calculate circle area and perimeter with java code example

Example: Java program to calculate area of a circle

import java.util.Scanner;
public class CalculateAreaOfCircle
{
   public static void main(String[] args)
   {
      double radius;
      double pi = 3.1415, area;
      Scanner sc = new Scanner(System.in);
      System.out.println("Please enter radius of circle: ");
      radius = sc.nextDouble();
      area = pi * radius * radius;
      System.out.println("Area of circle: " + area);
      sc.close();
   }
}