Remembering the Future

Mediator vs. Controller I also brushed past an interesting discovery we've made about the duties of a client-side Controller in rich apps: It often speaks with (or encapsulates) a mediator bridge that links a client-side controller to a server-side controller in rich apps. I like to refer to this is an Application Mediator because rather than sending Data Transfer Objects from a server-side domain model over to a thin client, in many cases we're talking about distributing the domain model so that it can partially reside on the client, with asynchronous messaging between the tiers for synchronization of the various concerns; this seems to be the successful approach to achieving rich offline and occasionally-connected behaviors. This is a patterns topic worth exploring more deeply.