实践:SpringBoot实现定时任务的动态增删启停

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小Hub领读:

我以为动态停启定时任务一般用quartz,没想到还可以通过ScheduledTaskRegistrar来拓展。但是分布式场景,建议还是用quartz吧!

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。

定时任务列表页

定时任务执行日志

添加执行定时任务的线程池配置类

搜索公纵号:MarkerHub,关注回复[ vue ]获取前后端入门教程! @Configuration public class SchedulingConfig { @Bean public TaskScheduler taskScheduler() { ThreadPoolTaskScheduler taskScheduler = new ThreadPoolTaskScheduler();

    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 class ScheduledTask {

volatile ScheduledFuture<?> future;


public void cancel() {
    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。

public class SchedulingRunnable implements Runnable {

private static final Logger logger = LoggerFactory.getLogger(SchedulingRunnable.class);

private String beanName;

private String methodName;

private String params;

public SchedulingRunnable(String beanName, String methodName) {
    this(beanName, methodName, null);
}

public SchedulingRunnable(String beanName, String methodName, String params) {
    this.beanName = beanName;
    this.methodName = methodName;
    this.params = params;
}

@Override
public void run() {
    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) return true;
    if (o == null || getClass() != o.getClass()) return false;
    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
public int hashCode() {
    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。

@Component public class CronTaskRegistrar implements DisposableBean {

private final Map<Runnable, ScheduledTask> scheduledTasks = new ConcurrentHashMap<>(16);

@Autowired
private TaskScheduler taskScheduler;

public TaskScheduler getScheduler() {
    return this.taskScheduler;
}

public void addCronTask(Runnable task, String cronExpression) {
    addCronTask(new CronTask(task, cronExpression));
}

public void addCronTask(CronTask cronTask) {
    if (cronTask != null) {
        Runnable task = cronTask.getRunnable();
        if (this.scheduledTasks.containsKey(task)) {
            removeCronTask(task);
        }

        this.scheduledTasks.put(task, scheduleCronTask(cronTask));
    }
}

public void removeCronTask(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;
}


@Override
public void destroy() {
    for (ScheduledTask task : this.scheduledTasks.values()) {
        task.cancel();
    }

    this.scheduledTasks.clear();
}

} 添加定时任务示例类

@Component("demoTask") public class DemoTask { public void taskWithParams(String params) { System.out.println("执行有参示例任务:" + params); }

public void taskNoParams() {
    System.out.println("执行无参示例任务");
}

} 定时任务数据库表设计

定时任务数据库表设计

添加定时任务实体类

public class SysJobPO {

private Integer jobId;

private String beanName;

private String methodName;

private String methodParams;

private String cronExpression;

private Integer jobStatus;

private String remark;

private Date createTime;

private Date updateTime;

public Integer getJobId() {
    return jobId;
}

public void setJobId(Integer jobId) {
    this.jobId = jobId;
}

public String getBeanName() {
    return beanName;
}

public void setBeanName(String beanName) {
    this.beanName = beanName;
}

public String getMethodName() {
    return methodName;
}

public void setMethodName(String methodName) {
    this.methodName = methodName;
}

public String getMethodParams() {
    return methodParams;
}

public void setMethodParams(String methodParams) {
    this.methodParams = methodParams;
}

public String getCronExpression() {
    return cronExpression;
}

public void setCronExpression(String cronExpression) {
    this.cronExpression = cronExpression;
}

public Integer getJobStatus() {
    return jobStatus;
}

public void setJobStatus(Integer jobStatus) {
    this.jobStatus = jobStatus;
}

public String getRemark() {
    return remark;
}

public void setRemark(String remark) {
    this.remark = remark;
}

public Date getCreateTime() {
    return createTime;
}

public void setCreateTime(Date createTime) {
    this.createTime = createTime;
}

public Date getUpdateTime() {
    return updateTime;
}

public void setUpdateTime(Date updateTime) {
    this.updateTime = updateTime;
}

} 新增定时任务

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 {

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。

@Service public class SysJobRunner implements CommandLineRunner {

private static final Logger logger = LoggerFactory.getLogger(SysJobRunner.class);

@Autowired
private ISysJobRepository sysJobRepository;

@Autowired
private CronTaskRegistrar cronTaskRegistrar;

@Override
public void run(String... args) {
    
    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

@Component public class SpringContextUtils implements ApplicationContextAware {

private static ApplicationContext applicationContext;

@Override
public void setApplicationContext(ApplicationContext applicationContext)
        throws BeansException {
    SpringContextUtils.applicationContext = applicationContext;
}

public static Object getBean(String name) {
    return applicationContext.getBean(name);
}

public static <T> T getBean(Class<T> requiredType) {
    return applicationContext.getBean(requiredType);
}

public static <T> T getBean(String name, Class<T> requiredType) {
    return applicationContext.getBean(name, requiredType);
}

public static boolean containsBean(String name) {
    return applicationContext.containsBean(name);
}

public static boolean isSingleton(String name) {
    return applicationContext.isSingleton(name);
}

public static Class<? extends Object> getType(String name) {
    return applicationContext.getType(name);
}

} --END--