JMS学习六（ActiveMQ Topic之持久订阅）

最新推荐文章于 2024-03-13 17:44:07 发布

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最新推荐文章于 2024-03-13 17:44:07 发布

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分类专栏： JMS

本文链接：https://blog.youkuaiyun.com/QH_JAVA/article/details/60957401

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13 篇文章

订阅专栏

上篇文章中Topic（主题）传送模型可以有两种订阅模式即持久订阅和非持久订阅，废话少说看代码：

一、非持久订阅

1、消息生产者

package mqtest2;

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

import org.apache.activemq.ActiveMQConnectionFactory;

public class Producer3 {
	public static void main(String[] args) throws Exception {
		// 创建一个JMS connection factory
		ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(
				"admin", "admin", "tcp://127.0.0.1:61616");
		// 通过connection factory来创建JMS connection
		Connection connection = connectionFactory.createConnection();
		// 启动JMS connection
		connection.start();
		// 通过connection创建JMS session
		Session session = connection.createSession(Boolean.FALSE,
				Session.AUTO_ACKNOWLEDGE);
		// 创建JMS destination
		Destination destination = session.createTopic("topic-test3");
		// 创建JMS producer
		MessageProducer producer = session.createProducer(destination);
		producer.setDeliveryMode(DeliveryMode.PERSISTENT);
		for (int i = 0; i < 5; i++) {
			TextMessage message = session.createTextMessage("message: " + i);
			// 发送message
			producer.send(message);
		}
		// 关闭所有的JMS资源
		session.close();
		connection.close();
	}

}

2、消息消费者

package mqtest2;

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.Session;
import javax.jms.TextMessage;
import javax.jms.Topic;
import org.apache.activemq.ActiveMQConnectionFactory;

public class Receive3 {
	public static void main(String[] args) throws Exception {
		// 创建一个JMS connection factory
		ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(
				"admin", "admin", "tcp://127.0.0.1:61616");
		// 通过connection factory来创建JMS connection
		Connection connection = connectionFactory.createConnection();
		// 启动JMS connection
		connection.start();
		// 通过connection创建JMS session
		Session session = connection.createSession(Boolean.FALSE,
				Session.AUTO_ACKNOWLEDGE);
		// 创建JMS destination
		Topic destination = session.createTopic("topic-test3");
		// 创建JMS consumer
		MessageConsumer consumer = session.createConsumer(destination);
		// 设置监听
		consumer.setMessageListener(new MessageListener() {
			public void onMessage(Message message) {
				message = (TextMessage) message;
				try {
					String value = ((TextMessage) message).getText();
					System.out.println("value2: " + value);
				} catch (JMSException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		});
	}
}

这个非持久的订阅是不是和第二篇中的一样啊，是的都是一样的。

二、持久订阅

持久订阅的前提是要发送持久化消息，将消息持久化到磁盘，一边之后再读取。

1、消息生产者

package mqtest2;

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

import org.apache.activemq.ActiveMQConnectionFactory;
public class Producter {
	public static void main(String[] args) throws Exception {
        //创建一个JMS connection factory
        ConnectionFactory connectionFactory = new ActiveMQConnectionFactory("admin","admin","tcp://127.0.0.1:61616");
        //通过connection factory来创建JMS connection
        Connection connection = connectionFactory.createConnection();
        //通过connection创建JMS session
        Session session = connection.createSession(Boolean.FALSE, Session.AUTO_ACKNOWLEDGE);
        //创建JMS destination
        Destination destination = session.createTopic("PersistenceTopic");
        //创建JMS producer
        MessageProducer producer = session.createProducer(destination);
        producer.setDeliveryMode(DeliveryMode.PERSISTENT);
        //启动JMS connection
        connection.start();
        for(int i = 0;i < 5;i++){
            TextMessage message = session.createTextMessage("message"+i);
            //发送message
            producer.send(message);
        }
        //关闭所有的JMS资源
        session.close();
        connection.close();
    }
	
