In chapter 9 you will learn: How inheritance promotes software reusability, the notions of superclasses and subclasses, to use keyword extends to create a class that inherits attributes and behaviors from another class, to use access modifier protected to give subclass methods access to superclass members, to access superclass members with super, how constructors are used in inheritance hierarchies. | 9 Object-Oriented Programming: Inheritance Say not you know another entirely, till you have divided an inheritance with him. Johann Kasper Lavater This method is to define as the number of a class the class of all classes similar to the given class. Bertrand Russell Good as it is to inherit a library, it is better to collect one. Augustine Birrell Save base authority from others books. William Shakespeare OBJECTIVES In this chapter you will learn: How inheritance promotes software reusability. The notions of superclasses and subclasses. To use keyword extends to create a class that inherits attributes and behaviors from another class. To use access modifier protected to give subclass methods access to superclass members. To access superclass members with super. How constructors are used in inheritance hierarchies. The methods of class Object, the direct or indirect superclass of all classes in Java. Introduction Superclasses and Subclasses protected . | 9 Object-Oriented Programming: Inheritance Say not you know another entirely, till you have divided an inheritance with him. Johann Kasper Lavater This method is to define as the number of a class the class of all classes similar to the given class. Bertrand Russell Good as it is to inherit a library, it is better to collect one. Augustine Birrell Save base authority from others books. William Shakespeare OBJECTIVES In this chapter you will learn: How inheritance promotes software reusability. The notions of superclasses and subclasses. To use keyword extends to create a class that inherits attributes and behaviors from another class. To use access modifier protected to give subclass methods access to superclass members. To access superclass members with super. How constructors are used in inheritance hierarchies. The methods of class Object, the direct or indirect superclass of all classes in Java. Introduction Superclasses and Subclasses protected Members Relationship between Superclasses and Subclasses Creating and Using a CommissionEmployee Class Creating a BasePlusCommissionEmployee Class without Using Inheritance Creating a CommissionEmployee– BasePlusCommissionEmployee Inheritance Hierarchy CommissionEmployee– BasePlusCommissionEmployee Inheritance Hierarchy Using protected Instance Variables CommissionEmployee– BasePlusCommissionEmployee Inheritance Hierarchy Using private Instance Variables Constructors in Subclasses Software Engineering with Inheritance Object Class (Optional) GUI and Graphics Case Study: Displaying Text and Images Using Labels Wrap-Up Introduction Inheritance Software reusability Create new class from existing class Absorb existing class’s data and behaviors Enhance with new capabilities Subclass extends superclass Subclass More specialized group of objects Behaviors inherited from superclass Can customize Additional .
