A Topic object encapsulates a provider-specific topic name.
It is the way a client specifies the identity of a topic to JMS API methods.
For those methods that use a Destination as a parameter, a
Topic object may used as an argument . For
example, a Topic can be used to create a MessageConsumer
and a MessageProducer
by calling:
-
Session.CreateConsumer(Destination destination)
-
Session.CreateProducer(Destination destination)
Many publish/subscribe (pub/sub) providers group topics into hierarchies
and provide various options for subscribing to parts of the hierarchy. The
JMS API places no restriction on what a Topic object
represents. It may be a leaf in a topic hierarchy, or it may be a larger
part of the hierarchy.
The organization of topics and the granularity of subscriptions to
them is an important part of a pub/sub application's architecture. The JMS
API
does not specify a policy for how this should be done. If an application
takes advantage of a provider-specific topic-grouping mechanism, it
should document this. If the application is installed using a different
provider, it is the job of the administrator to construct an equivalent
topic architecture and create equivalent Topic objects. |
