How do I use Math.PI in Java?

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If you’re looking for an alternative to using JOptionPane for input, you can use Scanner, which is more commonly used in console-based Java applications. Here’s how you can modify your program to use Scanner instead of JOptionPane:

import java.util.Scanner;

public class NumericTypes {
    public static void main(String[] args) {
        double radius;
        double volume;
        double diameter;

        // Use Scanner for input
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter the diameter of a sphere: ");
        diameter = scanner.nextDouble(); // Read diameter as double

        radius = diameter / 2;
        volume = (4.0 / 3.0) * Math.PI * Math.pow(radius, 3);

        System.out.println("The radius for the sphere is " + radius);
        System.out.println("The volume of the sphere is " + volume);
    }
}

Explanation:

  1. This approach uses Scanner to read the input from the console instead of a GUI dialog box.
  2. It works similarly but allows you to interact with the program in the terminal or console.