GWT

Google Web Toolkit (GWT) Java AJAX Programming by Prabhakar Chaganti is an excellent book for GWT beginners. The language is straightforward and easy to follow.

The book starts with a short introduction to Ajax. It then talks about the steps to follow for getting started with GWT 1.3.3. The first chapter essentially familiarizes you with the GWT extract - the folders and their contents. It also talks about the sample applications that come with the download.