java 监听 redis 过期事件

淡淡的烟草味﹌ 2022-09-06 00:22 229阅读 0赞

1、引用redis的包

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

2、配置redis监听容器

import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.data.redis.connection.RedisConnectionFactory;
    import org.springframework.data.redis.listener.RedisMessageListenerContainer;
    
    @Configuration
    public class RedisListenerConfig {
        //from fhadmin.cn
        @Bean
        RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory) {
            RedisMessageListenerContainer container = new RedisMessageListenerContainer();
            container.setConnectionFactory(connectionFactory);
            return container;
        }
    }

3、创建redis过期监听

@Component
    public class RedisKeyExpirationListener extends KeyExpirationEventMessageListener {
        //from fhadmin.cn
        @Override
        public void onMessage(Message message, byte[] pattern) {
            // 过期key
            String expiredKey = message.toString();
            System.out.println(expiredKey + "过期了");
            // 下面可以通过redis工具获取值或者执行业务逻辑
        }
    
        public RedisKeyExpirationListener(RedisMessageListenerContainer redisMessageListenerContainer ){
            super(redisMessageListenerContainer);
        }
    }

4、测试是否可行

这个时候你可以搞个api测试下，设置过期事件为30秒，看下当key过期时，是否会正常被监听到。

5、注意事项

注意：监听器能监听到redis中过期的key是有个要求的，必须在redis配置文件里面设置能够监听到key过期事件，配置文件去目录下找，配置如下：

[![image-20210604235727511][]][image-20210604235727511 1]

[image-20210604235727511]: /images/20220829/1a40dda47de14f018469d87aadb882a2.png
[image-20210604235727511 1]: https://www.oschina.net/action/GoToLink?url=https%3A%2F%2Fimg2020.cnblogs.com%2Fother%2F1511231%2F202108%2F1511231-20210811115939082-787010532.png