• Springboot定时任务热部署设计及实现

    1. 需求来源

    业务上需要将定时器的执行周期进行配置（新增、编辑、删除），并支持热部署（直接生效，无需重启）

    2. 设计

    2.1 表结构(postgresql)

    1. drop table if exists t_scheduler;
    2. create table t_scheduler (
    3.     id int4 not null,
    4.     task_name varchar(32) not null,
    5.     cron varchar(32) not null,
    6.     delete int2 not null default 0,
    7.     constraint t_scheduler_pkey primary key ("id")
    8. );
    9. comment on column t_scheduler.id is '任务Id';
    10. comment on column t_scheduler.task_name is '任务名称';
    11. comment on column t_scheduler.cron is '任务执行周期';
    12. comment on column t_scheduler.delete is '任务是否删除0未删除1已删除';
    13.  
    1. -- 任务数据
    2. insert into t_scheduler values(1, 'SyncUser', '0/10 * * * * ?', 0);
    3. insert into t_scheduler values(2, 'WeatherTask', '0/10 * * * * ?', 0);

    2.2 程序设计

    主配置类

    里面包含一个定时任务，扫描上述任务配置表，检查有没有更新

    任务接口（该接口继承Runnable）

    任务定义接口，自定义的任务，均实现该接口

    任务对象工厂

    用来通过配置的任务名，反射获取任务对象

    任务Dao

    包含任务查询等

    3. 代码

    3.1 主配置类

    1. package com.hz.basepro.schedule.start;
    2.  
    3. import com.hz.basepro.bean.ScheduleTask;
    4. import com.hz.basepro.schedule.dao.businessmapper.ScheduleMapper;
    5. import com.hz.basepro.schedule.task.TaskHelper;
    6. import org.slf4j.Logger;
    7. import org.slf4j.LoggerFactory;
    8. import org.springframework.beans.factory.annotation.Autowired;
    9. import org.springframework.scheduling.annotation.EnableScheduling;
    10. import org.springframework.scheduling.annotation.Scheduled;
    11. import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
    12. import org.springframework.scheduling.support.CronTrigger;
    13. import org.springframework.stereotype.Component;
    14.  
    15. import java.util.HashMap;
    16. import java.util.Iterator;
    17. import java.util.List;
    18. import java.util.Map;
    19. import java.util.stream.Collectors;
    20.  
    21. @Component
    22. @EnableScheduling
    23. public class ScheduleTaskConfig {
    24.  
    25.     private static final Logger LOGGER = LoggerFactory.getLogger(ScheduleTaskConfig.class);
    26.  
    27.     @Autowired
    28.     private ScheduleMapper scheduleMapper;
    29.  
    30.     /**
    31.      * 任务Map
    32.      *
    33.      */
    34.     private Map<Integer, ScheduleTask> taskMap = new HashMap<>();
    35.  
    36.     /**
    37.      * 任务对应的定时器Map
    38.      */
    39.     private Map<Integer, ThreadPoolTaskScheduler> schedulerMap = new HashMap<>();
    40.  
    41.     @Scheduled(initialDelay = 0, fixedRate = 1 * 1000)
    42.     public void checkTask() {
    43.  
    44.         List<ScheduleTask> scheduleTaskList = scheduleMapper.getAllScheduleTask();
    45.         for (ScheduleTask scheduleTask : scheduleTaskList) {
    46.             if (taskMap.containsKey(scheduleTask.getId())) {
    47.                 ScheduleTask oldTask = taskMap.get(scheduleTask.getId());
    48.  
    49.                 // cron发生改变 1. 移除现有的任务 2. 重新生成新的任务
    50.                 if (!scheduleTask.getCron().equals(oldTask.getCron())) {
    51.  
    52.                     removeTask(oldTask.getId());
    53.                     addTask(scheduleTask);
    54.  
    55.                 }
    56.                 taskMap.remove(scheduleTask.getId());
    57.             } else {
    58.                 // cron未改变，添加新任务
    59.                 addTask(scheduleTask);
    60.             }
    61.  
    62.             taskMap.put(scheduleTask.getId(), scheduleTask);
    63.         }
    64.  
    65.         // 移除已经删除的任务
    66.         List<Integer> taskIds = scheduleTaskList.stream().map(task -> task.getId()).collect(Collectors.toList());
    67.         for(Iterator<Map.Entry<Integer, ScheduleTask>> it = taskMap.entrySet().iterator();it.hasNext();) {
    68.             Map.Entry<Integer, ScheduleTask> entry = it.next();
    69.             Integer oldTaskId = entry.getKey();
    70.             if (!taskIds.contains(oldTaskId)) {
    71.                 // 1. 移除任务
    72.                 removeTask(oldTaskId);
    73.                 // 2. map移除任务
    74.                 it.remove();
    75.             }
    76.         }
    77.     }
    78.  
    79.  
    80.     /**
    81.      * 添加定时任务
    82.      *
    83.      * @param task
    84.      */
    85.     public void addTask(ScheduleTask task) {
    86.         ThreadPoolTaskScheduler scheduler = new ThreadPoolTaskScheduler();
    87.  
    88.         scheduler.setThreadNamePrefix(task.getTaskName());
    89.         scheduler.setPoolSize(1);
    90.         scheduler.initialize();
    91.         scheduler.schedule(TaskHelper.getTask(task.getTaskName()), new CronTrigger(task.getCron()));
    92.  
    93.         schedulerMap.put(task.getId(), scheduler);
    94.  
    95.         LOGGER.info("定时器创建：{}.", task.getId());
    96.     }
    97.  
    98.     /**
    99.      * 移除定时任务
    100.      *
    101.      * @param taskId
    102.      */
    103.     public void removeTask(Integer taskId) {
    104.         try {
    105.             ThreadPoolTaskScheduler scheduler = schedulerMap.get(taskId);
    106.             if (scheduler == null) {
    107.                 LOGGER.info("定时器不存在：{}.", taskId);
    108.             } else {
    109.                 try {
    110.                     scheduler.shutdown();
    111.                 } catch (Exception e) {
    112.                     LOGGER.error("线程池关闭失败, taskId: {}.", taskId, e);
    113.  
    114.                     try {
    115.                         scheduler.shutdown();
    116.                     } catch (Exception ex) {
    117.                         LOGGER.error("线程池再次关闭失败, taskId: {}.", taskId, e);
    118.                     }
    119.                 }
    120.             }
    121.         } finally {
    122.             schedulerMap.remove(taskId);
    123.         }
    124.  
    125.         LOGGER.info("定时器销毁：{}.", taskId);
    126.     }
    127. }

