【RabbitMQ】路由模式和通配符模式的具体实现

路由模式

队列和交换机的绑定，不能是任意的绑定了，而是要指定一个 BindingKey (RoutingKey 的一种) 消息的发送方在向 Exchange 发送消息时，也需要指定消息的 RoutingKey

Exchange 也不再把消息交给每一个绑定的 key，而是根据消息的 RoutingKey 进行判断，只有队列绑定时的 BindingKey 和发送消息的 RoutingKey 完全一致，才会接收到消息

• 课程中所谓的 BindingKey，是 RoutingKey 的一种
• 早期也叫做 routingKey，只是在最新的文档中被改成 BindingKey 了

我们通常：

• 把消息发送称为：Routingkey
• 把队列绑定称为：BindingKey

创建队列和交换机

在 Constants 中添加：

// 路由模式  
public static final String DIRECT_EXCHANGE = "direct.exchange";  
public static final String DIRECT_QUEUE1 = "direct.queue1";  
public static final String DIRECT_QUEUE2 = "direct.queue2";

生产者代码

和发布订阅模式的区别是：交换机类型不同，绑定队列的 BindingKey 不同

创建交换机

创建交换机，定义交换机类型为 BuiltinExchangeType.DIRECT

channel.exchangeDeclare(Constants.DIRECT_EXCHANGE, BuiltinExchangeType.DIRECT, true);

• BuiltinExchangeType 一共有四种
  1. DIRECT("direct")
  2. FANOUT("fanout")
  3. TOPIC("topic")
  4. HEADERS("headers")

声明队列

channel.queueDeclare(Constants.DIRECT_QUEUE1, true, false, false, null);  
channel.queueDeclare(Constants.DIRECT_QUEUE2, true, false, false, null);

绑定交换机和队列

// 队列1绑定 a
channel.queueBind(Constants.DIRECT_QUEUE1, Constants.DIRECT_EXCHANGE, "a");  
// 队列2 绑定 a, b, c
channel.queueBind(Constants.DIRECT_QUEUE2, Constants.DIRECT_EXCHANGE, "a");  
channel.queueBind(Constants.DIRECT_QUEUE2, Constants.DIRECT_EXCHANGE, "b");  
channel.queueBind(Constants.DIRECT_QUEUE2, Constants.DIRECT_EXCHANGE, "c");

发送消息

String msg_a = "hello direct, my routingKey is a...";  
channel.basicPublish(Constants.DIRECT_EXCHANGE, "a", null, msg_a.getBytes());  String msg_b = "hello direct, my routingKey is b...";  
channel.basicPublish(Constants.DIRECT_EXCHANGE, "b", null, msg_b.getBytes());  String msg_c = "hello direct, my routingKey is c...";  
channel.basicPublish(Constants.DIRECT_EXCHANGE, "c", null, msg_c.getBytes());

• 发送消息时，指定 RoutingKey

完整代码

package rabbitmq.routing;  import com.rabbitmq.client.BuiltinExchangeType;  
import com.rabbitmq.client.Channel;  
import com.rabbitmq.client.Connection;  
import com.rabbitmq.client.ConnectionFactory;  
import rabbitmq.constant.Constants;  import java.io.IOException;  
import java.util.concurrent.TimeoutException;  
import java.util.function.BinaryOperator;  public class Producer {  public static void main(String[] args) throws IOException, TimeoutException {  // 1. 建立连接  ConnectionFactory connectionFactory = new ConnectionFactory();  connectionFactory.setHost(Constants.HOST);  connectionFactory.setPort(Constants.PORT);  connectionFactory.setUsername(Constants.USER_NAME);  connectionFactory.setPassword(Constants.PASSWORD);  connectionFactory.setVirtualHost(Constants.VIRTUAL_HOST);  Connection connection = connectionFactory.newConnection();  // 2. 开启信道  Channel channel = connection.createChannel();  // 3. 声明交换机  channel.exchangeDeclare(Constants.DIRECT_EXCHANGE, BuiltinExchangeType.DIRECT, true);  // 4. 声明队列  channel.queueDeclare(Constants.DIRECT_QUEUE1, true, false, false, null);  channel.queueDeclare(Constants.DIRECT_QUEUE2, true, false, false, null);  // 5. 绑定交换机和队列  channel.queueBind(Constants.DIRECT_QUEUE1, Constants.DIRECT_EXCHANGE, "a");  channel.queueBind(Constants.DIRECT_QUEUE2, Constants.DIRECT_EXCHANGE, "a");  channel.queueBind(Constants.DIRECT_QUEUE2, Constants.DIRECT_EXCHANGE, "b");  channel.queueBind(Constants.DIRECT_QUEUE2, Constants.DIRECT_EXCHANGE, "c");  // 6. 发送消息  String msg_a = "hello direct, my routingKey is a...";  channel.basicPublish(Constants.DIRECT_EXCHANGE, "a", null, msg_a.getBytes());  String msg_b = "hello direct, my routingKey is b...";  channel.basicPublish(Constants.DIRECT_EXCHANGE, "b", null, msg_b.getBytes());  String msg_c = "hello direct, my routingKey is c...";  channel.basicPublish(Constants.DIRECT_EXCHANGE, "c", null, msg_c.getBytes());  System.out.println("消息发送成功！");  // 7. 释放资源  channel.close();  connection.close();  }  
}

