與Queue不同的是,Topic實現的是發佈/訂閱模型,在下面的例子中,啓動2個消費者共同監聽一個Topic,然後循環給這個Topic中發送多個消息。
- import javax.jms.Connection;
- 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.ActiveMQConnectionFactory;
- import org.apache.activemq.command.ActiveMQTopic;
- public class TopicTest {
- public static void main(String[] args) throws Exception {
- ActiveMQConnectionFactory factory = new ActiveMQConnectionFactory("vm://localhost");
- Connection connection = factory.createConnection();
- connection.start();
- //創建一個Topic
- Topic topic= new ActiveMQTopic("testTopic");
- Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
- //註冊消費者1
- MessageConsumer consumer1 = session.createConsumer(topic);
- consumer1.setMessageListener(new MessageListener(){
- public void onMessage(Message m) {
- try {
- System.out.println("Consumer1 get " + ((TextMessage)m).getText());
- } catch (JMSException e) {
- e.printStackTrace();
- }
- }
- });
- //註冊消費者2
- MessageConsumer consumer2 = session.createConsumer(topic);
- consumer2.setMessageListener(new MessageListener(){
- public void onMessage(Message m) {
- try {
- System.out.println("Consumer2 get " + ((TextMessage)m).getText());
- } catch (JMSException e) {
- e.printStackTrace();
- }
- }
- });
- //創建一個生產者,然後發送多個消息。
- MessageProducer producer = session.createProducer(topic);
- for(int i=0; i<10; i++){
- producer.send(session.createTextMessage("Message:" + i));
- }
- }
- }
運行後得到下面的輸出結果:
Consumer1 get Message:0
Consumer2 get Message:0
Consumer1 get Message:1
Consumer2 get Message:1
Consumer1 get Message:2
Consumer2 get Message:2
Consumer1 get Message:3
Consumer2 get Message:3
Consumer1 get Message:4
Consumer2 get Message:4
Consumer1 get Message:5
Consumer2 get Message:5
Consumer1 get Message:6
Consumer2 get Message:6
Consumer1 get Message:7
Consumer2 get Message:7
Consumer1 get Message:8
Consumer2 get Message:8
Consumer1 get Message:9
Consumer2 get Message:9
說明每一個消息都會被所有的消費者消費。
轉載自:http://blog.csdn.net/iamfafa/article/details/6264698