Spring MessageListener multiple Messages - web-services

Question

I am implementing a Spring MessageListener that is listening to a JMS Queue to process messages containing XML.
My bean ProposalSOAListener will be processing about 5 or more XML messages from the queue. My code is below.
Is there a way to specify different methods on this class to handle different XML messages?
public class ProposalSOAListener implements MessageListener {
public void onMessage(Message message) {
if (message instanceof TextMessage) {
try {
System.out.println(((TextMessage) message).getText());
} catch (JMSException ex) {
throw new RuntimeException(ex);
}
}
else {
throw new IllegalArgumentException("Message must be of type TextMessage");
}
}
} // end of ProposalSOAListener class

Answer 1

There's a bunch of architectural questions begged by your question. Do you want this mesasge listener to do the work, or hand it off to another component? Are there transactional considerations at play? Do you have memory constraints - i.e. do you want streaming based XML processing or not? Do
The good news is that you have a lot of the pieces to this puzzle available to you within Spring.
A simple next step would be to use Spring Object XML Marshalling (OXM), choose one of the techniques, and wire the marshaller into your listener bean.
See http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/oxm.html
Another technique would be to use the Spring ApplicationEvent interface, read the messages coming in off the queue and publish them internally to listeners of the specific types. That could be used in combination with the above object marshalling.
Last but not least, if this is SOAP web services - you can take a look at Spring WS, it uses the similar message containers to pull messages off the wire, marshall them, and invoke a spring ws endpoint (ie. the service interface that satisfies that interface contract).
http://static.springsource.org/spring-ws/sites/2.0/reference/html/server.html#d4e907

Answer 2

Spring Integration project is highly recommended for this kind of a problem. Essentially you will have to implement a jms inbound gateway to get your message in. You can then transform this to an object at this point, then route the message to the appropriate service-activator component, which can map to your instance and method.