question: public UndoEvent ( UndoActionInterface parentObj , FieldIdEnum fieldId , Object oldValue , Object newValue ) { this . parentObj = parentObj ; this . fieldId = fieldId ; this . oldValue = oldValue ; this . newValue = newValue ; representation = String . format ( "Storing value : %s Old : %s New : %s" , fieldId . toString ( ) , oldValue , newValue ) ; }
target:  Instantiates a new undo event.