Question

Please use C++.

Write a class named Circle that has a double data member named radius and a static double data member named maxRadius. It should have a default constructor that initializes the radius to 1.0. It should have a constructor that takes a double and uses it to initialize the radius. It should have a method called calcArea that returns the area of the Circle (use 3.14159 for pi). It should have a static set method for the maxRadius. It should also contain the definition of an exception class named IllegalRadius, which will contain a double data member called badRadius and a constructor that takes a double and uses it to initialize badRadius. The static maxRadius data member should be initialized to 10.0.  The Circle constructor that takes a parameter should throw an IllegalRadiusException if the parameter exceeds the maxRadius.

Write a main function in a separate file. It should ask the user to input a value for the maximum radius and sets maxRadius to that value. It should then ask the user for a radius, and then create a Circle with that radius. Next it should print out the area of that Circle. Your function should use try/catch to handle the possible exception. If an IllegalRadius exception is thrown, the program should print out an error message as shown below:

Enter the maxRadius for Circles.
7.0
Enter the radius for a new Circle object.
6.0
The Circle object was successfully created.
The area of the circle is 113.097.

Enter the maxRadius for Circles.
6.0
Enter the radius for a new Circle object.
7.0
The Circle object could not be created.
A radius of 7 exceeds the maximum allowed radius.

Answer 1

Circle.h

#ifndef CIRCLE_H
#define CIRCLE_H

class Circle {
public:
    double radius;
    static double maxRadius;
    Circle();
    void setRadius(double);
    void setMaxRadius(double);
    double calcArea();
};

#endif

Circle.cpp

#include <iostream>
#include "Circle.h"

double Circle::maxRadius = 10.0;

Circle::Circle() {
    this->radius = 1.0;
}

void Circle::setRadius(double r) {
    this->radius = r;
    if (r > maxRadius) {
        throw r;
    }
}

void Circle::setMaxRadius(double mr) {
    maxRadius = mr;
}

double Circle::calcArea() {
    return (3.14159 * radius * radius);
}

таin.cpp

#include <iostream>
#include "Circle.h"

using namespace std;

int main() {
    Circle c;
    double mr, r;

    cout << "Enter the maxRadius for Circles: ";
    cin >> mr;
    c.setMaxRadius(mr);

    cout << "\nEnter the radius for a new Circle object: ";
    try {
        cin >> r;
        c.setRadius(r);
    } catch (double badRadius) {
        cerr << "The Circle object could not be created." << "\n";
        cout << "A radius of " << badRadius << " exceeds the maximum allowed radius." << endl;
        return 0;
    }

    cout << "\nThe area of the circle is " << c.calcArea() << "\n";
}