利用SpringAMQP演示FanoutExchange的使用（发布订阅：广播）

1、在消费者服务中，利用代码声明队列、交换机，并将两者绑定

在消费者服务中创建MQConfig，配置类：

package cn.itheima.mq;

import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.FanoutExchange;
import org.springframework.amqp.core.Queue;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * MQ的配置类
 *
 * @author ning
 * @since 2022/12/2 21:48
 */

@Configuration
public class MQConfig {
    //创建一个Fanout交换机
    @Bean
    public FanoutExchange fanoutExchange(){
        return new FanoutExchange("exchange.fanout");
    }

    //创建一个Fanout队列1
    @Bean
    public Queue queue1(){
        return new Queue("fanout.queue1");
    }

    //创建一个Fanout队列2
    @Bean
    public Queue queue2(){
        return new Queue("fanout.queue2");
    }

    //绑定对列1
    @Bean
    public Binding binding1(FanoutExchange fanoutExchange,Queue queue1){
        return BindingBuilder.bind(queue1).to(fanoutExchange);
    }

    //绑定对列2
    @Bean
    public Binding binding2(FanoutExchange fanoutExchange,Queue queue2){
        return BindingBuilder.bind(queue2).to(fanoutExchange);
    }
}

2、在消费者服务中，编写两个消费者方法，分别监听fanout.queue1和fanout.queue2

在listener包下创建SpringFanoutRabbitListener类：

package cn.itheima.mq.listener;

import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.stereotype.Component;

/**
 * 接收消息
 * @author ning
 * @since 2022/12/2 20:31
 */

@Component
public class SpringFanoutRabbitListener {

    //声明要监听的队列
    //可以监听多个队列
    //监听一个：queues = ""
    //监听多个：queues = {""}
    @RabbitListener(queues = "fanout.queue1")
    public void listenFanoutQueue1(String msg) {
        System.out.println("消费者1接受到了消息" + msg);
    }

    //声明要监听的队列
    //可以监听多个队列
    //监听一个：queues = ""
    //监听多个：queues = {""}
    @RabbitListener(queues = "fanout.queue2")
    public void listenFanoutQueue2(String msg) {
        System.out.println("消费者2接受到了消息" + msg);
    }
}

3、在生产者服务中，编写测试方法，向exchange.fanout发送消息

package cn.itheima.mq.helloworld;

import org.junit.jupiter.api.Test;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

/**
 * 发送消息测试类
 *
 * @author ning
 * @since 2022/12/2 20:09
 */

@SpringBootTest
public class SpringAmqpFanoutTest {

    //注入收发消息模板
    @Autowired
    private RabbitTemplate rabbitTemplate;

    @Test
    void testSimpleFanoutQueue() {
        //消息
        String msg = "hello, spring amqp!";
        //交换机名称
        String exchangeName = "exchange.fanout";
        //发送消息,转成字节数组发送
        //给交换机发送消息是三个参数
        rabbitTemplate.convertAndSend(exchangeName,"",msg);

        System.out.println("消息发送完毕");
    }
}

4、测试结果：