Java For Everyone: Compatible with Java 5, 6, and 7, 2nd Edition

CHAPTER 9

INHERITANCE AND INTERFACES

CHAPTER GOALS

To learn about inheritance

To implement subclasses that inherit and override superclass methods

To understand the concept of polymorphism

To be familiar with the common superclass Object and its methods

To work with interface types

CHAPTER CONTENTS

9.1 INHERITANCE HIERARCHIES

Programming Tip 9.1: Use a Single Class for Variation in Values, Inheritance for Variation in Behavior

9.2 IMPLEMENTING SUBCLASSES

Syntax 9.1: Subclass Declaration

Common Error 9.1: Replicating Instance Variables from the Superclass

Common Error 9.2: Confusing Super- and Subclasses

9.3 OVERRIDING METHODS

Common Error 9.3: Accidental Overloading

Common Error 9.4: Forgetting to Use super When Invoking a Superclass Method

Special Topic 9.1: Calling the Superclass Constructor

Syntax 9.2: Constructor with Superclass Initializer

9.4 POLYMORPHISM

Special Topic 9.2: dynamic Method Lookup and the Implicit Parameter

Special Topic 9.3: Abstract Classes

Special Topic 9.4: final Methods and Classes

Special Topic 9.5: Protected Access

How To 9.1: developing an Inheritance Hierarchy

Worked Example 9.1: Implementing an Employee Hierarchy for Payroll Processing

Video Example 9.1: Building a discussion Board

9.5 OBJECT: THE COSMIC SUPERCLASS

Syntax 9.3: The instanceof Operator ...