I read through a few threads (simple web framework, java web development, etc). Very informative. However I have not seen a focus on the AJAX side of things. For the app I am trying to create, most of the client side will be written in Google GWT, and JSON will be used to communicate with the server side. In that case, all templating is pretty much useless.
For my purposes, which framework would be the simplest to setup and easiest to learn?
To clarify, I want a server side framework. GWT is great for client side, but I need something to generate json responses on the server side.