參考：
https://juejin.im/post/6844904150703013901

http://www.itdecent.cn/p/106f0eae07c8

redis key失效通知實現(xiàn)延遲隊列

redis.conf 增加配置

notify-keyspace-events Ex

  @Bean
   RedisMessageListenerContainer 
  container(@Qualifier("getConnectionFactory") 
    RedisConnectionFactory connectionFactory) {
   RedisMessageListenerContainer container = new 
   RedisMessageListenerContainer();
    container.setConnectionFactory(connectionFactory);
    return container;
}

@Component
public class RedisKeyExpirationListener extends KeyExpirationEventMessageListener {

   public RedisKeyExpirationListener(RedisMessageListenerContainer listenerContainer) {
       super(listenerContainer);
   }
   @Override
   public void onMessage(Message message, byte[] pattern) {
       String expiredKey = message.toString();

       System.out.println("監(jiān)聽***************************************************");
       System.out.println("監(jiān)聽到key：" + expiredKey + "已過期");
       System.out.println("監(jiān)聽***************************************************");
   }
}

問題：消息通知不能持久化，出現(xiàn)宕機情況，消息丟失

rabbitMq的死信隊列