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.

:: current features ::
. NetBeans IDE plugin
. graphical (swing) generation and compilation frontend
. support for most common widgets (buttons, labels, combo boxes, input texts, lists, radio buttons, checkboxes, trees and text areas)
. custom scriptlet in widget events and values as well as on form load and close
. session beans support (ala JSP)
. multiple form handling (invoking and closing forms)
. tables for laying out widgets inside forms (like HTML layout)
. menus with separation lines and mnemonic character support
. custom java class imports
. custom error form for exception handling
. image support in most widgets
. pretty-printing of generated code with Jalopy
. forked execution in separate threads for long-timed operations