Java Reference
In-Depth Information
lar way (timing out after 2.5 minutes and retrying requests after 5 seconds if they aren't yet
acknowledged). The value given in the
wsu:id
must be unique within the WSDL. You can
write several different policies and then hook them to a port binding. So you could write a few
different port bindings and allow clients to choose their terms.
If you examine the
wsdl:binding
element, you'll see that the binding has a name that repres-
ents the
MyPort
type. It's the binding, and not the port itself, that contains the reference to the
RM policy.
NOTE
Policies are conventionally defined at the top of the WSDL, though the WSDL will validate wherever
you put them.
Now when you deploy your service on a container that supports reliable messaging, your ser-
vice will use it.
Discussion
Recall that WS-Policy is a general extension point specification that allows WSDL to extend
its capabilities to include functionality afforded by other specifications concerned with some
particular aspect of Quality of Service. These might include reliable messaging, atomic trans-
actions, or security.
NOTE
One problem with WS-ReliableMessaging is the difficulty presented in clustering the reliable service.
The sequence ID needs to be shared between the nodes in the cluster. The scalability of services using
RM is also jeopardized because the client and server must participate in a stateful conversation.
See Also
Configuring a Java Client with Reliable Messaging
To see how to set up a client for use with
the reliable service.
