為了演示Topic模式，所以模擬一個需求：

用戶A想接收開封市的天氣
用戶B想接收開封市的新聞
用戶C想接收開封市的新聞和天氣

1.創建基于SpringBoot的生產者模塊和消費者模塊，兩個模塊結構相同，在hello包下創建SpringBoot主啟動類。

2.引入starter

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
        <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
    </dependencies>

3.在resources包下創建application.yml文件，內容如下(根據實際情況填寫地址用戶名密碼等等)：

4.在生產者模塊創建config包,在此包下創建一個配置類(功能是聲明隊列，聲明交換機，聲明RoutingKey,聲明隊列和交換機的綁定關系)，結構和內容如下：

package com.hello.config;

import org.springframework.amqp.core.*;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class RabbitMQConfig {
    //為了方便演示我都使用的public
    //隊列
    public static final String QUEUE_NEWS = "queue_news";
    public static final String QUEUE_WEATHER = "queue_weather";
    public static final String QUEUE_NEWS_WEATHER = "queue_news_weather";
    //交換機
    public static final String EXCHANGE_TOPIC_KAIFENG = "exchange_topic_kaifeng";
    //交換機與隊列綁定的RoutingKey
    public static final String ROUTINGKEY_NEWS = "*.news";
    public static final String ROUTINGKEY_WEATHER = "*.weather";
    public static final String ROUTINGKEY_ALL = "kaifeng.*";

    //聲明隊列
    @Bean(QUEUE_NEWS)
    public Queue QUEUE_NEWS(){    //新聞的隊列
        return new Queue(QUEUE_NEWS);
    }
    @Bean(QUEUE_WEATHER)
    public Queue QUEUE_WEATHER(){  //天氣的隊列
        return new Queue(QUEUE_WEATHER);
    }
    @Bean(QUEUE_NEWS_WEATHER)
    public Queue QUEUE_NEWS_WEATHER(){  //新聞和天氣的隊列
        return new Queue(QUEUE_NEWS_WEATHER);
    }

    //聲明交換機
    @Bean(EXCHANGE_TOPIC_KAIFENG)
    public Exchange EXCHANGE_TOPIC_INFORM(){
        //聲明了一個Topic類型的交換機，durable是持久化（重啟rabbitmq這個交換機不會被自動刪除）
        return ExchangeBuilder.topicExchange(EXCHANGE_TOPIC_KAIFENG).durable(true).build();
    }

    //聲明news隊列和交換機綁定關系，并且指定RoutingKey
    @Bean
    public Binding NEWS_BINDING_TOPIC(@Qualifier(QUEUE_NEWS) Queue queue,
                                      @Qualifier(EXCHANGE_TOPIC_KAIFENG) Exchange exchange){
        return BindingBuilder.bind(queue).to(exchange).with(ROUTINGKEY_NEWS).noargs();
    }
    //聲明weather隊列和交換機綁定關系，并且指定RoutingKey
    @Bean
    public Binding WEATHER_BINDING_TOPIC(@Qualifier(QUEUE_WEATHER) Queue queue,
                                      @Qualifier(EXCHANGE_TOPIC_KAIFENG) Exchange exchange){
        return BindingBuilder.bind(queue).to(exchange).with(ROUTINGKEY_WEATHER).noargs();
    }
    //聲明news+weather隊列和交換機綁定關系，并且指定RoutingKey
    @Bean
    public Binding NEWS_WEATHER_BINDING_TOPIC(@Qualifier(QUEUE_NEWS_WEATHER) Queue queue,
                                       @Qualifier(EXCHANGE_TOPIC_KAIFENG) Exchange exchange){
        return BindingBuilder.bind(queue).to(exchange).with(ROUTINGKEY_ALL).noargs();
    }
}

5. 在測試類發送消息

@SpringBootTest
@RunWith(SpringRunner.class)
public class RabbitTest {
    @Autowired
    private RabbitTemplate rabbitTemplate;

    @Test
    public void sendNews(){
        //指定交換機，指定routing key，發送消息的內容
        rabbitTemplate.convertAndSend(RabbitMQConfig.EXCHANGE_TOPIC_KAIFENG,"kaifeng.news","開封今年糧食產量提升10%");
    }
    @Test
    public void sendWeather(){
        //指定交換機，指定routing key，發送消息的內容
        rabbitTemplate.convertAndSend(RabbitMQConfig.EXCHANGE_TOPIC_KAIFENG,"kaifeng.weather","開封明天白天多云15℃");
    }
}

6.當前整個結構如下

目的.png

7.我們也可以Rabbit網頁管理平臺上面查看隊列和交換機都已經創建,交換機綁定的隊列關系也已經綁定,消息因為沒有消費者所以也是存儲在MQ中。

交換機和隊列的綁定關系

7.在消費者模塊創建一個類MQConsumer接收消息

123.png

內容如下:

package com.hello.mq;

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

@Component
public class MQConsumer {
   //模擬三個用戶接收
   @RabbitListener(queues = {"queue_weather"})
   public void getMessageA(String msg){
       System.out.println("A用戶想看天氣接收到:" + msg);
   }
   @RabbitListener(queues = {"queue_news"})
   public void getMessageB(Message message){  //我們也可以用Message作為參數接收
       byte[] body = message.getBody();
       String msg = new String(body);
       System.out.println("B用戶想看新聞接收到:" + msg);
   }
   @RabbitListener(queues = {"queue_news_weather"})
   public void getMessageC(String msg){
       System.out.println("C用戶想看新聞和天氣接收到:" + msg);
   }
}

運行消費者程序收到消息打印的結果:

打印結果