Object Oriented Programming Through Java by Pearson

6.4 Inheritance: Packages: Interfaces

should declare them as protected. Accordingly, we have used accessor

methods in Line Nos. 32 and 33 to display these private variables.

Line No. 13: declared public method

ComputeGrade(). Line No. 30 classes it

with std object. Also this method takes std1 object as argument and

returns std1 object.

Line No. 30: calls method belonging to superclass Person :std.DisplayData().

This is the real power of Inheritance. Student1 has not written code

for DisplayData() but it is using the code of super.

6.2.1 Base Class/Super Class

A super class or base class, as it is differently called in the literature, is a class from which other

classes are derived. We can say that other classes extend to a base class.

The classes ...