深入掌握JMS（八）：JMSReplyTo

在下面的例子中，首先创建两个Queue，发送者给一个Queue发送，接收者接收到消息之后给另一个Queue回复一个Message，然后再创建一个消费者来接受所回复的消息。

            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.Queue;
            import javax.jms.Session;
            import javax.jms.TextMessage;

            import org.apache.activemq.ActiveMQConnectionFactory;
            import org.apache.activemq.command.ActiveMQQueue;

            public class MessageSendReceiveAndReply {

                public static void main(String[] args) throws Exception {
                    ActiveMQConnectionFactory factory = new
            ActiveMQConnectionFactory("vm://localhost");
                    Connection connection = factory.createConnection();
                    connection.start();
                    //消息发送到这个Queue
                    Queue queue = new ActiveMQQueue("testQueue");

                    //消息回复到这个Queue
                    Queue replyQueue = new ActiveMQQueue("replyQueue");
                    final Session session = connection.createSession(false,
            Session.AUTO_ACKNOWLEDGE);

                    //创建一个消息，并设置它的JMSReplyTo为replyQueue。
                    Message message = session.createTextMessage("Andy");
                    message.setJMSReplyTo(replyQueue);
                    MessageProducer producer = session.createProducer(queue);
                    producer.send(message);
                    //消息的接收者
                    MessageConsumer comsumer = session.createConsumer(queue);
                    comsumer.setMessageListener(new MessageListener(){
                        public void onMessage(Message m) {
                            try {
                                //创建一个新的MessageProducer来发送一个回复消息。
                                MessageProducer producer =
            session.createProducer(m.getJMSReplyTo());
                                producer.send(session.createTextMessage("Hello "
            + ((TextMessage) m).getText()));
                            } catch (JMSException e1) {
                                e1.printStackTrace();
                            }
                        }
                    });
                    //这个接收者用来接收回复的消息
                    MessageConsumer comsumer2 =
            session.createConsumer(replyQueue);
                    comsumer2.setMessageListener(new MessageListener(){
                        public void onMessage(Message m) {
                            try {
                                System.out.println(((TextMessage) m).getText());
                            } catch (JMSException e) {
                                e.printStackTrace();
                            }
                        }
                    });
                }

            }

                首先消息生产者发送一个消息，内容为“Andy”，
            然后消费者收到这个消息之后根据消息的JMSReplyTo，回复一个消息，内容为“Hello Andy'。
            最后在回复的Queue上创建一个接收回复消息的消费者，它输出所回复的内容。

                运行上面的程序，可以得到下面的输出结果：

            Hello Andy