Java UI API - DocumentFieldChangeEvent

How do you set the oldField and newField in the new Java UI API: DocumentFieldChangeEvent(NotesUIField oldField, NotesUIField newField) .

I’m trying to figure out how to arrange the events and listeners. I have derived this code from the API which listens for all field changes, but would like to explictly declare them:

uidoc.addFieldListener(new DocumentFieldListener() {

public void fieldChanged(DocumentFieldChangeEvent arg0) {						 

	MessageDialog.openInformation(c.getShell(), "Star Wars",

	arg0.getNewField().getText());					

}					

});