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    HornetQ JMS Topic Example
    
    
    
  
  
     JMS Topic Example

     This example shows you how to send and receive a message to a JMS Topic with HornetQ.
     Topics are a standard part of JMS, please consult the JMS 1.1 specification for full details.
     A Topic is used to send messages using the publish-subscribe model, from a producer to 1 or more consumers.

     Example step-by-step
     To run the example, simply type ./build.sh (or build.bat on windows) from this directory

     
        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();
        

        We look-up the JMS topic object from JNDI
                   Topic topic = (Topic) initialContext.lookup("/topic/exampleTopic");
        

        We look-up the JMS connection factory object from JNDI
                   ConnectionFactory cf = (ConnectionFactory) initialContext.lookup("/ConnectionFactory");
        

        We create a JMS connection
                   connection = cf.createConnection();
        

        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);
        

        We create a JMS message producer on the session. This will be used to send the messages.
                  MessageProducer messageProducer = session.createProducer(topic);
       

        We create a JMS Message Consumer, messageConsumer1, to receive the message.
                    MessageConsumer messageConsumer = session.createConsumer(topic);
         

        We create a JMS Message Consumer, messageConsumer2, to also receive the message.
                  MessageConsumer messageConsumer2 = session.createConsumer(topic);
        

        We create a JMS text message that we are going to send.
                   TextMessage message = session.createTextMessage("This is a text message");
        

        We send message to the topic
                   messageProducer.send(message);
        

        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();
        

        The message arrives at the first consumer
                   TextMessage messageReceived = (TextMessage) messageConsumer1.receive();
        

        The message arrives at the second consumer
                   messageReceived = (TextMessage) messageConsumer2.receive();
        
        
        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();
              }
           }