Interesting GWT Libraries

Google Web Toolkit (GWT) is a fantastic platform for developing rich internet applications (RIA).

I've been looking for different libraries to extend the functionality of GWT and have run into several interesting libraries hosted on Google Project. The following libraries seem to have interesting functionality, high development activity and good user feedback (+1).

GWT Query (GWTQuery):

    GwtQuery a.k.a. GQuery is a jQuery-like API written in GWT, which allows GWT to be used in progressive enhancement scenarios where perhaps GWT widgets are too heavyweight. It can also be used to find and improve your GWT widgets.

    GwtQuery is easy to learn for those using jQuery as they share the same api, aditionally gquery adds nice features like type-safe css, compile time optimisations, etc.

GWT Platform (GWTP)

A complete model-view-presenter framework to simplify your next GWT project.

GWTP was presented at Google I/O and you can find some slides here: Link

Google GIN (GIN)
For those who love Guice for dependency injection; this is the GWT version.

GIN (GWT INjection) brings automatic dependency injection to Google Web Toolkit client-side code. GIN is built on top of Guice and uses (a subset of) Guice's binding language. (See GuiceCompatibility for details.) By using GWT's compile-time Generator support, GIN has little-to-no runtime overhead compared to manual DI.

GWT Upload (GWTupload)

GwtUpload & JsUpload: File Upload Progress with pure javascript (Ajax)

GWT Test Utils

a framework to test GWT client side code very easily

GWT Test utils aims to replace the VERY slow GWTTestCase construct for unit testing GWT Widget code.

Spiffy UI

Spiffy UI framework: GWT made simple

Spiffy UI aims to help with the plumbing and the framework required to setup GWT project. See also the main website for Spiffy UI