Currently, Action and Result interfaces extend Serializable interface. However Google recomends to use IsSerializable: http://code.google.com/intl/en/webtoolkit/doc/1.6/FAQ_Server.html#Does_the_G WT_RPC_system_support_the_use_of_java.io.Serializable

Personally my concern is need to use @SuppressWarnings("serial").

In an ideal client-server project, the server would not depend on large client- specific libraries. I might want to distribute the server as part of a web services application alone; having it depend upon gwt-dispatch.jar and gwt-servlet.jar would be embarassing. Currently, gwt-dispatch.jar could be split into two jar files: gwt- dispatch-client.jar would depend upon gwt-user.jar, and gwt-dispatch-shared.jar would be standalone. I could write my services to use the Action and Result interfaces bringing in no real code at all. Making Action and Result implement IsSerializable instead of Serializable would make that impossible.

Yeah, I'm reluctant to use IsSerializable for that reason. In fact, I'm hoping to split out the non-GWT-specific code into a separate library at some point.

A workaround would be to have a 'GwtAction' interface that also implemented IsSerializable. Or, just get people to provide their own base class that implements it themselves...

Anyway, food for thought...

I'm going to close this as 'Won't Fix'. I'd rather keep the core classes non-GWT-dependent (yes, even though it's called 'gwt-dispatch').