Topic类型的Exchange与Direct相比，都是可以根据RoutingKey把消息路由到不同的队列。只不过Topic类型Exchange可以让队列在绑定Routing key 的时候使用通配符！
Routingkey 一般都是有一个或多个单词组成，多个单词之间以”.”分割，例如： snow.com
通配符规则：
#：匹配一个或多个词
*：匹配不多不少恰好1个词
举例：
snow.#：能够匹配snow.com.cn 或者 snow.com
snow.*：只能匹配snow.com
如下图:
解释：
- Queue1：绑定的是china.# ，因此凡是以 china.开头的routing key 都会被匹配到。包括china.news和china.weather
- Queue2：绑定的是#.news ，因此凡是以 .news结尾的 routing key 都会被匹配。包括china.news和japan.news
案例需求：
实现思路如下：
- 并利用 @RabbitListener 声明 Exchange、Queue、RoutingKey
- 在 consumer 服务中，编写两个消费者方法，分别监听 business.test.topic.queue1 和business.test.topic.queue2
- 在 publisher 中编写测试方法，向business.test.topic发送消息
pom
<dependencies> <!--RabbitMQ 依赖--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-amqp</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.47</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> </dependencies>
yml
server: port: 8080 spring: rabbitmq: host: **.***.**.*** port: 5672 username: **** password: ****
生产者
import org.springframework.amqp.rabbit.core.RabbitTemplate; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; /** * @author: Snow * @date: 2023/1/6 * ************************************************** * 修改记录(时间--修改人--修改说明): */ @RestController @RequestMapping("/topic") public class SendController { @Autowired private RabbitTemplate rabbitTemplate; @GetMapping("/send/{message}") public void send(@PathVariable("message") String message){ // 交换机名称 String exchangeName = "business.test.topic"; // 发送消息 if(message.contains("china") && message.contains("news")){ rabbitTemplate.convertAndSend(exchangeName, "china.news", message); return; } if(message.contains("china")){ rabbitTemplate.convertAndSend(exchangeName, "china.lala", message); return; } if(message.contains("news")){ rabbitTemplate.convertAndSend(exchangeName, "lalla.news", message); return; } } }
消费者
import org.springframework.amqp.core.ExchangeTypes; import org.springframework.amqp.rabbit.annotation.Exchange; import org.springframework.amqp.rabbit.annotation.Queue; import org.springframework.amqp.rabbit.annotation.QueueBinding; import org.springframework.amqp.rabbit.annotation.RabbitListener; import org.springframework.stereotype.Component; /** * @author: Snow * @date: 2023/1/6 * ************************************************** * 修改记录(时间--修改人--修改说明): */ @Component public class Consumer { @RabbitListener(bindings = @QueueBinding( value = @Queue(name = "business.test.topic.queue1"), exchange = @Exchange(name = "business.test.topic", type = ExchangeTypes.TOPIC), key = "china.#" )) public void listenTopicQueue1(String msg){ System.out.println("消费者接收到topic.queue1的消息：【" + msg + "】"); } @RabbitListener(bindings = @QueueBinding( value = @Queue(name = "business.test.topic.queue2"), exchange = @Exchange(name = "business.test.topic", type = ExchangeTypes.TOPIC), key = "#.news" )) public void listenTopicQueue2(String msg){ System.out.println("消费者接收到topic.queue2的消息：【" + msg + "】"); } }
