Java使用RabbitMQ之订阅分发（Topic）
使用RabbitMQ进行消息发布和订阅，生产者将消息发送给转发器（exchange），转发器根据路由键匹配已绑定的消息队列并转发消息，主题模式支持路由键的通配。
生产者代码：
1 package org.study.exchange3.topic3; 2 3 import com.rabbitmq.client.Channel; 4 import com.rabbitmq.client.Connection; 5 import org.junit.Test; 6 import org.study.utils.ConnectionUtils; 7 8 import java.io.IOException; 9 import java.util.concurrent.TimeoutException; 10 11 /** 12 * topic-主题模式（分发订阅） 13 * exchange只转发消息，但是没有存储能力，只有队列才有存储能力 14 * 主题模式支持路由键的通配符 15 * “#”表示0个或若干个关键字，“*”表示一个关键字。 16 */ 17 public class Sender { 18 public static final String QUEUE_NAME = "test_topic_queue"; 19 public static final String EXCHANGE_NAME = "topic_exchange"; 20 21 @Test 22 public void send() throws IOException, TimeoutException, InterruptedException { 23 // 获取连接 24 Connection conn = ConnectionUtils.getConnection(); 25 // 获取通道 26 Channel channel = conn.createChannel(); 27 // //创建队列 28 // channel.queueDeclare(QUEUE_NAME, false, false, false, null); 29 //声明转发器 30 channel.exchangeDeclare(EXCHANGE_NAME, "topic"); 31 //每个消费者发送确认消息前，只发送一条消息 32 channel.basicQos(1); 33 34 String msg = "hello rabbitmq topic !"; 35 //发送消息至转发器,指定路由键 36 channel.basicPublish(EXCHANGE_NAME, "key.key", null, msg.getBytes()); 37 System.out.println("[send] msg " + msg); 38 39 channel.close(); 40 conn.close(); 41 } 42 }
消费者代码：
1 package org.study.exchange3.topic3; 2 3 import com.rabbitmq.client.*; 4 import org.junit.Test; 5 import org.study.utils.ConnectionUtils; 6 7 import java.io.IOException; 8 import java.util.concurrent.TimeoutException; 9 10 /** 11 * 主题模式-接收消息 12 */ 13 public class Recv { 14 public static final String QUEUE_NAME = "test_topic_queue"; 15 public static final String EXCHANGE_NAME = "topic_exchange"; 16 17 @Test 18 public void recv() throws IOException, TimeoutException, InterruptedException { 19 Connection conn = ConnectionUtils.getConnection(); 20 Channel channel = conn.createChannel(); 21 channel.queueDeclare(QUEUE_NAME, false, false, false, null); 22 channel.basicQos(1); 23 /* 24 * 队列绑定转发器,路由键通配符#和* 25 * #：表示0个或多个字符 26 * *：表示一个字符 27 * */ 28 channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key.#"); 29 30 //定义消费者 31 DefaultConsumer consumer = new DefaultConsumer(channel) { 32 //重写获取到达消息 33 @Override 34 public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException { 35 String msg = new String(body, "utf-8"); 36 System.out.println("[1] recv: " + msg); 37 38 try { 39 Thread.sleep(100); 40 } catch (InterruptedException e) { 41 e.printStackTrace(); 42 } finally { 43 System.out.println("[1] done!"); 44 // 回执 45 channel.basicAck(envelope.getDeliveryTag(), false); 46 } 47 } 48 }; 49 50 while (true) { 51 //监听队列 52 channel.basicConsume(QUEUE_NAME, false, consumer); 53 Thread.sleep(1000); 54 } 55 56 } 57 }
