GWT: Google Web Toolkit

http://code.google.com/intl/zh-TW/webtoolkit/
http://code.google.com/intl/zh-TW/webtoolkit/examples/
http://code.google.com/intl/zh-TW/eclipse/docs/install-from-zip.html
http://code.google.com/intl/zh-TW/eclipse/docs/install-eclipse-3.4.html
http://code.google.com/intl/zh-TW/webtoolkit/download.html

You write your front end in the Java programming language and GWT compiles your source into highly optimized JavaScript.