Calculate Circle Perimeter using Java Example

/*

        Calculate Circle Perimeter using Java Example

        This Calculate Circle Perimeter using Java Example shows how to calculate

        Perimeter of circle using it's radius.

 */


import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;


public class CalculateCirclePerimeterExample {


    public static void main(String[] args) {


        int radius = 0;

        System.out.println("Please enter radius of a circle");


        try {

            // get the radius from console

            BufferedReader br = new BufferedReader(new InputStreamReader(

                    System.in));

            radius = Integer.parseInt(br.readLine());

        }

        // if invalid value was entered

        catch (NumberFormatException ne) {

            System.out.println("Invalid radius value" + ne);

            System.exit(0);

        } catch (IOException ioe) {

            System.out.println("IO Error :" + ioe);

            System.exit(0);

        }


        /*

         * Perimeter of a circle is 2 * pi * r where r is a radius of a circle.

         */


        // NOTE : use Math.PI constant to get value of pi

        double perimeter = 2 * Math.PI * radius;


        System.out.println("Perimeter of a circle is " + perimeter);

    }

}


/*

 * Output of Calculate Circle Perimeter using Java Example would be Please enter

 * radius of a circle 19 Perimeter of a circle is 119.38052083641213

 */