How to retrive all unread messages from a topic?

Question

Hello!
          I have a webapp that stores TextMessages in a Topic in WebLogic.
          I have an ejbapp (Message driven bean) that reads messages from the topic.
          If both are up and running the ejbapp reads all messages sent from the webapp to the topic.
          But if I stop the ejbapp for a while and sends a couple of messages to the topic and then deploy the ejbapp again, then the ejbapp does not read the unconsumed messages. If I send a new message to the topic the ejbapp reads that new messages but it does not get the previous messages that are on the topic.
          Is this the way it should work? Or could I get the message driven bean to consume all the messages that it has not consumed from the topic when it starts?
          My weblogic-ejb-jar.xml looks like:
          <pre><!DOCTYPE weblogic-ejb-jar PUBLIC '-//BEA Systems, Inc.//DTD WebLogic 8.1.0 EJB//EN' 'http://www.bea.com/servers/wls810/dtd/weblogic-ejb-jar.dtd'>
          <weblogic-ejb-jar>
          <weblogic-enterprise-bean>
          <ejb-name>OrderManagerMDB</ejb-name>
          <message-driven-descriptor>
          <pool>
          <max-beans-in-free-pool>200</max-beans-in-free-pool>
          <initial-beans-in-free-pool>20</initial-beans-in-free-pool>
          </pool>
          <destination-jndi-name>jms/OrdersTopic</destination-jndi-name>
          <connection-factory-jndi-name>jms/OrdersConnectionFactory</connection-factory-jndi-name>
          </message-driven-descriptor>
          <enable-call-by-reference>True</enable-call-by-reference>
          </weblogic-enterprise-bean>
          </weblogic-ejb-jar></pre>
          And my ejb-jar.xml looks like:
          <pre><!DOCTYPE ejb-jar PUBLIC '-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN' 'http://java.sun.com/dtd/ejb-jar_2_0.dtd'>
          <ejb-jar>
          <enterprise-beans>
          <message-driven>
          <ejb-name>OrderManagerMDB</ejb-name>
          <ejb-class>brownbagwarehouse.OrderManagerMDB</ejb-class>
          <transaction-type>Container</transaction-type>
          <acknowledge-mode>Auto-acknowledge</acknowledge-mode>
          <message-driven-destination>
          <destination-type>javax.jms.Topic</destination-type>
          </message-driven-destination>
          </message-driven>
          </enterprise-beans>
          </ejb-jar></pre>
          My MDB onMessage looks like:
          <pre>public void onMessage(Message message)
               try
                    TextMessage textMessage = (TextMessage)message;
                    System.out.println(textMessage.getText());
               catch(Exception e)
                    e.printStackTrace();
          </pre>
          Best regards
          Fredrik

Answer 1

For subscriptions to continue to exist even while no subscriber is attached they need to be "durable". See the EJB programmer's guide, and search for "durable" in the MDB doc.
          In JMS terminology these are termed "durable subscriptions".
          Tom