2.6 定時任務(wù)管理實現(xiàn)類

@Slf4j
 @Service
 public class ScheduledTaskServiceImpl implements ScheduledTaskService {
 
     /**
      * 可重入鎖
      */
    private ReentrantLock lock = new ReentrantLock();
 
     /**
      * 定時任務(wù)線程池
      */
     @Autowired
     private ThreadPoolTaskScheduler threadPoolTaskScheduler;
 
     /**
      * 啟動狀態(tài)的定時任務(wù)集合
      */
     public Map<String, ScheduledFuture> scheduledFutureMap = new ConcurrentHashMap<>();
 
     @Autowired
     private ScheduledJobService scheduledJobService;
 
     @Override
     public Boolean start(ScheduledJob scheduledJob) {
         String jobKey = scheduledJob.getJobKey();
         log.info("啟動定時任務(wù)"+jobKey);
         //添加鎖放一個線程啟動，防止多人啟動多次
         lock.lock();
         log.info("加鎖完成");
 
         try {
             if(this.isStart(jobKey)){
                 log.info("當(dāng)前任務(wù)在啟動狀態(tài)中");
                 return false;
             }
             //任務(wù)啟動
             this.doStartTask(scheduledJob);
         } finally {
             lock.unlock();
             log.info("解鎖完畢");
         }
 
         return true;
     }
 
     /**
      * 任務(wù)是否已經(jīng)啟動
      */
     private Boolean isStart(String taskKey) {
         //校驗是否已經(jīng)啟動
         if (scheduledFutureMap.containsKey(taskKey)) {
             if (!scheduledFutureMap.get(taskKey).isCancelled()) {
                 return true;
             }
         }
         return false;
     }
 
     @Override
     public Boolean stop(String jobKey) {
         log.info("停止任務(wù) "+jobKey);
         boolean flag = scheduledFutureMap.containsKey(jobKey);
         log.info("當(dāng)前實例是否存在 "+flag);
         if(flag){
             ScheduledFuture scheduledFuture = scheduledFutureMap.get(jobKey);
 
             scheduledFuture.cancel(true);
 
             scheduledFutureMap.remove(jobKey);
         }
         return flag;
     }
 
     @Override
     public Boolean restart(ScheduledJob scheduledJob) {
         log.info("重啟定時任務(wù)"+scheduledJob.getJobKey());
         //停止
         this.stop(scheduledJob.getJobKey());
 
         return this.start(scheduledJob);
     }
 
     /**
      * 執(zhí)行啟動任務(wù)
      */
     public void doStartTask(ScheduledJob sj){
         log.info(sj.getJobKey());
         if(sj.getStatus().intValue() != 1)
             return;
         Class? clazz;
         ScheduledOfTask task;
         try {
             clazz = Class.forName(sj.getJobKey());
             task = (ScheduledOfTask) SpringContextUtil.getBean(clazz);
         } catch (ClassNotFoundException e) {
             throw new IllegalArgumentException("spring_scheduled_cron表數(shù)據(jù)" + sj.getJobKey() + "有誤", e);
         }
         Assert.isAssignable(ScheduledOfTask.class, task.getClass(), "定時任務(wù)類必須實現(xiàn)ScheduledOfTask接口");
         ScheduledFuture scheduledFuture = threadPoolTaskScheduler.schedule(task,(triggerContext -> new CronTrigger(sj.getCronExpression()).nextExecutionTime(triggerContext)));
         scheduledFutureMap.put(sj.getJobKey(),scheduledFuture);
     }
 
     @Override
     public void initTask() {
         List

2.8 上面用到的獲取Bean的工具類SpringContextUtil

@Component
 public class SpringContextUtil implements ApplicationContextAware {
 
 
     private static ApplicationContext applicationContext = null;
     @Override
     public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
         if(SpringContextUtil.applicationContext == null){
             SpringContextUtil.applicationContext  = applicationContext;
         }
     }
 
     public static ApplicationContext getApplicationContext() {
         return applicationContext;
     }
 
     public static Object getBean(String name){
         return getApplicationContext().getBean(name);
     }
 
     public static

2.9 表操作對應(yīng)的一些類

Pojo

@Data
 @TableName("scheduled_job")
 public class ScheduledJob {
 
     @TableId(value = "job_id",type = IdType.AUTO)
     private Integer jobId;
 
     private String jobKey;
 
     private String cronExpression;
 
     private String taskExplain;
 
     private Integer status;
 
 }

ScheduledJobMapper

public interface ScheduledJobMapper extends BaseMapper<ScheduledJob> {
 }

ScheduledJobService

public interface ScheduledJobService extends IService<ScheduledJob> {
 
     /**
      * 修改定時任務(wù)，并重新啟動
      * @param scheduledJob
      * @return
      */
     boolean updateOne(ScheduledJob scheduledJob);
 }

@Service
 @Slf4j
 public class ScheduledJobServiceImpl extends ServiceImpl

2.10 修改定時任務(wù)的接口

@RestController
 @RequestMapping("/job")
 public class ScheduledJobController {
 
     @Autowired
     private ScheduledJobService scheduledJobService;
 
     @PostMapping(value = "/update")
     public CallBackResult update(HttpServletRequest request, ScheduledJob scheduledJob){
          if(scheduledJobService.updateOne(scheduledJob))
              return new CallBackResult(true,"修改成功");
          return new CallBackResult(false,"修改失敗");
     }
 
 }

3、測試結(jié)果

3.1 啟動項目，看下定時任務(wù)的執(zhí)行結(jié)果，控制臺輸出結(jié)果

我們可以看到任務(wù)1是每5秒執(zhí)行一次，任務(wù)2是12秒執(zhí)行一次

3.2 修改任務(wù)1的cron參數(shù)或者狀態(tài)

3.2.1 修改cron，執(zhí)行周期改為20秒執(zhí)行一次，狀態(tài)不變

再看控制臺輸出結(jié)果，任務(wù)2沒變化，任務(wù)1由5秒一次變成了20秒一次了

3.2.1 修改狀態(tài)

再看控制臺輸出結(jié)果，任務(wù)2沒變化，任務(wù)1已經(jīng)不再執(zhí)行了

最后

第二種方式支持通過接口的方式去改動，并且不需要重啟，當(dāng)然啦，也可以直接在數(shù)據(jù)庫中添加或修改數(shù)據(jù)后重啟項目，配置更加靈活一點。

如果是一個固定的需求，執(zhí)行周期一定不會變的了，推薦還是第一種寫法，畢竟簡單嘛。

如果覺得寫得還不錯的話，給個推薦鼓勵一下吧。