redis 实现发布订阅的功能
redis 除了作为缓存的功能外还可以用作消息中间件的功能,这片博客主要是介绍一下 redis 整合spring 实现消息的发布和订阅功能;
1:redis依赖,依赖两个包,redis 包, spring-redis 包用于整合redis,这里就不介绍了,具体可以参考上一篇博客 :redis 缓存 中的介绍;
2:redis和spring的整合:
<bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig"> <property name="maxIdle" value="1" /> <property name="maxTotal" value="5" /> <property name="blockWhenExhausted" value="true" /> <property name="maxWaitMillis" value="30000" /> <property name="testOnBorrow" value="true" /> </bean> <bean id="jedisConnectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory"> <property name="hostName" value="localhost" /> <property name="port" value="6379"/> <property name="poolConfig" ref="jedisPoolConfig" /> <property name="usePool" value="true"/> </bean> <bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate"> <property name="connectionFactory" ref="jedisConnectionFactory" /> <property name="keySerializer"> <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" /> </property> <property name="valueSerializer"> <bean class="org.springframework.data.redis.serializer.JdkSerializationRedisSerializer" /> </property> <property name="hashKeySerializer"> <bean class="org.springframework.data.redis.serializer.StringRedisSerializer"/> </property> <property name="hashValueSerializer"> <bean class="org.springframework.data.redis.serializer.JdkSerializationRedisSerializer"/> </property> </bean> <!-- redis 消息发布订阅 --> <bean id="myRedisListener" class="bz.beppe.redis.MyRedisListener" scope="prototype"/> <!-- 这里配置线程池任务 --> <bean id="taskExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor"> <property name="corePoolSize" value="4"/> <property name="maxPoolSize" value="4"/> <property name="queueCapacity" value="100000"/> </bean> <!-- 配置redis container 将监听类注入到redis容器中,实现监听容器中指定 主题 队列的功能 --> <bean id="redisContainer" class="org.springframework.data.redis.listener.RedisMessageListenerContainer" destroy-method="destroy"> <property name="connectionFactory" ref="jedisConnectionFactory"/> <property name="taskExecutor"> <ref bean="taskExecutor" /> </property> <property name="messageListeners"> <map> <entry key-ref="myRedisListener"> <bean class="org.springframework.data.redis.listener.ChannelTopic"> <constructor-arg value="push:myredis"/> </bean> </entry> </map> </property> </bean>
3:监听类 该类只要实现 MessageListener 接口即可,并且在重写的方法中进行需要的业务处理:
public class MyRedisListener implements MessageListener{ @Override public void onMessage(Message message, byte[] pattern) { byte[] body = message.getBody(); byte[] channel = message.getChannel(); // redisTemplate.convertAndSend("push:myredis","this is the redis subscribe!!"); String channelStr = new String(channel); String bodyStr = new String(body); System.out.println("渠道为:"+channelStr+"消息为:"+bodyStr); //这里的业务处理只做简单的打印输出 } }
4:消息发布类:
在消息发布类中需要使用到 redisTemplate 来进行消息的发布,其中,消息发布的方法为 redisTemplate.convertAndSend(String channel,String mess);
需要指定消息发布的 通道名称,这里的通道和监听中配置的渠道名称一致 ;mess 就是你需要发布到该通道上的内容;
5:消息的发布:
@Test public void redisSubTest() throws InterruptedException { ApplicationContext ctx = new ClassPathXmlApplicationContext("spring-redis.xml"); RedisTemplate redisTemplate = (RedisTemplate) ctx.getBean("redisTemplate"); redisTemplate.convertAndSend("push:myredis","this is the redis subscribe!!"); Thread.sleep(5000); }
到这里为止,一个简单的基于redis的订阅发布就实现了,在项目中你可以根据你的具体业务来实现功能