实战Topic

与Queue不同的是，Topic实现的是发布/订阅模型，在下面的例子中，启动2个消费者共同监听一个Topic，然后循环给这个Topic中发送多个消息。

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.JMSException;
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 org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.activemq.command.ActiveMQTopic;

public class TopicTest {

/**
* @param args
* @throws JMSException
*/
public static void main(String[] args) throws JMSException {
// TODO Auto-generated method stub
// ConnectionFactory ：连接工厂，JMS 用它创建连接
ConnectionFactory factory = new ActiveMQConnectionFactory(ActiveMQConnection.DEFAULT_USER
, ActiveMQConnection.DEFAULT_PASSWORD, "tcp://127.0.0.1:61616");
//JMS 客户端到JMS Provider 的连接
Connection connection = factory.createConnection();
connection.start();
// Session： 一个发送或接收消息的线程
Session session = connection.createSession(Boolean.FALSE, Session.AUTO_ACKNOWLEDGE);
// Destination ：消息的目的地;消息发送给谁.   
// 获取session注意参数值my-queue是Query的名字
Topic topic = new ActiveMQTopic("topicTest");

MessageConsumer comsumer1 = session.createConsumer(topic);
comsumer1.setMessageListener(new MessageListener() {

public void onMessage(Message message) {
// TODO Auto-generated method stub
try {
System.out.println("Consumer 1 get " + ((TextMessage)message).getText());
} catch (Exception e) {
e.printStackTrace();
}
}
});


MessageConsumer comsumer2 = session.createConsumer(topic);
comsumer2.setMessageListener(new MessageListener() {

public void onMessage(Message message) {
// TODO Auto-generated method stub
try {
System.out.println("Consumer 2 get " + ((TextMessage)message).getText());
} catch (Exception e) {
e.printStackTrace();
}
}
});

MessageProducer producer = session.createProducer(topic);
for (int i=0; i<10; i++) {
producer.send(session.createTextMessage("Message：" + i));
}

}
}


运行后得到下面的输出结果：
Consumer 1 get Message：0
Consumer 2 get Message：0
Consumer 1 get Message：1
Consumer 2 get Message：1
Consumer 1 get Message：2
Consumer 2 get Message：2
Consumer 1 get Message：3
Consumer 2 get Message：3
Consumer 1 get Message：4
Consumer 2 get Message：4
Consumer 1 get Message：5
Consumer 2 get Message：5
Consumer 1 get Message：6
Consumer 2 get Message：6
Consumer 1 get Message：7
Consumer 2 get Message：7
Consumer 1 get Message：8
Consumer 2 get Message：8
Consumer 1 get Message：9
Consumer 2 get Message：9


说明每一个消息都会被所有的消费者消费。