KoalaGML
KoalaGML, the koala GUI Markup Language, allows developers to rapidly generate graphical user interfaces by writing XML documents that define the layout and content of the interfaces. It is both a markup language and a toolset for generating the Java GUI code from the markup. Inspired by Java Server Pages (JSP), koalaGML consists of a rich and growing set of features, including: session beans, custom imports, exception handling, custom error forms, relative layout of elements (with tables ala HTML) and a huge set of widgets.
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License
GNU Library or Lesser General Public License (LGPL)