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In short, you write, test and debug your client-side code in Java and let GWT cross-compiler convert it all into cross-browser JavaScript. When compiled the Client-side is now pure JavaScript and HTML. So, Rich Webapp built with GWT requires no browser plug-ins, no Web Start or JVM, no downloads, no special installations.
Only pay for what you use!
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With GWT, Google bets on the 6 milions Java developers community out of here. Furthermore, Sakai is based on a great stack of Java technologies.
GWT allows rapid development and debugging with common Java IDEs as Eclipse. Development time efficiency is our favorite advantages of GWT.
The built-in library of UI components will look very familiar to Java developers, particularly those having Swing experience.
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Open Source and Community Initiative
Free and well documented, GWT is not only a Google thing, since its an Open Source initiative under a friendly Apache 2.0 license.
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