JMS Pub/Sub (Alibaba Cloud account or RAM user)

Messaging process

Obtain an endpoint

You must obtain an endpoint of your instance in the Message Queue for RabbitMQ console. Before you send and receive messages, you must specify the endpoint in the code of the producer and consumer. Then, the producer and consumer can access the Message Queue for RabbitMQ instance by using the endpoint.

1. Log on to the Message Queue for RabbitMQ console.
2. In the Resource Distribution section of the Overview page, select the region where your instance is located.
3. On the Instances page, click the name of your instance.
4. On the Endpoint Information tab of the Instance Details page, move the pointer to the type of the endpoint that you want to use. Then, click the icon on the right side of the endpoint to copy the endpoint.

   Type	Description	Example
   Public endpoint	You can access an instance from the Internet to read and write data. By default, pay-as-you-go instances have public endpoints. To use a public endpoint for a subscription instance, you must select a public endpoint when you create the subscription instance.	XXX.mq-amqp.cn-hangzhou-a.aliyuncs.com
   VPC endpoint	You can access an instance from a virtual private cloud (VPC) to read and write data. By default, both pay-as-you-go and subscription instances have VPC endpoints.	XXX.mq-amqp.cn-hangzhou-a-internal.aliyuncs.com

Add JMS dependencies

Add the following dependencies to the pom.xml file:

<dependency>
    <groupId>com.rabbitmq</groupId>
    <artifactId>amqp-client</artifactId>
    <version>5.5.0</version> <!-- All versions of open source RabbitMQ are supported. -->
</dependency>
<dependency>
    <groupId>com.alibaba.mq-amqp.jms</groupId>
    <artifactId>mq-amqp-jms-client</artifactId>
    <version>1.11.2-1.0.0</version>
    <exclusions>
        <exclusion>
            <groupId>com.rabbitmq</groupId>
            <artifactId>amqp-client</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.4</version>
</dependency>
<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-simple</artifactId>
    <version>1.7.25</version>
    <scope>compile</scope>
</dependency>

Generate a pair of username and password

For more information, see Create a static username/password pair.

Nondurable subscriptions

Create, compile, and run the Subscriber.java class.

import com.rabbitmq.jms.admin.RMQConnectionFactory;
import com.rabbitmq.jms.client.AmqpConnectionFactoryPostProcessor;
import javax.jms.*;

public class Subscriber {
    public static String DESTINATION = "systemA.systemB.Price.*";

    public static RMQConnectionFactory getRMQConnectionFactory() {
        RMQConnectionFactory connectionFactory = new RMQConnectionFactory();
        connectionFactory.setHost("xxx.xxx.aliyuncs.com");
        connectionFactory.setUsername("${Username}");
        connectionFactory.setPassword("${Password}");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("VhostName");
        connectionFactory.setAmqpConnectionFactoryPostProcessor(new AmqpConnectionFactoryPostProcessor() {
            @Override
            public void postProcess(com.rabbitmq.client.ConnectionFactory cf) {
                cf.setAutomaticRecoveryEnabled(true);
                cf.setNetworkRecoveryInterval(5000);
                System.out.println(cf.getPassword());
            }
        });
        return connectionFactory;
    }

    public static void main(String[] args) throws Exception {
        RMQConnectionFactory connectionFactory = getRMQConnectionFactory();
        TopicConnection connection = connectionFactory.createTopicConnection();
        TopicSession session = connection.createTopicSession(false, Session.AUTO_ACKNOWLEDGE);
        Topic destTopic = session.createTopic(DESTINATION);
        TopicSubscriber subscriber = session.createSubscriber(destTopic);
        connection.start();
        while (true) {
            Message msg = subscriber.receive(1000);
            if (msg == null) {
                System.out.println("No new message, sleeping 5 secs");
                Thread.sleep(5 * 1000);
                continue;
            }
            if (msg instanceof TextMessage) {
                String body = ((TextMessage) msg).getText();
                System.out.println(body);
            } else {
                System.out.println("Unexpected message type: " + msg.getClass());
            }
        }
    }
}