消费者代码

Routing 模式的消费者代码和 Publish/Subscribe 代码一样，同样复制出来两份

• Consumer1
• Consumer2

package rabbitmq.routing;  import com.rabbitmq.client.*;  
import rabbitmq.constant.Constants;  import java.io.IOException;  
import java.util.concurrent.TimeoutException;  public class Consumer1 {  public static void main(String[] args) throws IOException, TimeoutException {  //1. 建立连接  ConnectionFactory connectionFactory = new ConnectionFactory();  connectionFactory.setHost(Constants.HOST);  connectionFactory.setPort(Constants.PORT);  connectionFactory.setUsername(Constants.USER_NAME);  connectionFactory.setPassword(Constants.PASSWORD);  connectionFactory.setVirtualHost(Constants.VIRTUAL_HOST);  Connection connection = connectionFactory.newConnection();  //2. 建立信道  Channel channel = connection.createChannel();  //3. 声明队列  channel.queueDeclare(Constants.DIRECT_QUEUE1, true, false, false, null);  //4. 消费信息  DefaultConsumer consumer = new DefaultConsumer(channel){  @Override  public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {  System.out.println("接收到消息：" + new String(body));  }  };  channel.basicConsume(Constants.DIRECT_QUEUE1, true, consumer);  }  
}

运行程序

启动生产者

1. 消息路由

• 可以看到 direct.queue1 队列中，路由了一条消息
• 可以看到 direct.queue2 队列中，路由了两条消息

2. 队列和交换机的绑定
   

启动消费者

Consumer1：

接收到消息：hello direct, my routingKey is a...

Consumer2：

接收到消息：hello direct, my routingKey is a...
接收到消息：hello direct, my routingKey is b...
接收到消息：hello direct, my routingKey is c...

通配符模式

Topics 和 Routing 模式的区别是：

1. Topics 模式使用的交换机类型是 topic（Routing 模式用的交换机类型为 direct）
2. topic 类型的交换机在匹配规则上进行了扩展，Binding Key 支持通配符匹配（direct 类型的交换机路由规则是 BindingKey 和 RoutingKey 完全匹配）

在 Topic 类型的交换机在匹配规则上，有一些要求：

1. RoutingKey 是由一系列由点(.) 分隔的单词，比如“stock.sd.nyse”, “nyse.vmw”, “quick.orange.rabbit”
2. BindingKey 和 RoutingKey 一样，也是点(.) 分割的字符串
3. BindingKey 中可以存在两种特殊的字符串，用于模糊匹配
   • * 表示一个单词
   • # 表示多个单词(0-N个)

比如：

• Binding Key 为“d.a.b”会同时路由到 Q1 和 Q2
• Binding Key 为“d.a.f”会路由到 Q1
• Binding Key 为“c.e.f”会路由到 Q2
• Binding Key 为“d.b.f”会被丢弃，或者返回给生产者(需要设置 mandatory)

创建队列和交换机

public static final String TOPIC_EXCHANGE = "topic.exchange";  
public static final String TOPIC_QUEUE1 = "topic.queue1";  
public static final String TOPIC_QUEUE2 = "topic.queue2";

生产者代码

和路由模式，发布订阅模式的区别是：交换机类型不同，绑定队列的 RoutingKey 不同

创建交换机

定义交换机类型为 BuiltinExchangeType.TOPIC

channel.exchangeDeclare(Constants.TOPIC_EXCHANGE, BuiltinExchangeType.TOPIC, true);

声明队列

channel.queueDeclare(Constants.TOPIC_QUEUE1, true, false, false, null);  
channel.queueDeclare(Constants.TOPIC_QUEUE2, true, false, false, null);

绑定交换机和队列

channel.queueBind(Constants.TOPIC_QUEUE1, Constants.TOPIC_EXCHANGE, "*.a.*");  
channel.queueBind(Constants.TOPIC_QUEUE2, Constants.TOPIC_EXCHANGE, "*.*.b");  
channel.queueBind(Constants.TOPIC_QUEUE2, Constants.TOPIC_EXCHANGE, "c.#");

