I have used InterfaceCodeGenerator to generate classes for org.gnome.Mutter.DisplayConfig. The resulting classes are helpful but imperfect. For example, this crashes with a ClassCastException.

DisplayConfig displayConfig = connection.getRemoteObject("org.gnome.Mutter.DisplayConfig",
    "/org/gnome/Mutter/DisplayConfig", DisplayConfig.class);
GetCurrentStateTuple state = displayConfig.GetCurrentState();
List<GetCurrentStateMonitorsStruct> monitors = state.getMonitors();
GetCurrentStateMonitorsStruct m0 = monitors.get(0);

I read that “the InterfaceCodeGenerator is far from being perfect. It's just a helper to get started somehow”, but I thought I’d let you know in case you want to investigate. (I can share an example project if this would be helpful.)

Thanks for this project.