    3.2 任务对象工厂TaskHelper

    1. package com.hz.basepro.schedule.task;
    2.  
    3. import com.hz.basepro.bean.CommonException;
    4. import org.slf4j.Logger;
    5. import org.slf4j.LoggerFactory;
    6.  
    7. public class TaskHelper {
    8.  
    9.     private static final Logger LOGGER = LoggerFactory.getLogger(TaskHelper.class);
    10.     private static final String basePackage = "com.hz.basepro.schedule.task.impl.";
    11.  
    12.     public static Task getTask(String taskName) {
    13.         try {
    14.             Class<?> clazz = Class.forName(basePackage + taskName);
    15.             Task task = (Task)clazz.newInstance();
    16.             return task;
    17.         } catch (Exception e) {
    18.             throw new CommonException("找不到对应的任务:" + taskName,  e);
    19.         }
    20.     }
    21.  
    22. }

    3.3 任务对象

    1. package com.hz.basepro.schedule.task;
    2.  
    3. public interface Task extends Runnable {
    4. }
    1. package com.hz.basepro.schedule.task.impl;
    2.  
    3. import com.hz.basepro.schedule.task.Task;
    4. import org.slf4j.Logger;
    5. import org.slf4j.LoggerFactory;
    6.  
    7. import java.text.SimpleDateFormat;
    8. import java.util.Date;
    9.  
    10. public class SyncUser implements Task {
    11.  
    12.     private static final Logger LOGGER = LoggerFactory.getLogger(SyncUser.class);
    13.  
    14.     private static final ThreadLocal<SimpleDateFormat> FORMAT_LOCAL = ThreadLocal.withInitial(() -> new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
    15.  
    16.  
    17.     @Override
    18.     public void run() {
    19.         SimpleDateFormat sdf = FORMAT_LOCAL.get();
    20.         LOGGER.info("同步用户任务进行中：{}", sdf.format(new Date()));
    21.     }
    22. }
    1. package com.hz.basepro.schedule.task.impl;
    2.  
    3. import com.hz.basepro.schedule.task.Task;
    4. import org.slf4j.Logger;
    5. import org.slf4j.LoggerFactory;
    6.  
    7. import java.text.SimpleDateFormat;
    8. import java.util.Date;
    9.  
    10. public class WeatherTask implements Task {
    11.  
    12.     private static final Logger LOGGER = LoggerFactory.getLogger(WeatherTask.class);
    13.  
    14.     private static final ThreadLocal<SimpleDateFormat> FORMAT_LOCAL = ThreadLocal.withInitial(() -> new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
    15.  
    16.     @Override
    17.     public void run() {
    18.         SimpleDateFormat sdf = FORMAT_LOCAL.get();
    19.         LOGGER.info("天气任务进行中：{}", sdf.format(new Date()));
    20.     }
    21. }

    3.4 ScheduleMapper

    1. package com.hz.basepro.schedule.dao.businessmapper;
    2.  
    3. import com.hz.basepro.bean.ScheduleTask;
    4.  
    5. import java.util.List;
    6.  
    7. public interface ScheduleMapper {
    8.  
    9.     /**
    10.      * 获取所有任务
    11.      *
    12.      * @return
    13.      */
    14.     List<ScheduleTask> getAllScheduleTask();
    15.  
    16. }

