Simple test ----Compute the area of a circle

import java.util.Scanner;                  //Scanner is in the java.util package
import javax.swing.JOptionPane;

public class Java_test {
    public static void main(String args[]) {
        double radius;
        double area;
        
        Scanner input=new Scanner(System.in);    //Create a Scanner object

        //Prompt the user to enter a radius

        System.out.print("Please enter a number for radius: ");
        radius=input.nextDouble();          //Input a radius

        input.close();

        area=3.14159*radius*radius;
        System.out.println("The area of a circle with radius "+radius+" is "+area);
        
        //Display in a message dialog box
        JOptionPane.showMessageDialog(null,"The area of a circle with radius "
        +radius+" is "+area, "Compute area of circle",
                JOptionPane.INFORMATION_MESSAGE);
        
        
    }

}