RabbitMQ实例（三）——使用direct方式，带有Routingkey方式

妖狐艹你老母 2022-06-10 13:41 184阅读 0赞

# RabbitMQ实例（三）——使用direct方式，带有Routingkey方式 #

本文主要介绍的是使用direct方式的Exchange来进行发布和订阅。

direct方式的exchange首先需要制定direct方式，然后需要指定routingkey，最后绑定消费关系，然后开始发布和订阅。下面看一下官方的例子。

发布：

package com.xueyou.demo;
    
    import com.rabbitmq.client.Channel;
    import com.rabbitmq.client.Connection;
    import com.rabbitmq.client.ConnectionFactory;
    
    /**
     * Created by wuxueyou on 2017/8/20.
     */
    public class AppPublishWithRouting {
        private final static String EXCHANGE_NAME = "direct-logs";
    
        public static void main(String[] args) throws Exception {
            ConnectionFactory factory = new ConnectionFactory();
            factory.setHost("192.168.0.99");
            factory.setPort(5672);
            factory.setUsername("admin");
            factory.setPassword("admin");
            Connection connection = factory.newConnection();
            Channel channel = connection.createChannel();
            channel.exchangeDeclare(EXCHANGE_NAME, "direct");
    
            String message = "black message";
            channel.basicPublish(EXCHANGE_NAME, "black", null, message.getBytes());
            System.out.println(message);
            String message2 = "red message";
            channel.basicPublish(EXCHANGE_NAME, "red", null, message2.getBytes());
            System.out.println(message2);
            channel.close();
            connection.close();
        }
    }

package com.xueyou.demo;
    
    import com.rabbitmq.client.*;
    
    import java.io.IOException;
    
    /**
     * Created by wuxueyou on 2017/8/20.
     */
    public class AppSubScribeWithRouting {
        private final static String EXCHANGE_NAME = "direct-logs";
    
        public static void main(String[] args) throws Exception {
            ConnectionFactory factory = new ConnectionFactory();
            factory.setHost("192.168.0.99");
            factory.setPort(5672);
            factory.setUsername("admin");
            factory.setPassword("admin");
            Connection connection = factory.newConnection();
            Channel channel = connection.createChannel();
    
            channel.exchangeDeclare(EXCHANGE_NAME, "direct");
            String queueName = channel.queueDeclare().getQueue();
    
            channel.queueBind(queueName, EXCHANGE_NAME, "black");
    
            Consumer consumer = new DefaultConsumer(channel) {
                @Override
                public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
                    String message = new String(body, "UTF-8");
                    System.out.println("receive message :" + message);
                }
            };
            channel.basicConsume(queueName, true, consumer);
        }
    }

这里发布和订阅的时候都需要指定要生产到哪里和要从哪里消费，也就是说routingkey。那么routingkey可以指定多个吗？是可以的。如图：

![Center][]

能够看到，一个channel是可以有多个routingkey的，这样能够灵活的指定发布和订阅消息。  
具体的关系，可以看下图：

![Center 1][]

[Center]: /images/20220610/819814b439f140fcad214b9f308d70b2.png
[Center 1]: /images/20220610/eb859dcbbfc9407c9560b2e628a2fd3a.png