In simple terms the ActiveMQ (three) - ActiveMQ simple HelloWorld example

First post (a) -JMS basic concepts in simple terms ActiveMQ , we introduced two JMS messaging models: point to point and publish-subscribe model, as well as two way messages are consumed: synchronous and asynchronous, JMS programming model of the object, and finally said the advantages of JMS.

The second Bowen layman ActiveMQ (two) -ActiveMQ a brief introduction and installation , we introduced the messaging middleware ActiveMQ, installation, startup, and advantages and disadvantages.

This blog, we use ActiveMQ message for everyone to realize a peer to peer model. If you know of ad-hoc model of shallow, you can look at the first post of introduction.

JMS did not actually think so tall, after reading this blog, you will know what is simple, direct access to the following topic.

Development environment

We are using ActiveMQ 5.11.1 Release version of Windows, the latest version of the official website is ActiveMQ 5.12.0 Release, you can download yourself, download address .

It should be noted that the development time, you want to apache-activemq-5.11.1-bin.zip after decompression inside activemq-all-5.11.1.jar package added to your classpath, this package contains all the jms api interfaces achieve.

Setup the development environment

The establishment of the project
we just need to create a java project on it, import the jar package, Project screenshots:

Point to point messaging model, only one message producer and message consumer, let's write code.

Write producer


package com.tgb.activemq;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;

import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;
/**
 * 消息的生产者（发送者） 
 * @author liang
 *
 */
public class JMSProducer {

    //默认连接用户名
    private static final String USERNAME = ActiveMQConnection.DEFAULT_USER;
    //默认连接密码
    private static final String PASSWORD = ActiveMQConnection.DEFAULT_PASSWORD;
    //默认连接地址
    private static final String BROKEURL = ActiveMQConnection.DEFAULT_BROKER_URL;
    //发送的消息数量
    private static final int SENDNUM = 10;

    public static void main(String[] args) {
        //连接工厂
        ConnectionFactory connectionFactory;
        //连接
        Connection connection = null;
        //会话 接受或者发送消息的线程
        Session session;
        //消息的目的地
        Destination destination;
        //消息生产者
        MessageProducer messageProducer;
        //实例化连接工厂
        connectionFactory = new ActiveMQConnectionFactory(JMSProducer.USERNAME, JMSProducer.PASSWORD, JMSProducer.BROKEURL);

        try {
            //通过连接工厂获取连接
            connection = connectionFactory.createConnection();
            //启动连接
            connection.start();
            //创建session
            session = connection.createSession(true, Session.AUTO_ACKNOWLEDGE);
            //创建一个名称为HelloWorld的消息队列
            destination = session.createQueue("HelloWorld");
            //创建消息生产者
            messageProducer = session.createProducer(destination);
            //发送消息
            sendMessage(session, messageProducer);

            session.commit();

        } catch (Exception e) {
            e.printStackTrace();
        }finally{
            if(connection != null){
                try {
                    connection.close();
                } catch (JMSException e) {
                    e.printStackTrace();
                }
            }
        }

    }
    /**
     * 发送消息
     * @param session
     * @param messageProducer  消息生产者
     * @throws Exception
     */
    public static void sendMessage(Session session,MessageProducer messageProducer) throws Exception{
        for (int i = 0; i < JMSProducer.SENDNUM; i++) {
            //创建一条文本消息 
            TextMessage message = session.createTextMessage("ActiveMQ 发送消息" +i);
            System.out.println("发送消息：Activemq 发送消息" + i);
            //通过消息生产者发出消息 
            messageProducer.send(message);
        }

    }
}

Write consumer


package com.tgb.activemq;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.MessageConsumer;
import javax.jms.Session;
import javax.jms.TextMessage;

import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;
/**
 * 消息的消费者（接受者）
 * @author liang
 *
 */
public class JMSConsumer {

    private static final String USERNAME = ActiveMQConnection.DEFAULT_USER;//默认连接用户名
    private static final String PASSWORD = ActiveMQConnection.DEFAULT_PASSWORD;//默认连接密码
    private static final String BROKEURL = ActiveMQConnection.DEFAULT_BROKER_URL;//默认连接地址

    public static void main(String[] args) {
        ConnectionFactory connectionFactory;//连接工厂
        Connection connection = null;//连接

        Session session;//会话 接受或者发送消息的线程
        Destination destination;//消息的目的地

        MessageConsumer messageConsumer;//消息的消费者

        //实例化连接工厂
        connectionFactory = new ActiveMQConnectionFactory(JMSConsumer.USERNAME, JMSConsumer.PASSWORD, JMSConsumer.BROKEURL);

        try {
            //通过连接工厂获取连接
            connection = connectionFactory.createConnection();
            //启动连接
            connection.start();
            //创建session
            session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            //创建一个连接HelloWorld的消息队列
            destination = session.createQueue("HelloWorld");
            //创建消息消费者
            messageConsumer = session.createConsumer(destination);

            while (true) {
                TextMessage textMessage = (TextMessage) messageConsumer.receive(100000);
                if(textMessage != null){
                    System.out.println("收到的消息:" + textMessage.getText());
                }else {
                    break;
                }
            }

        } catch (JMSException e) {
            e.printStackTrace();
        }

    }
}

run

First, start ActiveMQ, how to start how to start ActiveMQ, see The second Bowen. In the browser, enter: HTTP: // localhost: 8161 / ADMIN / , then started:
Run sender, eclipse console output, as shown below:

At this point, we look at the ActiveMQ server, Queues as follows:

we can see to create a name for the HelloWorld message queue, the queue has 10 messages are not spending, we can also view Browse through which messages are shown below:

If the message these queues, are deleted, consumers are not spending.
We continue to run at consumers, eclipse console prints the message, as follows:

At this point, we look at the ActiveMQ server, Queues as follows:

we can see the HelloWorld message queue changes, more than 10 messages a person in the queue the message is consumed, click Browse to see, it is already empty.
Click Active Consumers, we can see the details of the consumer:

This concludes our example, you can content yourself more ActiveMQ servers become more familiar with ActiveMQ.

to sum up

We achieved this blog point to point messaging model and a synchronization message is sent, it is not very simple?

The following blog post, we will implement a ActiveMQ and Spring integration instance.