Pure Abstract Base Class Project to test the Basic Shape Circle and Rectangle using C++

Pure Abstract Base Class Project
Define a pure abstract base class called BasicShape. The Baaicshape class should
have the following members:
Private Member Variable:
area, a double used to hold the shape’s area.
Public Member Functions:
getArea. This function should return the value in the member variable area.
calcArea. This function should be a pure virtual function.
Next, define a class named Circle. It should be derived from the Basicshape class.
It should have the following members:
Private Member Variables:
centerX, a long integer used to hold the x coordinate of the circle’s center.
centerY, a long integer used to hold the y coordinate of the circle’s center.
radius, a double used to hold the circle’s radius.
Public Member Functions:
constructor-accepts values for centerX, centerY, and radius. Should call the
overridden calcArea function described below.
getCenterx-returns the value in centerX.
getCenterY-rerurns the value in centerY.
calcArea—calculates the area of the circle (area = 3.14159 …. radius …. radius)
and stores the result in the inherited member area.
Next, define a class named Rectangle. Ir should be derived from the BasicShape
class. It should have the following members:
Private Member Variables:
width, a long integer used to hold the width of the rectangle.
length, a long integer used to hold the length of the rectangle.
Public Member Functions:
constructor-accepts values for width and length. Should call the overridden
calCArea function described below.

get’Width-returns the value in width.
getLength– returns the value in length.
calCArea-calculates the area of the rectangle (area = length ” width) and stores
the result in the inherited member area.
After you have created these classes, create a driver program that defines a Circle
object and a Rectangle object. Demonstrate that each object properly calculates and
reports its area.

Answer:

//  Pure Abstract Base Class Project  
//	Driver program is used to test the BasicShape (Abstract Base Class), Circle 
//  (Derived Class) and Rectangle (Derived class).
//  The program asks for needed information for both a circle and rectangle and 
//  returns the area.
#include <iostream>
#include "Circle.h"
#include "Rectangle.h"
using namespace std;

int main()
{
	long x, y, length, width;
	double rad;

	// Demonstrate a Circle.
	cout << "Please enter the x coordinate of the circle's center: "; cin >> x;
	cout << "Please enter the y coordinate of the circle's center: "; cin >> y;
	cout << "Please enter the radius of the circle: "; cin >> rad;
	Circle c(x,y,rad);
	cout << "The area of the circle is " << c.getArea() << ".";

	// Demonstrate a Rectangle.
	cout << "\n\nPlease enter the length of the rectangle: "; cin >> length;
	cout << "Please enter the width of the rectangle: "; cin >> width;
	Rectangle r(width, length);
	cout << "The area of the rectangle is " << r.getArea() << ".\n";

	return 0;
}

Specification file for BasicShape base class

#ifndef BASICSHAPE_H
#define BASICSHAPE_H

class BasicShape
{
private:
	double area;

public:
	double getArea() 
		{return area;}

	virtual void calcArea() = 0;

	void setArea(double a) 
		{ area = a; }
};

#endif

Specification file for Circle derived class

#ifndef CIRCLE_H
#define CIRCLE_H
#include "BasicShape.h"

class Circle : public BasicShape
{
private:
	long centerX;
	long centerY;
	double radius;
public:
	Circle(long x, long y, double rad)
		{ centerX = x; centerY = y; radius = rad; calcArea(); }

	long getCenterX() 
		{	return centerX; }

	long getCenterY() 
		{ return centerY; }

	void calcArea()	
		{ double temp = 3.14159 * radius * radius;
    	  BasicShape::setArea(temp);
		}

	double getArea() 
		{ return BasicShape::getArea();}
};

#endif

Specification file for Rectangle derived class

#ifndef RECTANGLE_H
#define RECTANGLE_H
#include "BasicShape.h"

class Rectangle : public BasicShape
{
private:
	long width;
	long length;

public:
	Rectangle(long w, long l)
		{ width = w; length = l; calcArea(); }

	long getWidth() 
		{ return width; }

	long getLength() 
		{ return length; }

	void calcArea() 
		{ double temp = length * width; BasicShape::setArea(temp); }
};

#endif