Introduction to Programming

Inheritance

A class can acquire (inherit) all the non-private non-static members, so that when we use the object of this class, we cannot have any idea where these members actually reside – in this class or in the class from which they were inherited. To indicate inheritance, the keyword extends is used. For example, consider the following classes:

class A {  private void m1(){...}  public void m2(){...}}class B extends class A {  public void m3(){...}}class C extends class B {}

In this example, the objects of classes B and C behave as if each of them has methods m2() and m3(). The only limitation is that a class can extend one class only. Class A is a base (or parent) class for both class B and class C. Class B is a base class for class C