Question

Create a class called circle stats that has 2 methods - JAVA

1) CalcPerimeter

2) CalcArea

it takes the radius and computes the area of the circle as long as the input is valid and doesn't equal -1.

the program needs to ask for user input and if input is -1 it will quit however all other negative values will be invalid.

Answer 1

import java.util.Scanner;

public class Circle {
    private double radius;

    public Circle() {
    }

    public Circle(double radius) {
        this.radius = radius;
    }

    public double getRadius() {
        return radius;
    }

    public void setRadius(double radius) {
        this.radius = radius;
    }

    public double CalcPerimeter() {
        return 2*Math.PI*radius;
    }

    public double CalcArea(){
        return radius*radius*Math.PI;
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Circle circle = new Circle();
        System.out.print("Enter radius: ");
        double radius = scanner.nextDouble();
        while (radius>0){
            circle.setRadius(radius);
            System.out.println("Area = "+circle.CalcArea());
            System.out.print("Enter radius: ");
            radius = scanner.nextDouble();
        }
    }
}

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