examples.jms.scheduled-message.readme.html Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of hornetq-resources
The newest version!

  
    HornetQ Scheduled Message Example
    
    
    
  
  
     JMS Scheduled Message Example

     This example shows you how to send a scheduled message to a JMS Queue using HornetQ.
     A Scheduled Message is a message that will be delivered at a time specified by the sender. To do this, 
     simply set a HDR_SCHEDULED_DELIVERY_TIME header property. The value of the property should be the time of 
     delivery in milliseconds. 
     
     In this example, a message is created with the scheduled delivery time set to 5 seconds after the current time.


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

        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 producer = session.createProducer(queue);
       

        We create a JMS text message that we are going to send.
                   TextMessage message = session.createTextMessage("This is a scheduled message message which will be delivered in 5 sec.");
        

        We schedule the delivery time to be 5 sec later.
                   
            long time = System.currentTimeMillis();
            time += 5000;
            message.setLongProperty(MessageImpl.HDR_SCHEDULED_DELIVERY_TIME.toString(), time);
           
        

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

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

        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 use a blocking receive() to consume the message and see when the message arrives.
                   TextMessage messageReceived = (TextMessage) messageConsumer.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();
              }
           }
        

     
     
     More information
     
     
         User Manual's Scheduled Messages chapter