GWT-cs is a GWT module that allows developers to construct their GWT client side code using Spring IoC. It combines the powerful features of deferred binding and generator from GWT and inverse of control from Springframework, so that developers can define their application structures not only of their server code, but also of their client side GWT class beans.
GWT-cs features a tiny archive file with only two classes and one interface. The current release (v0.11) supports a subset of the Spring IoC functions that are enough to let developers to build their GWT application structures. GWT-cs does not dictate how it is done, but leaves the door fully open for anybody to do it in his own way. Typically, a bean defined in Spring xml configuration file would be a GWT Composite class and one can define one or more beans to collaborately build a page.
Source : http://code.google.com/p/gwt-cs/