上游充通大 ParisTech SHANGHAI JIAO TONG UNIVERSITY INSTITUT DES SCIENCES ET TECHNOLOGIES PARIS INSTITUTE OF TECHNOLOGY Circle New objects are created from a class by invoking a constructor.You can think of the class itself as a sort of factory for stamping out new instances. 。( Consider making a new circle object: mycircle Circle(Point (0,0),20) circle,the name of the class,is used to invoke the constructor. 7Circle • New objects are created from a class by invoking a constructor. You can think of the class itself as a sort of factory for stamping out new instances. • Consider making a new circle object: myCircle = Circle(Point(0,0),20) • Circle, the name of the class, is used to invoke the constructor. 7