| Generic remote access exception. A service proxy for any remoting
protocol and toolkit should throw this exception or subclasses of it,
to be able to transparently expose a plain Java business interface.
When using conforming proxies, switching the actual remoting toolkit
e.g. from Hessian to Burlap does not affect client code. The latter
works with a plain Java business interface that the service exposes.
A client object simply receives an implementation for the interface that
it needs via a bean reference, like it does for local beans too.
A client can catch RemoteAccessException if it wants to, but as
remote access errors are typically unrecoverable, it will probably let
such exceptions propagate to a higher level that handles them generically.
In this case, the client code doesn't show any signs of being involved in
remote access, as there aren't any remoting-specific dependencies.
Even when switching from a remote service proxy to a local implementation
of the same interface, this amounts to just a matter of configuration.
Obviously, the client code should be somewhat aware that it _could work_
on a remote service, for example in terms of repeated method calls that
cause unnecessary roundtrips etc. But it doesn't have to be aware whether
it actually works on a remote service or a local implementation, or
with which remoting toolkit under the hood.
author:
Juergen Hoeller
since:
14.05.2003 |