发送消息

String msg_a = "hello topic, my routingkey is ae.a.f...";  
channel.basicPublish(Constants.TOPIC_EXCHANGE, "ae.a.f", null, msg_a.getBytes()); // 转发到 Q1  String msg_b = "hello topic, my routingkey is ef.a.b...";  
channel.basicPublish(Constants.TOPIC_EXCHANGE, "ef.a.b", null, msg_b.getBytes()); // 转发到 Q1 和 Q2  String msg_c = "hello topic, my routingkey is c.ef.d...";  
channel.basicPublish(Constants.TOPIC_EXCHANGE, "c.ef.d", null, msg_c.getBytes()); // 转发到 Q2

完整代码

package rabbitmq.topic;  import com.rabbitmq.client.BuiltinExchangeType;  
import com.rabbitmq.client.Channel;  
import com.rabbitmq.client.Connection;  
import com.rabbitmq.client.ConnectionFactory;  
import rabbitmq.constant.Constants;  import java.io.IOException;  
import java.util.concurrent.TimeoutException;  public class Producer {  public static void main(String[] args) throws IOException, TimeoutException {  //1. 建立连接  ConnectionFactory connectionFactory = new ConnectionFactory();  connectionFactory.setHost(Constants.HOST);  connectionFactory.setPort(Constants.PORT);  connectionFactory.setUsername(Constants.USER_NAME);  connectionFactory.setPassword(Constants.PASSWORD);  connectionFactory.setVirtualHost(Constants.VIRTUAL_HOST);  Connection connection = connectionFactory.newConnection();  //2. 开启信道  Channel channel = connection.createChannel();  //3.声明交换机  channel.exchangeDeclare(Constants.TOPIC_EXCHANGE, BuiltinExchangeType.TOPIC, true);  //4. 声明队列  channel.queueDeclare(Constants.TOPIC_QUEUE1, true, false, false, null);  channel.queueDeclare(Constants.TOPIC_QUEUE2, true, false, false, null);  //5. 绑定交换机和队列  channel.queueBind(Constants.TOPIC_QUEUE1, Constants.TOPIC_EXCHANGE, "*.a.*");  channel.queueBind(Constants.TOPIC_QUEUE2, Constants.TOPIC_EXCHANGE, "*.*.b");  channel.queueBind(Constants.TOPIC_QUEUE2, Constants.TOPIC_EXCHANGE, "c.#");  //6. 发送消息  String msg_a = "hello topic, my routingkey is ae.a.f...";  channel.basicPublish(Constants.TOPIC_EXCHANGE, "ae.a.f", null, msg_a.getBytes()); // 转发到 Q1  String msg_b = "hello topic, my routingkey is ef.a.b...";  channel.basicPublish(Constants.TOPIC_EXCHANGE, "ef.a.b", null, msg_b.getBytes()); // 转发到 Q1 和 Q2  String msg_c = "hello topic, my routingkey is c.ef.d...";  channel.basicPublish(Constants.TOPIC_EXCHANGE, "c.ef.d", null, msg_c.getBytes()); // 转发到 Q2  System.out.println("消息发送成功");  //7. 释放资源  channel.close();  connection.close();  }  
}

消费者代码

消费者代码和 Routing 模式的一样，只要修改消费队列的名称即可

• 消费者 1
• 消费者 2

package rabbitmq.topic;  import com.rabbitmq.client.*;  
import rabbitmq.constant.Constants;  import java.io.IOException;  
import java.util.concurrent.TimeoutException;  public class Consumer2 {  public static void main(String[] args) throws IOException, TimeoutException {  //1. 建立连接  ConnectionFactory connectionFactory = new ConnectionFactory();  connectionFactory.setHost(Constants.HOST);  connectionFactory.setPort(Constants.PORT);  connectionFactory.setUsername(Constants.USER_NAME);  connectionFactory.setPassword(Constants.PASSWORD);  connectionFactory.setVirtualHost(Constants.VIRTUAL_HOST);  Connection connection = connectionFactory.newConnection();  //2. 开启信道  Channel channel = connection.createChannel();  //3. 声明队列  channel.queueDeclare(Constants.TOPIC_QUEUE2, true, false, false, null);  //4. 消费消息  DefaultConsumer consumer = new DefaultConsumer(channel) {  @Override  public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {  System.out.println("接收到消息：" + new String(body));  }  };  channel.basicConsume(Constants.TOPIC_QUEUE2, true, consumer);  }  
}

运行程序

启动生产者

• 可以看到队列的消息数

启动消费者

1. Consumer1

接收到消息：hello topic, my routingkey is ae.a.f...
接收到消息：hello topic, my routingkey is ef.a.b...

2. Consumer2

接收到消息：hello topic, my routingkey is ef.a.b...
接收到消息：hello topic, my routingkey is c.ef.d...