SpringCloud分布式微服务b2b2c电子商务-在springboot中用redis实现消息队

准备阶段
安装redis,可参考我的另一篇文章
java 1.8
maven 3.0
idea
环境依赖
创建一个新的springboot工程，了解springcloud架构可以加求求：三五三六二四七二五九。在其pom文件,加入spring-boot-starter-data-redis依赖：

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

创建一个消息接收者
REcevier类，它是一个普通的类，需要注入到springboot中。

public class Receiver {
    private static final Logger LOGGER = LoggerFactory.getLogger(Receiver.class);

    private CountDownLatch latch;

    @Autowired
    public Receiver(CountDownLatch latch) {
        this.latch = latch;
    }

    public void receiveMessage(String message) {
        LOGGER.info("Received <" + message + ">");
        latch.countDown();
    }
}

注入消息接收者

@Bean
    Receiver receiver(CountDownLatch latch) {
        return new Receiver(latch);
    }

    @Bean
    CountDownLatch latch() {
        return new CountDownLatch(1);
    }

    @Bean
    StringRedisTemplate template(RedisConnectionFactory connectionFactory) {
        return new StringRedisTemplate(connectionFactory);
    }

注入消息监听容器
在spring data redis中，利用redis发送一条消息和接受一条消息，需要三样东西：

一个连接工厂
一个消息监听容器
Redis template
上述1、3步已经完成，所以只需注入消息监听容器即可：

@Bean
    RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory,
                                            MessageListenerAdapter listenerAdapter) {

        RedisMessageListenerContainer container = new RedisMessageListenerContainer();
        container.setConnectionFactory(connectionFactory);
        container.addMessageListener(listenerAdapter, new PatternTopic("chat"));

        return container;
    }

    @Bean
    MessageListenerAdapter listenerAdapter(Receiver receiver) {
        return new MessageListenerAdapter(receiver, "receiveMessage");
    }

测试
在springboot入口的main方法：

public static void main(String[] args) throws Exception{
        ApplicationContext ctx =  SpringApplication.run(SpringbootRedisApplication.class, args);

        StringRedisTemplate template = ctx.getBean(StringRedisTemplate.class);
        CountDownLatch latch = ctx.getBean(CountDownLatch.class);

        LOGGER.info("Sending message...");
        template.convertAndSend("chat", "Hello from Redis!");

        latch.await();

        System.exit(0);
    }