Google Web Toolkit.
The Google Web Toolkit is a free toolkit by Google to develop AJAX applications in the Java programming language. GWT supports rapid client/server development and debugging in any Java IDE. In a subsequent deployment step, the GWT compiler translates a working Java application into equivalent
JavaScript that programatically manipulates a web brower's HTML DOM using DHTML techniques. GWT emphasizes reusable, efficient solutions to recurring AJAX challenges, namely asynchronous remote procedure calls, history management, bookmarking, and cross-browser portability.