}

2、消息消费者

package mqtest2;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.jms.Topic;
import javax.jms.TopicSubscriber;

import org.apache.activemq.ActiveMQConnectionFactory;

public class Receive1 {
	public static void main(String[] args) throws Exception {
		// 创建一个JMS connection factory
		ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(
				"admin", "admin", "tcp://127.0.0.1:61616");
		// 通过connection factory来创建JMS connection
		Connection connection = connectionFactory.createConnection();
		// 设置一个标记id
		connection.setClientID("TT");
		// 启动JMS connection
		connection.start();
		// 通过connection创建JMS session
		Session session = connection.createSession(Boolean.FALSE,
				Session.AUTO_ACKNOWLEDGE);
		// 创建JMS destination
		Topic destination = session.createTopic("PersistenceTopic");
		// 创建JMS consumer 按照目的地和唯一clientId标示。
		// TopicSubscriber是MessageConsumer的子接口
		TopicSubscriber ts = session.createDurableSubscriber(destination, "TT");
		// 设置监听
		ts.setMessageListener(new MessageListener() {
			public void onMessage(Message message) {
				message = (TextMessage) message;
				try {
					String value = ((TextMessage) message).getText();
					System.out.println("value2: " + value);
				} catch (JMSException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		});

	}
}

/************************ 持久订阅****************************/

1、消息生产者

package mqtest2;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.DeliveryMode;
import javax.jms.JMSException;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.jms.Topic;

import org.apache.activemq.ActiveMQConnectionFactory;

public class Producter2 {
	public static void main(String[] args) {
		String name = "topic_test2";
		ConnectionFactory connectionFactory = null;
		Connection connection = null;
		Session session = null;
		Topic topic = null;
		MessageProducer producter = null;
		TextMessage textMessage = null;
		connectionFactory = new ActiveMQConnectionFactory("admin", "admin",
				"tcp://127.0.0.1:61616");
		try {
			connection = connectionFactory.createConnection();
			connection.start();
			session = connection.createSession(Boolean.FALSE,
					Session.AUTO_ACKNOWLEDGE);
			topic = session.createTopic(name);
			producter = session.createProducer(topic);
			// 持久化消息
			producter.setDeliveryMode(DeliveryMode.PERSISTENT);
			// 消息对象
			textMessage = session.createTextMessage("one test!");
			// 发送消息
			producter.send(textMessage);
			System.out.println("发送结束！");
		} catch (JMSException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

2、消息消费者

package mqtest2;

import javax.jms.Connection;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.Queue;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.jms.Topic;

import org.apache.activemq.ActiveMQConnectionFactory;

public class Receive2 {
	public static void main(String[] args) {
		String clientid = "producter2";
		String name = "topic_test2";
		ActiveMQConnectionFactory connectionFactory = null;
		Connection connection = null;
		Session session = null;
		Topic topic = null;
		MessageConsumer consumer = null;
		try {
			connectionFactory = new ActiveMQConnectionFactory("admin", "admin",
					"tcp://127.0.0.1:61616");
			connection = connectionFactory.createConnection();
			connection.setClientID(clientid);
			connection.start();
			session = connection.createSession(Boolean.FALSE,
					Session.AUTO_ACKNOWLEDGE);
			topic = session.createTopic(name);
			consumer = session.createDurableSubscriber(topic, clientid);
			consumer.setMessageListener(new MessageListener() {
				public void onMessage(Message message) {
					message = (TextMessage) message;
					try {
						String value = ((TextMessage) message).getText();
						System.out.println("value2: " + value);
					} catch (JMSException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
				}
			});
		} catch (JMSException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

上面是发布订阅传送模型的非持久化订阅和持久化订阅的demo。

非持久化订阅没有什么硬性的要求，但持久化订阅是有硬性要求的即：

（1）、发送的消息是持久化的。

（2）、activemq区分消费者是通过clientID和订阅主题名称来区分的。

（3）、按照订阅主题名称和给连接设置的id(ClientID)来创建一个消息消费者对象：consumer = session.createDurableSubscriber(topic, clientid);

（4）、订阅主题名称和设置的ClientID组合起来必须是唯一的。

（5）、使用相同的“clientID”和主题名称，则认为是同一个消费者。两个程序使用相同的“clientID”，则同时只能有一个连接到activemq，第二个连接的会报错。

参考文档：http://blog.youkuaiyun.com/zhu_tianwei/article/details/46303347