ActiveMQ发布订阅模式

Topic主题发布和订阅消息

前面讲的案例都是点对点的消息，即一个生产者发送的一条消息只能被一个消费者消费，然后就移除了。

而topic模式一条消息可以被多个消费者订阅，关系如下:

定义生产者

package com.dpb.topic;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.DeliveryMode;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.MapMessage;
import javax.jms.Message;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.Topic;
import javax.jms.TopicConnection;
import javax.jms.TopicConnectionFactory;
import javax.jms.TopicPublisher;
import javax.jms.TopicSession;

import org.apache.activemq.ActiveMQConnectionFactory;

/**
 * ActiveMQ中的生产者(Producer)
 * @author dengp
 *
 */
public class MyProducer {

  public void sendhello2ActiveMq(String messageText) {
    TopicSession session = null;
    TopicConnection conn = null;
    try {
      TopicConnectionFactory factory = new ActiveMQConnectionFactory("admin", "admin", "tcp://192.168.88.121:61616");
      conn = factory.createTopicConnection();
      conn.start();
      session = conn.createTopicSession(false, Session.AUTO_ACKNOWLEDGE);
      // 创建消息队列
      Topic topic = session.createTopic("test-topic");
      // 创建消息发送者
      TopicPublisher publisher = session.createPublisher(topic);
      // 设置持久化模式 NON_PERSISTENT不开启  PERSISTENT 开启 默认是开启
      publisher.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
      MapMessage mapMessage = session.createMapMessage();
      mapMessage.setString("name", "波波烤鸭");
      mapMessage.setString("address", "深圳");
      publisher.send(mapMessage);
      
      // 提交会话
      session.commit();
    } catch (Exception e) {
      e.printStackTrace();
      System.out.println("访问ActiveMQ服务发生错误!!");
    } finally {
      
      try {
        // 回收会话资源
        if (null != session)
          session.close();
      } catch (JMSException e) {
        e.printStackTrace();
      }
      try {
        // 回收链接资源
        if (null != conn)
          conn.close();
      } catch (JMSException e) {
        e.printStackTrace();
      }
    }
  }
}

定义消费者

package com.dpb.topic;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.DeliveryMode;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.MapMessage;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.jms.Topic;
import javax.jms.TopicConnection;
import javax.jms.TopicConnectionFactory;
import javax.jms.TopicPublisher;
import javax.jms.TopicSession;

import org.apache.activemq.ActiveMQConnectionFactory;

/**
 * ActiveMQ中的消费者(Consumer)
 * @author dengp
 *
 */
public class MyConsumer {

  public void reciveHelloFormActiveMq() {
      TopicSession session = null;
      TopicConnection conn = null;
      try {
        TopicConnectionFactory factory = new ActiveMQConnectionFactory("admin", "admin", "tcp://192.168.88.121:61616");
        conn = factory.createTopicConnection();
        conn.start();
        session = conn.createTopicSession(false, Session.AUTO_ACKNOWLEDGE);
        // 创建消息队列
        Topic topic = session.createTopic("test-topic");
        // 创建消息接受者
        MessageConsumer consumer = session.createConsumer(topic);
        consumer.setMessageListener(new MessageListener() {
          
          @Override
          public void onMessage(Message msg) {
            if (msg != null) {
                          MapMessage map = (MapMessage) msg;
                          try {
                             System.out.println(map.getString("name") + "接收#" + map.getString("address"));
                          } catch (JMSException e) {
                              e.printStackTrace();
                          }
                      }
          }
        });
         // 休眠100s再关闭
              Thread.sleep(1000 * 100); 
        // 提交会话
        session.commit();
      } catch (Exception e) {
        e.printStackTrace();
        System.out.println("访问ActiveMQ服务发生错误!!");
      } finally {
        try {
          // 回收会话资源
          if (null != session)
            session.close();
        } catch (JMSException e) {
          e.printStackTrace();
        }
        try {
          // 回收链接资源
          if (null != conn)
            conn.close();
        } catch (JMSException e) {
          e.printStackTrace();
        }
      }
  }
}

测试

先启动消费者，可以开启多个

public static void main(String[] args) {
  MyConsumer con = new MyConsumer();
  con.reciveHelloFormActiveMq();
}

启动生产者

public static void main(String[] args) {
  MyProducer pro = new MyProducer();
  pro.sendhello2ActiveMq("你好啊...topic");
}

好了本文介绍到此，下篇介绍ActiveMQ和Spring的整合