gui4j is a framework for describing graphical user interfaces completely in XML. The graphical user interface is created dynamically based on the xml definition.
Each GUI window is associated to exactly one top-level xml-file which can be defined using other xml-files. The top-level xml-file is read by one controller and each included xml-file might use another controller to structure complex GUI definitions.
There is a strong separation between the GUI and the Java code which implies that GUI definitions in the xml files can access Java methods, but Java methods cannot access GUI elements.