Applications interact with the notification broker through the Web service message exchanges defined in the WS-Notification specifications.
The following diagram shows the WS-Notification roles:
These roles equate to three Web service port types against which the application can invoke operations:
The first point of contact for an application will always be the NotificationBroker port type. Applications invoke operations against this endpoint to create subscriptions, insert notification events into the system or register themselves as publishers. The SubscriptionManager and PublisherRegistrationManager objects work with the NotificationBroker to provide the overall functionality.
References to the SubscriptionManager and PublisherRegistrationManager are returned to the application as a result of calls to the NotificationBroker. In particular a reference to the SubscriptionManager is returned from the Subscribe operation of the NotificationBroker. This allows an application to influence the lifecycle of the Subscription resource once it has been created. Similarly a reference to the PublisherRegistrationManager is returned from the RegisterPublisher operation on the NotificationBroker and allows the application to influence the lifecycle of the publisher registration.
Because applications interact with the broker entirely through WS-Notification message exchanges, the applications are unaware that the NotificationBroker, SubscriptionManager and PublisherRegistrationManager services are provided by WebSphere® Application Server. This means that you can modify the application to use any NotificationBroker provider, for example one provided by a different vendor or on a different server, by modifying the endpoint address against which the application makes its Web services invocations.
WS-Notification defines the following roles in which an application can interact with the NotificationBroker. These roles define the use cases for applications.
You can use any appropriate tooling to generate WS-Notification applications for use with the NotificationBroker. You take the WSDL exposed by a WS-Notification service point and use a development tool such as IBM® Rational® Application Developer to generate JAX-RPC stubs against which the application can be coded. For examples of this type of coding, see Developing applications that use WS-Notification.