/** * 用于spring session，防止每次創建一個線程 * @return */@Beanpublic ThreadPoolTaskExecutor springSessionRedisTaskExecutor(){  ThreadPoolTaskExecutor springSessionRedisTaskExecutor = new ThreadPoolTaskExecutor();  springSessionRedisTaskExecutor.setCorePoolSize(8);  springSessionRedisTaskExecutor.setMaxPoolSize(16);  springSessionRedisTaskExecutor.setKeepAliveSeconds(10);  springSessionRedisTaskExecutor.setQueueCapacity(1000);  springSessionRedisTaskExecutor.setThreadNamePrefix("Spring session redis executor thread: ");  return springSessionRedisTaskExecutor;}

@Autowired(  required = false  //該處理監聽的線程池不是必須的，如果不自定義默認將使用SimpleAsyncTaskExecutor線程池)@Qualifier("springSessionRedisTaskExecutor")public void setRedisTaskExecutor(Executor redisTaskExecutor) {  this.redisTaskExecutor = redisTaskExecutor;}

@Beanpublic RedisMessageListenerContainer redisMessageListenerContainer() {  RedisMessageListenerContainer container = new RedisMessageListenerContainer();  container.setConnectionFactory(this.redisConnectionFactory);  if (this.redisTaskExecutor != null) {    container.setTaskExecutor(this.redisTaskExecutor);  }  if (this.redisSubscriptionExecutor != null) {    container.setSubscriptionExecutor(this.redisSubscriptionExecutor);  }  container.addMessageListener(this.sessionRepository(), Arrays.asList(new PatternTopic("__keyevent@*:del"), new PatternTopic("__keyevent@*:expired")));  container.addMessageListener(this.sessionRepository(), Collections.singletonList(new PatternTopic(this.sessionRepository().getSessionCreatedChannelPrefix() + "*")));  return container;}RedisMessageListenerContainer正是處理監聽的類，RedisMessageListenerContainer設置了不為空的redisTaskExecutor，因為spring session默認沒有配置該Executor，那RedisMessageListenerContainer在處理監聽時怎么使用線程呢？我們接著看RedisMessageListenerContainer的源碼：public void afterPropertiesSet() {  if (this.taskExecutor == null) {    this.manageExecutor = true;    this.taskExecutor = this.createDefaultTaskExecutor();  }  if (this.subscriptionExecutor == null) {    this.subscriptionExecutor = this.taskExecutor;  }  this.initialized = true;}protected TaskExecutor createDefaultTaskExecutor() {  String threadNamePrefix = this.beanName != null ? this.beanName + "-" : DEFAULT_THREAD_NAME_PREFIX;  return new SimpleAsyncTaskExecutor(threadNamePrefix);}