    3.5 查询sql

    1. <select id="getAllScheduleTask" resultType="com.hz.basepro.bean.ScheduleTask">
    2.      select id, task_name, cron from t_scheduler where delete = 0
    3. </select>

    3.6涉及的Bean

    1. package com.hz.basepro.bean;
    2.  
    3. public class ScheduleTask {
    4.  
    5.     private int id;
    6.  
    7.     private String taskName;
    8.  
    9.     private String cron;
    10.  
    11.     public int getId() {
    12.         return id;
    13.     }
    14.  
    15.     public void setId(int id) {
    16.         this.id = id;
    17.     }
    18.  
    19.     public String getTaskName() {
    20.         return taskName;
    21.     }
    22.  
    23.     public void setTaskName(String taskName) {
    24.         this.taskName = taskName;
    25.     }
    26.  
    27.     public String getCron() {
    28.         return cron;
    29.     }
    30.  
    31.     public void setCron(String cron) {
    32.         this.cron = cron;
    33.     }
    34.  
    35.     @Override
    36.     public String toString() {
    37.         return "SchedulerTask{" +
    38.                 "id=" + id +
    39.                 ", taskName='" + taskName + '\'' +
    40.                 ", cron='" + cron + '\'' +
    41.                 '}';
    42.     }
    43. }

    4. 执行结果

    4.1 初始执行结果

    1. 2022-06-29 14:54:23,281 INFO [scheduling-1] (ScheduleTaskConfig.java:99)- 定时器创建：2.
    2. 2022-06-29 14:54:23,283 INFO [scheduling-1] (ScheduleTaskConfig.java:99)- 定时器创建：1.
    3. 2022-06-29 14:54:30,001 INFO [WeatherTask1] (WeatherTask.java:19)- 天气任务进行中：2022-06-29 14:54:30
    4. 2022-06-29 14:54:30,001 INFO [SyncUser1] (SyncUser.java:20)- 同步用户任务进行中：2022-06-29 14:54:30
    5. 2022-06-29 14:54:40,000 INFO [SyncUser1] (SyncUser.java:20)- 同步用户任务进行中：2022-06-29 14:54:40
    6. 2022-06-29 14:54:40,000 INFO [WeatherTask1] (WeatherTask.java:19)- 天气任务进行中：2022-06-29 14:54:40
    7. 2022-06-29 14:54:50,001 INFO [SyncUser1] (SyncUser.java:20)- 同步用户任务进行中：2022-06-29 14:54:50

    4.2 修改任务执行周期

    update t_scheduler set cron = '0/5 * * * * ?' where id = 1;

    4.3 修改后的执行日志

    1. 2022-06-29 14:56:22,629 INFO [scheduling-1] (ScheduleTaskConfig.java:125)- 定时器销毁：1.
    2. 2022-06-29 14:56:22,631 INFO [scheduling-1] (ScheduleTaskConfig.java:99)- 定时器创建：1.
    3. 2022-06-29 14:56:25,001 INFO [SyncUser1] (SyncUser.java:20)- 同步用户任务进行中：2022-06-29 14:56:25
    4. 2022-06-29 14:56:30,000 INFO [WeatherTask1] (WeatherTask.java:19)- 天气任务进行中：2022-06-29 14:56:30
    5. 2022-06-29 14:56:30,000 INFO [SyncUser1] (SyncUser.java:20)- 同步用户任务进行中：2022-06-29 14:56:30
    6. 2022-06-29 14:56:35,001 INFO [SyncUser1] (SyncUser.java:20)- 同步用户任务进行中：2022-06-29 14:56:35
    7. 2022-06-29 14:56:40,001 INFO [SyncUser1] (SyncUser.java:20)- 同步用户任务进行中：2022-06-29 14:56:40
    8. 2022-06-29 14:56:40,001 INFO [WeatherTask1] (WeatherTask.java:19)- 天气任务进行中：2022-06-29 14:56:40

    4.4 结论

           符合期望结果，修改的周期的任务按照期望5s执行一次。未修改的任务仍然是10s执行一次。

  • 相关阅读:
    信息安全服务CCRC认证申报的完整流程
    【AXI4 verilog】手把手带你撸AXI代码（四、AXI4接口的RAM设计）
    uniapp 常见的问题以及解决办法
    Spring IOC源码：registerBeanPostProcessors 详解
    《数据结构、算法与应用C++语言描述》-栈的应用-开关盒布线问题
    Oracle/PLSQL: Least Function
    JavaScript中事件及其详解
    shiro会话管理
    一个快速切换一个底层实现的思路分享
    数组的存储和压缩
  • 原文地址：https://blog.csdn.net/pp_lan/article/details/125521213