PureMVC, the well-known Java AS3 framework, is now available for Java and GWT. PureMVC is a lightweight framework for creating applications based upon the classic Model-View-Controller design meta-pattern.
The pureMVC Java Multicore Version supports modular programming, through the use of Multiton Core actors (instead of the Singletons used in the Standard Version).
It is also GWT compliant and is packaged with pipes utility which provides the capability for creating pipelines that pass messages between Cores.
Pipelines can contain filters, queues, splitting and merging tees, and more.