RabbitMQ简单应用の主题模式（topic）

Topic exchange（主题转发器）

发送给主题转发器的消息不能是任意设置的选择键，必须是用小数点隔开的一系列的标识符。这些标识符可以是随意，但是通常跟消息的某些特性相关联。一些合法的路由选择键比如“socket.usd.nyse”,"nyse.vmw","quick.orange.rabbit"，你愿意用多少单词都可以，只要不超过上限的255个字节。

绑定键也必须以相同的格式。主题转发器的逻辑类似于direct类型的转发器。消息通过一个特定的路由键发送到所有与绑定键匹配的队列中。需要注意的是，关于绑定键有两种特殊的情况：*（星号）可以代替一个任意标识符 ；#（井号）可以代替零个或多个标识符。如下图：

MQ工厂连接类Connection

 package com.mmr.rabbitmq.util;

 import java.io.IOException;

 import com.rabbitmq.client.Connection;
 import com.rabbitmq.client.ConnectionFactory;

 public class ConnectionUtils {
     /**
      * @desc 获取Mq 的链接
      * @author zp
      * @throws IOException
      * @date 2018-7-19
      */
     public static  Connection getConnection() throws IOException {
         // 1.定义一个链接工厂
         ConnectionFactory factroy = new ConnectionFactory();

         // 2.设置服务地址
         factroy.setHost("127.0.0.1");

         // 3.设置端口号
         factroy.setPort(5672);

         // 4.vhost  设置数据库
         factroy.setVirtualHost("vhtest");

         // 5.设置用户名
         factroy.setUsername("jerry");

         // 6. 设置密码
         factroy.setPassword("123456");

         // 7.返回链接
         return factroy.newConnection();
     }
 }

MQ消息生产者类Send

 package com.mmr.rabbitmq.topic;

 import java.io.IOException;

 import com.mmr.rabbitmq.util.ConnectionUtils;
 import com.rabbitmq.client.Channel;
 import com.rabbitmq.client.Connection;

 public class Send {
     private static final String EXCHANGE_TOPIC_NAME = "test_exchange_topic";
     public static void main(String[] args) throws IOException {
         // 创建连接
         Connection connection = ConnectionUtils.getConnection();

         // 获取通道
         Channel channel = connection.createChannel();

         // 设置路由键
         channel.exchangeDeclare(EXCHANGE_TOPIC_NAME, "topic");

         // 发送消息
         String msg = "商品.......";

         // String routingKey = "goods.delete";

         channel.basicPublish(EXCHANGE_TOPIC_NAME, "goods.add", null, msg.getBytes());
         System.out.println("send ---"+msg);
         channel.close();
         connection.close();

     }
 }

MQ消息消费者类Recv1只处理good.add good.edit  ；Recv2处理good.#

 package com.mmr.rabbitmq.topic;

 import java.io.IOException;

 import com.mmr.rabbitmq.util.ConnectionUtils;
 import com.rabbitmq.client.Channel;
 import com.rabbitmq.client.Connection;
 import com.rabbitmq.client.Consumer;
 import com.rabbitmq.client.DefaultConsumer;
 import com.rabbitmq.client.Envelope;
 import com.rabbitmq.client.AMQP.BasicProperties;

 public class Recv1 {
     private static final String QUEUE_NAME="test_queue_topic1";
     private static final String EXCHANGE_TOPIC_NAME = "test_exchange_topic";
     public static void main(String[] args) throws IOException {
         // 创建连接
         Connection connection = ConnectionUtils.getConnection();

         // 创建通道
         final Channel channel = connection.createChannel();

         // 队列声明
         channel.queueDeclare(QUEUE_NAME, false, false, false, null);

         // 绑定交换机
         channel.queueBind(QUEUE_NAME, EXCHANGE_TOPIC_NAME, "goods.add");
         channel.queueBind(QUEUE_NAME, EXCHANGE_TOPIC_NAME, "goods.edit");
         // 每次
         channel.basicQos(1);

         // 消费者
         Consumer consumer = new DefaultConsumer(channel){
             @Override
             public void handleDelivery(String consumerTag, Envelope envelope,
                     BasicProperties properties, byte[] body) throws IOException {
                 // TODO Auto-generated method stub
                 // 接收消息
                 String msg = new String(body,"utf-8");
                 System.out.println("【1】Recv1 msg"+msg);
                 try {
                     Thread.sleep(2000);
                 } catch (Exception e) {
                     // TODO: handle exception
                     e.printStackTrace();
                 }finally{
                     System.out.print("【1】Recv1 done");
                     //回执单
                     channel.basicAck(envelope.getDeliveryTag(), false);
                 }
             }
         };
         boolean autoAck = false;
         channel.basicConsume(QUEUE_NAME, autoAck,consumer );
     }
 }

 package com.mmr.rabbitmq.topic;

 import java.io.IOException;

 import com.mmr.rabbitmq.util.ConnectionUtils;
 import com.rabbitmq.client.Channel;
 import com.rabbitmq.client.Connection;
 import com.rabbitmq.client.Consumer;
 import com.rabbitmq.client.DefaultConsumer;
 import com.rabbitmq.client.Envelope;
 import com.rabbitmq.client.AMQP.BasicProperties;

 public class Recv2 {
     private static final String QUEUE_NAME="test_queue_topic2";
     private static final String EXCHANGE_TOPIC_NAME = "test_exchange_topic";
     public static void main(String[] args) throws IOException {
         // 创建连接
         Connection connection = ConnectionUtils.getConnection();

         // 创建通道
         final Channel channel = connection.createChannel();

         // 队列声明
         channel.queueDeclare(QUEUE_NAME, false, false, false, null);

         // 绑定交换机
         channel.queueBind(QUEUE_NAME, EXCHANGE_TOPIC_NAME, "goods.#"); 

         // 每次
         channel.basicQos(1);

         // 消费者
         Consumer consumer = new DefaultConsumer(channel){
             @Override
             public void handleDelivery(String consumerTag, Envelope envelope,
                     BasicProperties properties, byte[] body) throws IOException {
                 // TODO Auto-generated method stub
                 // 接收消息
                 String msg = new String(body,"utf-8");
                 System.out.println("【2】Recv2 msg"+msg);
                 try {
                     Thread.sleep(2000);
                 } catch (Exception e) {
                     // TODO: handle exception
                     e.printStackTrace();
                 }finally{
                     System.out.println("【2】Recv2 done");
                     //回执单
                     channel.basicAck(envelope.getDeliveryTag(), false);
                 }
             }
         };
         boolean autoAck = false;
         channel.basicConsume(QUEUE_NAME, autoAck,consumer );
     }
 }

运行上述代码，可以获得  当消息产生发送过来是good.add/good.edit 那么消息消费者1和消费者2都会接收到消息并且处理，但是当消息生产者发送过来的是good.delete或者good.select等的时候只有消费者2（Recv2）接收到消息处理通知。