicstatic Object getBean(String name){ return applicationContext.getBean(name); } publicstatic <T> T getBean(Class<T> requiredType){ return applicationContext.getBean(requiredType); } publicstatic <T> T getBean(String name, Class<T> requiredType){ return applicationContext.getBean(name, requiredType); } publicstaticbooleancontainsBean(String name){ return applicationContext.containsBean(name); } publicstaticbooleanisSingleton(String name){ return applicationContext.isSingleton(name); } publicstatic Class<? extends Object> getType(String name) { return applicationContext.getType(name); } }

本文完，参考本文代码可成功运行，亲测！

技术交流群

最后，D哥也建了一个技术群，主要探讨一些新的技术和开源项目值不值得去研究及IDEA使用的“骚操作”，有兴趣入群的同学，可长按扫描下方二维码，一定要备注：城市+昵称+技术方向，根据格式备注，可更快被通过且邀请进群。

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关键词

定时任务

SysJobStatus.NORMAL.ordinal

动态