实现功能：一条消息发送给多个消费者

交换机模式：topic

相比于direct匹配模式，匹配routingKey时，topic模式下不仅支持完全匹配，还支持两种特殊的匹配方式

#：可以匹配一个或多个字符

*：可以匹配一个字符

生产者：

package com.example.demo.queue.exchangeToQueue.topic;import java.io.IOException;import java.util.concurrent.TimeoutException;import com.example.demo.utils.ConnectionUtil;import com.rabbitmq.client.Channel;import com.rabbitmq.client.Connection;public class Producer {	private static final String EXCHANGE_NAME = "exchange_topic"; 		public static void main(String[] args) {		Connection connection = null;		Channel channel = null;		try {			// 获取连接			connection = ConnectionUtil.getConnection();			// 创建通道			channel = connection.createChannel();			// 声明交换机			channel.exchangeDeclare(EXCHANGE_NAME, "topic");			String routingKey = "debug";			// 生产者发送的信息			String msg = "routingKey="+routingKey;			System.out.println("send msg : "+msg);			// 发送信息			channel.basicPublish(EXCHANGE_NAME, routingKey, null, msg.getBytes());		} catch (Exception e) {			e.printStackTrace();		} finally {			// 关闭通道			try {				channel.close();			} catch (IOException e) {				e.printStackTrace();			} catch (TimeoutException e) {				e.printStackTrace();			}			// 关闭连接			try {				connection.close();			} catch (IOException e) {				e.printStackTrace();			}		}			}	}

消费者1：

package com.example.demo.queue.exchangeToQueue.topic;import java.io.IOException;import com.example.demo.utils.ConnectionUtil;import com.rabbitmq.client.AMQP.BasicProperties;import com.rabbitmq.client.Channel;import com.rabbitmq.client.Connection;import com.rabbitmq.client.DefaultConsumer;import com.rabbitmq.client.Envelope;public class Consumer01 {	private static final String EXCHANGE_NAME = "exchange_topic"; 		private static final String QUEUE_NAME = "topic_exchange_to_queue_01";		public static void main(String[] args) {		try {			// 获取连接			Connection connection = ConnectionUtil.getConnection();			// 创建通道			final Channel channel = connection.createChannel();			// 声明队列			channel.queueDeclare(QUEUE_NAME, true, false, false, null);			String routingKey = "debug";			// 绑定队列到交换机			channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, routingKey);			// 定义消费者			DefaultConsumer consumer = new DefaultConsumer(channel) {				@Override				public void handleDelivery(String consumerTag, Envelope envelope, BasicProperties properties, byte[] body) throws IOException {					String msg = new String(body,"UTF-8");					System.out.println("[1]:receive msg:"+msg);					System.out.println("[1]:deal msg successful. routingKey="+routingKey);				}							};			// 接收信息			channel.basicConsume(QUEUE_NAME, true, consumer);		} catch (Exception e) {			e.printStackTrace();		}	}	}

消费者2：

package com.example.demo.queue.exchangeToQueue.topic;import java.io.IOException;import com.example.demo.utils.ConnectionUtil;import com.rabbitmq.client.AMQP.BasicProperties;import com.rabbitmq.client.Channel;import com.rabbitmq.client.Connection;import com.rabbitmq.client.DefaultConsumer;import com.rabbitmq.client.Envelope;public class Consumer02 {	private static final String EXCHANGE_NAME = "exchange_topic"; 		private static final String QUEUE_NAME = "topic_exchange_to_queue_02";		public static void main(String[] args) {		try {			// 获取连接			Connection connection = ConnectionUtil.getConnection();			// 创建通道			final Channel channel = connection.createChannel();			// 声明队列			channel.queueDeclare(QUEUE_NAME, true, false, false, null);			String routingKey = "debug.*";			// 绑定队列到交换机			channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, routingKey);			// 定义消费者			DefaultConsumer consumer = new DefaultConsumer(channel) {				@Override				public void handleDelivery(String consumerTag, Envelope envelope, BasicProperties properties, byte[] body) throws IOException {					String msg = new String(body,"UTF-8");					System.out.println("[2]:receive msg:"+msg);					System.out.println("[2]:deal msg successful. routingKey="+routingKey);				}			};			// 接收信息			channel.basicConsume(QUEUE_NAME, true, consumer);		} catch (Exception e) {			e.printStackTrace();		}	}	}

消费者3：

package com.example.demo.queue.exchangeToQueue.topic;import java.io.IOException;import com.example.demo.utils.ConnectionUtil;import com.rabbitmq.client.AMQP.BasicProperties;import com.rabbitmq.client.Channel;import com.rabbitmq.client.Connection;import com.rabbitmq.client.DefaultConsumer;import com.rabbitmq.client.Envelope;public class Consumer03 {	private static final String EXCHANGE_NAME = "exchange_topic"; 		private static final String QUEUE_NAME = "topic_exchange_to_queue_03";		public static void main(String[] args) {		try {			// 获取连接			Connection connection = ConnectionUtil.getConnection();			// 创建通道			final Channel channel = connection.createChannel();			// 声明队列			channel.queueDeclare(QUEUE_NAME, true, false, false, null);			String routingKey = "debug.#";			// 绑定队列到交换机			channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, routingKey);			// 定义消费者			DefaultConsumer consumer = new DefaultConsumer(channel) {				@Override				public void handleDelivery(String consumerTag, Envelope envelope, BasicProperties properties, byte[] body) throws IOException {					String msg = new String(body,"UTF-8");					System.out.println("[3]:receive msg:"+msg);					System.out.println("[3]:deal msg successful. routingKey="+routingKey);				}			};			// 接收信息			channel.basicConsume(QUEUE_NAME, true, consumer);		} catch (Exception e) {			e.printStackTrace();		}	}	}

和之前一样，涉及到了交换机，而在消费者类中中并没有声明交换机，所以需要先执行生产者类的main方法

接下来，我们就可以依次执行三个消费者类的main方法，之后再执行生产者类的main方法。

生产者指定的routingKey为【debug】，而消费者指定的routingKey依次为【debug】【debug.*】【debug.#】，理论上应该只有消费者1才能收到消息。下面来展示结果：

消费者1终端：

消费者2终端：

消费者3终端：

我也看不懂了，消费者3怎么也收到了消息，晕那。。。。。。。。