Schedule定时任务在分布式产生的问题详解

 <parent>
     <artifactId>spring-boot-parent</artifactId>
     <groupId>org.springframework.boot</groupId>
     <version>2.7.2</version>
 </parent>
 <dependencies>
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot</artifactId>
     </dependency>
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter</artifactId>
     </dependency>
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-web</artifactId>
     </dependency>
     <dependency>
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
         </dependency>
  </dependencies>

 @SpringBootApplication
 public class ApplicationScheduling {
     public static void main(String[] args) {
         SpringApplication.run(ApplicationScheduling.class, args);
     }
 }

 /**
  * @description:
  * @author: Ning Zaichun
  * @date: 2022年09月06日 0:02
  */
 @Slf4j
 @Component
 @EnableScheduling
 public class ScheduleService {
     // 每五秒执行一次，cron的表达式就不再多说明了
     @Scheduled(cron = "0/5 * * * * ? ")
     public void testSchedule() {
             log.info("当前执行任务的线程号ID===>{}", Thread.currentThread().getId());
     }
 }

     @Scheduled(cron = "0/5 * * * * ? ")
     public void testSchedule() {
         try {
             Thread.sleep(10000);
             log.info("当前执行任务的线程号ID===>{}", Thread.currentThread().getId());
         } catch (Exception e) {
             e.printStackTrace();
         } 
     }

 @ConditionalOnClass(ThreadPoolTaskScheduler.class)
 @Configuration(proxyBeanMethods = false)
 @EnableConfigurationProperties(TaskSchedulingProperties.class)
 @AutoConfigureAfter(TaskExecutionAutoConfiguration.class)
 public class TaskSchedulingAutoConfiguration {
     @Bean
     @ConditionalOnBean(name = TaskManagementConfigUtils.SCHEDULED_ANNOTATION_PROCESSOR_BEAN_NAME)
     @ConditionalOnMissingBean({ SchedulingConfigurer.class, TaskScheduler.class, ScheduledExecutorService.class })
     public ThreadPoolTaskScheduler taskScheduler(TaskSchedulerBuilder builder) {
         return builder.build();
     }
    // ......
 }

 public ThreadPoolTaskScheduler build() {
     return configure(new ThreadPoolTaskScheduler());
 }

     protected ScheduledExecutorService createExecutor(
             int poolSize, ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler) 

 spring:
   task:
     scheduling:
       thread-name-prefix: nzc-schedule- #线程名前缀
       pool:
         size: 10 #核心线程数
      # shutdown:
      #  await-termination: true #执行程序是否应等待计划任务在关机时完成。
      #   await-termination-period:  #执行程序应等待剩余任务完成的最长时间。

 @Configuration
 public class MyTheadPoolConfig {
     @Bean
     public TaskExecutor taskExecutor() {
         ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
         //设置核心线程数
         executor.setCorePoolSize(10);
         //设置最大线程数
         executor.setMaxPoolSize(20);
         //缓冲队列200：用来缓冲执行任务的队列
         executor.setQueueCapacity(200);
         //线程活路时间 60 秒
         executor.setKeepAliveSeconds(60);
         //线程池名的前缀：设置好了之后可以方便我们定位处理任务所在的线程池
         // 这里我继续沿用 scheduling 默认的线程名前缀
         executor.setThreadNamePrefix("nzc-create-scheduling-");
         //设置拒绝策略
         executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
         executor.setWaitForTasksToCompleteOnShutdown(true);
         return executor;
     }
 }

 /**
  * @description:
  * @author: Ning Zaichun
  * @date: 2022年09月06日 0:02
  */
 @Slf4j
 @Component
 @EnableScheduling
 public class ScheduleService {
     @Autowired
     TaskExecutor taskExecutor;
     @Scheduled(cron = "0/5 * * * * ? ")
     public void testSchedule() {
         CompletableFuture.runAsync(()->{
             try {
                 Thread.sleep(10000);
                 log.info("当前执行任务的线程号ID===>{}", Thread.currentThread().getId());
             } catch (Exception e) {
                 e.printStackTrace();
             } 
         },taskExecutor);
     }
 }

 /**
  * @description:
  * @author: Ning Zaichun
  * @date: 2022年09月06日 0:02
  */
 @Slf4j
 @Component
 @EnableAsync
 @EnableScheduling
 public class ScheduleService {
     @Autowired
     TaskExecutor taskExecutor;
     @Async(value = "taskExecutor")
     @Scheduled(cron = "0/5 * * * * ? ")
     public void testSchedule() {
             try {
                 Thread.sleep(10000);
                 log.info("当前执行任务的线程号ID===>{}", Thread.currentThread().getId());
             } catch (Exception e) {
                 e.printStackTrace();
             } 
     }
 }

 /**
  * 定时任务
  *      1、@EnableScheduling 开启定时任务
  *      2、@Scheduled开启一个定时任务
  *      3、自动装配类 TaskSchedulingAutoConfiguration
  *
  * 异步任务
  *      1、@EnableAsync:开启异步任务
  *      2、@Async：给希望异步执行的方法标注
  *      3、自动装配类 TaskExecutionAutoConfiguration
  */

 <dependency>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-data-redis</artifactId>
 </dependency>
 <dependency>
     <groupId>org.redisson</groupId>
     <artifactId>redisson-spring-boot-starter</artifactId>
     <version>3.17.6</version>
 </dependency>

 /**
  * @description:
  * @author: Ning Zaichun
  * @date: 2022年09月06日 9:31
  */
 @Configuration
 public class MyRedissonConfig {
     /**
      * 所有对Redisson的使用都是通过RedissonClient
      * @return
      * @throws IOException
      */
     @Bean(destroyMethod="shutdown")
     public RedissonClient redissonClient() throws IOException {
         //1、创建配置
         Config config = new Config();
        // 这里规定要用 redis:// IP地址
           config.useSingleServer().setAddress("redis://xxxxx:6379").setPassword("000415");   // 有密码就写密码~ 木有不用写~
         //2、根据Config创建出RedissonClient实例
         //Redis url should start with redis:// or rediss://
         RedissonClient redissonClient = Redisson.create(config);
         return redissonClient;
     }
 }

 
 /**
  * @description:
  * @author: Ning Zaichun
  * @date: 2022年09月06日 0:02
  */
 @Slf4j
 @Component
 @EnableAsync
 @EnableScheduling
 public class ScheduleService {
     @Autowired
     TaskExecutor taskExecutor;
     @Autowired
     RedissonClient redissonClient;
     private final String SCHEDULE_LOCK = "schedule:lock";
     @Async(value = "taskExecutor")
     @Scheduled(cron = "0/5 * * * * ? ")
     public void testSchedule() {
         //分布式锁
         RLock lock = redissonClient.getLock(SCHEDULE_LOCK);
         try {
             //加锁 10 为时间，加上时间 默认会去掉 redisson 的看门狗机制（即自动续锁机制）
             lock.lock(10, TimeUnit.SECONDS);
             Thread.sleep(10000);
             log.info("当前执行任务的线程号ID===>{}", Thread.currentThread().getId());
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             // 一定要记得解锁~
             lock.unlock();
         }
     }
 }