BluePenCore
+ BluePenCore()+ void wirteWord(String s)
BallPen
+getPenCore():PenCore
BlackBallPen
+ getPenCore():PenCore
BlackPenCore
+ BlackPenCore()+ void wirteWord(String s)
PenCore
+abstract void wirteWord(String s)
BlueBallPen
RedPenCore
+ RedPenCore()+ void wirteWord(String s)
RedBallPen