Durable subscriptions

Create, compile, and run the DurableSubscriber.java class.

import com.rabbitmq.jms.admin.RMQConnectionFactory;
import com.rabbitmq.jms.client.AmqpConnectionFactoryPostProcessor;
import javax.jms.*;

public class DurableSubscriber {
    public static String DESTINATION = "systemA.systemB.Price.*";
    public static String CLIENT_ID = "client_id";
    public static String SUBSCRIBER_NAME = "subscriber_name";

    public static RMQConnectionFactory getRMQConnectionFactory() {
        RMQConnectionFactory connectionFactory = new RMQConnectionFactory();
        connectionFactory.setHost("xxx.xxx.aliyuncs.com");
        connectionFactory.setUsername("${Username}");
        connectionFactory.setPassword("${Password}");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("${VhostName}");
        connectionFactory.setAmqpConnectionFactoryPostProcessor(new AmqpConnectionFactoryPostProcessor() {
            @Override
            public void postProcess(com.rabbitmq.client.ConnectionFactory cf) {
                cf.setAutomaticRecoveryEnabled(true);
                cf.setNetworkRecoveryInterval(5000);
                System.out.println(cf.getPassword());
            }
        });
        return connectionFactory;
    }


    public static void main(String[] args) throws Exception {
        RMQConnectionFactory connectionFactory = getRMQConnectionFactory();
        TopicConnection connection = connectionFactory.createTopicConnection();
        connection.setClientID(CLIENT_ID);
        TopicSession session = connection.createTopicSession(false, Session.AUTO_ACKNOWLEDGE);
        Topic Topic = session.createTopic(DESTINATION);
        TopicSubscriber subscriber = session.createDurableSubscriber(Topic,SUBSCRIBER_NAME);
        connection.start();
        while (true) {
            Message msg = subscriber.receive(1000);
            if (msg == null) {
                System.out.println("No new message, sleeping 5 secs");
                Thread.sleep(5 * 1000);
                continue;
            }
            if (msg instanceof TextMessage) {
                String body = ((TextMessage) msg).getText();
                System.out.println(body);
            } else {
                System.out.println("Unexpected message type: " + msg.getClass());
            }
        }
    }
}

Send messages

Create, compile, and run the Publisher.java class.

import com.rabbitmq.jms.admin.RMQConnectionFactory;
import com.rabbitmq.jms.client.AmqpConnectionFactoryPostProcessor;
import javax.jms.*;

public class Publisher {

    public static String DESTINATION = "systemA.systemB.Price.aaa";

    public static RMQConnectionFactory getRMQConnectionFactory() {
        RMQConnectionFactory connectionFactory = new RMQConnectionFactory();
        connectionFactory.setHost("xxx.xxx.aliyuncs.com");
        connectionFactory.setUsername("${Username}");
        connectionFactory.setPassword("${Password}");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("${VhostName}");
        connectionFactory.setAmqpConnectionFactoryPostProcessor(new AmqpConnectionFactoryPostProcessor() {
            @Override
            public void postProcess(com.rabbitmq.client.ConnectionFactory cf) {
                cf.setAutomaticRecoveryEnabled(true);
                cf.setNetworkRecoveryInterval(5000);
                System.out.println(cf.getPassword());
            }
        });
        return connectionFactory;
    }

    public static void main(String[] args) throws JMSException {
        RMQConnectionFactory factory = getRMQConnectionFactory();
        TopicConnection connection = factory.createTopicConnection();
        TopicSession session = connection.createTopicSession(false,Session.AUTO_ACKNOWLEDGE);
        TextMessage msg = session.createTextMessage("hello topic test1");
        Topic topic = session.createTopic(DESTINATION);
        TopicPublisher publisher = session.createPublisher(topic);
        publisher.send(msg);
        System.out.println("Message sent");
        session.close();
        connection.close();
    }
}