Please include all of the GUI classes in your diagram, but you can be very selective about the methods and fields that you include within those classes.
Certainly DO NOT include a million private @FXML fields-- maybe just any public fields, or private fields that have public getters/setters that other classes may use.
I'm doubtful you want to include all the @fxml event handler methods either. Maybe just the most important ones, and the non-private methods that get called from other classes. Or the methods that are most important for relating to the data model, which is what we are most interested in discussing.
