CSC/ECE 517 Fall 2011/ch6 6b ra

Subclassing

Introduction

Subclassing is one of the significant features of OO programming, which greatly increases the reusability of classes and also minimizes duplication of code. A subclass usually inherits some properties from a super class. A superclass consists of common features that can be extended over subclasses. It is extensively used in object oriented programming because of the reusability that can be achieved. Superclass and subclass are commonly called base and derived class. The relationship between a subclass and superclass can be represented by a simple UML diagram as shown below.     [Inheritance is a design principle in object oriented languages like Java. The reason behind inheritance is to reuse the code of existing objects or establish a subtype from an object. This greatly improves the efficiency and makes the code more readable as methods which are written only once can be used by a lot of subclasses.