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    HornetQ JMS Temporary Queue Example
    
    
    
  
  
     JMS Temporary Queue Example

     This example shows you how to use a TemporaryQueue with HornetQ. First a temporary queue is created to send and receive a message and then deleted.
         Then another temporary queue is created and used after its connection is closed to illustrate its scope.
     A TemporaryQueue is a JMS queue that exists only within the lifetime of its connection. It is often used in request-reply
         type messaging where the reply is sent through a temporary destination. The temporary queue is often created as
         a server resource, so after using, the user should call delete() method to release the resources.
         Please consult the JMS 1.1 specification for full details.

     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 from JNDI. This initial context will get it's properties from the client-jndi.properties file in the directory ../common/config
                   initialContext = getContext();
        

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

        We Create a JMS connection
                   connection = cf.createConnection();
        
         
        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();
        
         
        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 Temporary Queue
                   Queue tempQueue = session.createTemporaryQueue();
        

        We create a JMS message producer to the temporary queue. This will be used to send the messages.
        	        MessageProducer messageProducer = session.createProducer(tempQueue);
        
         
        We create a JMS text message to send 
                   TextMessage message = session.createTextMessage("This is a text message");
        
   
        We send the message to the temporary queue
                   messageProducer.send(message);
        

        We create a message consumer of the temporary queue
                   MessageConsumer messageConsumer = session.createConsumer(tempQueue);
        

        We receive the message from the temporary queue
                   message = (TextMessage) messageConsumer.receive(5000);
        

        We close the consumer and producer before destroying the temporary queue
                   messageConsumer.close();
           messageProducer.close();
        

        We delete the temporary queue
                   tempQueue.delete();
        

        We create another temporary queue
                   TemporaryQueue tempQueue2 = session.createTemporaryQueue();
        

        We close the connection
                   connection.close();
        

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

        We create a new session
                   session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
        

        We try to access the tempQueue2 outside its lifetime, this will cause exception thrown
                   
         try
         {
            messageConsumer = session.createConsumer(tempQueue2);
            throw new Exception("Temporary queue cannot be accessed outside its lifecycle!");
         }
         catch (InvalidDestinationException e)
         {
            System.out.println("Exception got when trying to access a temp queue outside its scope: " + e);
         }
           
        

        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();
              }
           }