5. RabbitMQ 消息队列中 Exchanges(交换机) 的详细说明

bindingKeyEntry : bindingKeyMap.entrySet()) {

        String routingKey = bindingKeyEntry.getKey();
        String message = bindingKeyEntry.getValue();
        channel.basicPublish(EXCHANGE_NAME, routingKey, null, message.getBytes("UTF-8"));
        System.out.println("生产者发出消息: " + message);

}

}

}

**编写一个消费者，仅仅读取：`Routing key 为 *.orange.*` 匹配的队列的消息**
![在这里插入图片描述](https://cdn.res.knowhub.vip/c/2504/04/21f9ed5d.png?G1cAAMTsdJxIEq%2bi26hD2jvFHc2ARRpBpYT1es9Z%2byb6fldWxGe0Pn1%2f%2bE3r0ymxwRSkrJmBEBhSJIOrIQi0mF2pIq7h)
```csharp
package com.rainbowsea.rabbitmq.seven;
import com.rabbitmq.client.BuiltinExchangeType;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DeliverCallback;
import com.rainbowsea.rabbitmq.utils.RabbitMQUtils;
import java.io.IOException;
import java.util.concurrent.TimeoutException;
public class ReceiveLogsTopic01 {
// 交换机名为 : topic_logs
    private static final String EXCHANGE_NAME = "topic_logs";
public static void main(String[] args) throws IOException, TimeoutException {
        Channel channel = RabbitMQUtils.getChannel();
// 声明一个交换机 BuiltinExchangeType.TOPIC(主题)
        channel.exchangeDeclare(EXCHANGE_NAME, BuiltinExchangeType.TOPIC);
// 声明一个队列,队列名为 Q1
        String queueName = "Q1";
        channel.queueDeclare(queueName, false, false, false, null);
        // 绑定交换机与队列, 该 Q1 队列的 Routing key 为 *.orange.*
        channel.queueBind(queueName, EXCHANGE_NAME, "*.orange.*");
System.out.println("Q1 等待接收消息，把接收到消息打印在屏幕上...");
// 接收消息
        DeliverCallback deliverCallback = (consumerTag, message) -> {
            System.out.println("Q1 接收到的消息" + new String(message.getBody(), "UTF-8"));
            System.out.println("Q1 接收队列:" + queueName + "绑定键" + message.getEnvelope().getRoutingKey());
};
// 消费者取消消息时回调接口
        // 第一个参数，队列 queueName
        channel.basicConsume(queueName, true, deliverCallback, consumerTage -> {
        });
    }
}

编写一个消费者，仅仅读取：Routing key 为 *.orange.* 和 "lazy.#" 匹配的队列的消息

package com.rainbowsea.rabbitmq.seven;
import com.rabbitmq.client.BuiltinExchangeType;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DeliverCallback;
import com.rainbowsea.rabbitmq.utils.RabbitMQUtils;
import java.io.IOException;
import java.util.concurrent.TimeoutException;
public class ReceiveLogsTopic02 {
// 交换机名为 : topic_logs
    private static final String EXCHANGE_NAME = "topic_logs";
public static void main(String[] args) throws IOException, TimeoutException {
        Channel channel = RabbitMQUtils.getChannel();
// 声明一个交换机 BuiltinExchangeType.TOPIC(主题)
        channel.exchangeDeclare(EXCHANGE_NAME, BuiltinExchangeType.TOPIC);
// 声明一个队列,队列名为 Q2
        String queueName = "Q2";
        channel.queueDeclare(queueName, false, false, false, null);
        // 绑定交换机与队列, 该 Q2 队列的 Routing key 为 *.orange.* 和 "lazy.#"
        channel.queueBind(queueName, EXCHANGE_NAME, "*.*.rabbit");
        channel.queueBind(queueName, EXCHANGE_NAME, "lazy.#");
System.out.println("Q2 等待接收消息，把接收到消息打印在屏幕上...");
// 接收消息
        DeliverCallback deliverCallback = (consumerTag, message) -> {
            System.out.println("Q2 接收到的消息" + new String(message.getBody(), "UTF-8"));
            System.out.println("Q2 接收队列:" + queueName + "绑定键" + message.getEnvelope().getRoutingKey());
};
// 消费者取消消息时回调接口
        // 第一个参数，队列 queueName
        channel.basicConsume(queueName, true, deliverCallback, consumerTage -> {
        });
    }
}

运行执行效果： > > > 从运行结果上看，我们可以明显的看到，消费者根据对应的 Routing key 匹配而读取，对应的消息队列上的消息内容。 >