JMS HTTP Example

This example shows you how to configure ActiveMQ to use the HTTP protocol as its transport layer.

ActiveMQ supports a variety of network protocols to be its underlying transport without any specific code change.

This example is taken from the queue example without any code change. By changing the configuration file, one can get ActiveMQ working with HTTP transport.

All you need to do is open the server0/activemq-configuration.xml and enable HTTP like the following

      
      <connector name="netty-connector">
         <factory-class>org.apache.activemq.core.remoting.impl.netty.NettyConnectorFactory</factory-class>
         <param key="activemq.remoting.netty.http-enabled" value="true" type="Boolean"/>
         <param key="activemq.remoting.netty.port" value="8080" type="Integer"/>
      </connector>

      <!-- Acceptors -->

      <acceptor name="netty-acceptor">
         <factory-class>org.apache.activemq.core.remoting.impl.netty.NettyAcceptorFactory</factory-class>
         <param key="activemq.remoting.netty.port" value="8080" type="Integer"/>
      </acceptor>
      
      

Example step-by-step

To run the example, simply type mvn verify from this directory

1. First we need to get an initial context so we can look-up the JMS connection factory and destination objects from JNDI. This initial context will get it's properties from the client-jndi.properties file in the directory ../common/config

           InitialContext initialContext = getContext();
        

2. We look-up the JMS queue object from JNDI

           Queue queue = (Queue) initialContext.lookup("/queue/exampleQueue");
        

3. We look-up the JMS connection factory object from JNDI

           ConnectionFactory cf = (ConnectionFactory) initialContext.lookup("/ConnectionFactory");
        

4. We create a JMS connection

           connection = cf.createConnection();
        

5. We create a JMS session. The session is created as non transacted and will auto acknowledge messages.

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

6. We create a JMS message producer on the session. This will be used to send the messages.

          MessageProducer messageProducer = session.createProducer(topic);
       

7. We create a JMS text message that we are going to send.

           TextMessage message = session.createTextMessage("This is a text message");
        

8. We send message to the queue

           messageProducer.send(message);
        

9. We create a JMS Message Consumer to receive the message.

           MessageConsumer messageConsumer = session.createConsumer(queue);
        

10. We start the connection. In order for delivery to occur on any consumers or subscribers on a connection, the connection must be started

           connection.start();
        

11. The message arrives at the consumer. In this case we use a timeout of 5000 milliseconds but we could use a blocking 'receive()'

           TextMessage messageReceived = (TextMessage) messageConsumer.receive(5000);
        

12. And finally, always remember to close your JMS connections and resources after use, in a finally block. Closing a JMS connection will automatically close all of its sessions, consumers, producer and browser objects

           finally
           {
              if (initialContext != null)
              {
                initialContext.close();
              }
              if (connection != null)
              {
                 connection.close();
              }
           }