RabbitMQ 六种基本队列模式 ----- 路由(routing)

在之前的消息 订阅/发布 模式中已经实现了通过 Fanout 来向所有的接受者广播，在 routing 中就是在 订阅/发布 中增加指定发送的 routing key 即可。下面的图也来自于官方的实例，Q1 和 Q2 绑定到了 X 的交换机上边，Q1 绑定了 orage 的 routing key ，Q2 绑定了 black 和 green 两个 routing key。这样在 p 使用 routing key 为 orange 发送时只有 Q1 会接收到消息。Q2 会将此消息抛弃。

使用 Java 来实现 发送者 和 接收者

• 第一步当然还是导入 Maven 坐标。

  <!-- https://mvnrepository.com/artifact/com.rabbitmq/amqp-client -->
  <dependency>
      <groupId>com.rabbitmq</groupId>
      <artifactId>amqp-client</artifactId>
      <version>5.9.0</version>
  </dependency>
  
  <!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-simple -->
  <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-simple</artifactId>
      <version>1.7.25</version>
  <!--            <scope>test</scope>-->
  </dependency>
  

• 创建发送者端

  		private static final String EXCHANGE_NAME = "logs_routing";
  
      public static void main(String[] args) {
          try {
              ConnectionFactory factory = new ConnectionFactory();
              // 设置参数
              factory.setHost("192.168.3.64");
              factory.setPort(5672);
              factory.setVirtualHost("/default_virtual_host");
              factory.setUsername("admin");
              factory.setPassword("admin");
  
              Connection connection = factory.newConnection();
              Channel channel = connection.createChannel();
              // 创建交换机 此处不能用 FANOUT 作为交换机的类型了 ，需要换成 DIRECT
              channel.exchangeDeclare(EXCHANGE_NAME, BuiltinExchangeType.DIRECT, true, false, false, null);
              // 声明两个队列
              channel.queueDeclare("log_fanout_queue1", false, false, false, null);
              channel.queueDeclare("log_fanout_queue2", false, false, false, null);
              // 绑定两个队列 (此处必须要要指定 routingkey)
              // 队列1只接收 info
              channel.queueBind("log_fanout_queue1", EXCHANGE_NAME, "info");
              // 队列2接收所有
              channel.queueBind("log_fanout_queue2", EXCHANGE_NAME, "info");
              channel.queueBind("log_fanout_queue2", EXCHANGE_NAME, "warn");
              channel.queueBind("log_fanout_queue2", EXCHANGE_NAME, "error");
  
              String message = "[日志][支付信息][订单号:" + new Date().getTime() + "][支付ID:10]";
              // 由于要使用 routing 模式发送所以就需要执行 routingkey
              channel.basicPublish(EXCHANGE_NAME, "info", null, message.getBytes(StandardCharsets.UTF_8));
              channel.basicPublish(EXCHANGE_NAME, "error", null, message.getBytes(StandardCharsets.UTF_8));
              // 释放资源
              channel.close();
              connection.close();
          } catch (IOException | TimeoutException e) {
              e.printStackTrace();
          }
      }
  

• 创建第一个接受者

  private static final String EXCHANGE_NAME = "logs_routing";
  
      public static void main(String[] args) {
          try {
              ConnectionFactory factory = new ConnectionFactory();
              // 设置参数
              factory.setHost("192.168.3.64");
              factory.setPort(5672);
              factory.setVirtualHost("/default_virtual_host");
              factory.setUsername("admin");
              factory.setPassword("admin");
  
              Connection connection = factory.newConnection();
  
              Channel channel = connection.createChannel();
              channel.exchangeDeclare(EXCHANGE_NAME,
                      BuiltinExchangeType.DIRECT,
                      true,
                      false,false,
                      null);
  
              String queue1Name = "log_direct_queue1";
              DeliverCallback deliverCallback = (consumerTag, delivery) -> {
                  String message = new String(delivery.getBody(), StandardCharsets.UTF_8);
                  System.out.println(" [info] Received '" + message + "'");
              };
              channel.basicConsume(queue1Name, true, deliverCallback, consumerTag -> {
              });
          } catch (IOException | TimeoutException e) {
              e.printStackTrace();
          }
  
      }
  

• 创建第二个接受者

  private static final String EXCHANGE_NAME = "logs_routing";
  
      public static void main(String[] args) {
          try {
              ConnectionFactory factory = new ConnectionFactory();
              // 设置参数
              factory.setHost("192.168.3.64");
              factory.setPort(5672);
              factory.setVirtualHost("/default_virtual_host");
              factory.setUsername("admin");
              factory.setPassword("admin");
  
              Connection connection = factory.newConnection();
  
              Channel channel = connection.createChannel();
              channel.exchangeDeclare(EXCHANGE_NAME,
                      BuiltinExchangeType.DIRECT,
                      true,
                      false,false,
                      null);
  
              String queue1Name = "log_direct_queue2";
              DeliverCallback deliverCallback = (consumerTag, delivery) -> {
                  String message = new String(delivery.getBody(), StandardCharsets.UTF_8);
                  System.out.println(" [info,error,warn] Received '" + message + "'");
              };
              channel.basicConsume(queue1Name, true, deliverCallback, consumerTag -> {
              });
          } catch (IOException | TimeoutException e) {
              e.printStackTrace();
          }
  
      }
  

  在发送者发送消息到指定的队列这时候两个接受者返回的消息为

  

  

  通过查看以上代码可以看出这个和 pub/sub 方式是一样，只不过是把广播模式切换成了指定方向的发送。然后在通道上绑定队列的时候要指定 routingKey 即可。