ACTIVEMQ-发布者订阅者hello world示例 [英] ACTIVEMQ- publisher subscriber hello world example

问题描述

有两个程序：订阅者和发布者...
订阅者能够将消息放到主题上并且消息发送成功。
当我在浏览器上检查activemq服务器时，它显示1 msg排队。但是当我运行消费者代码时，它没有收到消息

There are two programs: subscriber and publisher... Subscriber is able to put the message onto the topic and the message is sent successfully. When I check the activemq server on my browser it shows 1 msg enqueued . But when I run the consumer code, it is not receiving the message

这是生产者代码：

import javax.jms.*;

import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;

public class producer {

    private static String url = ActiveMQConnection.DEFAULT_BROKER_URL;

    public static void main(String[] args) throws JMSException {

        ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(url);
        Connection connection = connectionFactory.createConnection();
        connection.start();

        // JMS messages are sent and received using a Session. We will
        // create here a non-transactional session object. If you want
        // to use transactions you should set the first parameter to 'true'
        Session session = connection.createSession(false,
                Session.AUTO_ACKNOWLEDGE);

        Topic topic = session.createTopic("testt");

        MessageProducer producer = session.createProducer(topic);

        // We will send a small text message saying 'Hello'

        TextMessage message = session.createTextMessage();

        message.setText("HELLO JMS WORLD");
        // Here we are sending the message!
        producer.send(message);
        System.out.println("Sent message '" + message.getText() + "'");

        connection.close();
    }
}

运行此代码后，控制台的输出为：

After I run this code the output at the console is:

26 Jan, 2012 2:30:04 PM org.apache.activemq.transport.failover.FailoverTransport doReconnect
INFO: Successfully connected to tcp://localhost:61616
Sent message 'HELLO JMS WORLD'

以下是消费者代码：

import javax.jms.*;

import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;

public class consumer {
    // URL of the JMS server
    private static String url = ActiveMQConnection.DEFAULT_BROKER_URL;

    // Name of the topic from which we will receive messages from = " testt"

    public static void main(String[] args) throws JMSException {
        // Getting JMS connection from the server

        ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(url);
        Connection connection = connectionFactory.createConnection();
        connection.start();

        Session session = connection.createSession(false,
                Session.AUTO_ACKNOWLEDGE);

        Topic topic = session.createTopic("testt");

        MessageConsumer consumer = session.createConsumer(topic);

        MessageListener listner = new MessageListener() {
            public void onMessage(Message message) {
                try {
                    if (message instanceof TextMessage) {
                        TextMessage textMessage = (TextMessage) message;
                        System.out.println("Received message"
                                + textMessage.getText() + "'");
                    }
                } catch (JMSException e) {
                    System.out.println("Caught:" + e);
                    e.printStackTrace();
                }
            }
        };

        consumer.setMessageListener(listner);
        connection.close();

    }
}    

运行此代码后，它不会什么都有。
有人可以帮我解决这个问题吗？

After I run this code it doesnt show anything. Can someone help to me to overcome this problem?

推荐答案

你的问题是你的消费者正在运行然后关闭立即降价。

Your issue is that your consumer is running and then shutting down immediately.

尝试将此添加到您的消费者中：

Try adding this into your consumer:

    consumer.setMessageListener(listner);

    try {
        System.in.read();
    } catch (IOException e) {
        e.printStackTrace();
    }

    connection.close();

这将等到你在停止前点击一个键。

This will wait until you hit a key before stopping.

其他需要考虑的事项：

• 使用finally块进行收盘


• Java命名约定鼓励在类的第一个字母处使用大写字母

这篇关于ACTIVEMQ-发布者订阅者hello world示例的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！