Public class Circle {
//declaring the instance variable
protected double radius;
public Circle(double radius) {
this.radius = radius;
}
// other method definitions here
public double getArea() {
return Math.PI*radius*radius;
}//this method returns the area of the circle
}// end of class circle
public class Cylinder extends Circle {
//declaring the instance variable
protected double length;
public Cylinder(double radius, double length) {
super(radius);
this.length = length;
}
// other method definitions here
public double getArea() { // method overriden here
return 2*super.getArea()+2*Math.PI*radius*length;
}//this method returns the cylinder surface area
}// end of class Cylinder
Below is the code to instantiate the above two classes:
Circle myCircle;
myCircle = new Circle(1.20);
Cylinder myCylinder;
myCylinder = new Cylinder(1.20,2.50);