Factorial - iterative & recursive

import java.util.Scanner;

/**
 * Write a description of class FactorialIterativeRecursive here.
 *
 * @author (Ruari Mears)
 * @version (1.1.3)
 */
public class FactorialIterativeRecursive
{
    /**
     * Uses nanoTime() to count execution time for each approach.
     */
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int input;
        int method;
        long begin;
        long end;
        long timeElapsed;

        System.out.println("Calculating factorial.");
        System.out.print("Enter a number: ");
        input = Integer.parseInt(scanner.nextLine());
        System.out.println("How do you want to calculate factorial of " + String.valueOf(input) + ":");
        System.out.println("1. Iteratively - using for");
        System.out.println("2. Iteratively - using while");
        System.out.println("3. Recursively.");
        System.out.print("Enter a number: ");
        method = Integer.parseInt(scanner.nextLine());

        switch (method) {
            case 1:
                begin = System.nanoTime();
                System.out.println("The result is: " + getFactorialIterationFor(input));
                end = System.nanoTime();
                timeElapsed = end - begin;
                System.out.println("The iterative (for) approach took "
                    + String.valueOf(timeElapsed) + "ns");
                break;
            case 2:
                begin = System.nanoTime();
                System.out.println("The result is: " + getFactorialIterationWhile(input));
                end = System.nanoTime();
                timeElapsed = end - begin;
                System.out.println("The iterative (while) approach took "
                    + String.valueOf(timeElapsed) + "ns");
                break;
            case 3:
                begin = System.nanoTime();
                System.out.println("The result is: " + getFactorialRecursion(input));
                end = System.nanoTime();
                timeElapsed = end - begin;
                System.out.println("The recursive approach took "
                    + String.valueOf(timeElapsed) + "ns");
                break;
        }
    }

    /**
     * Implementation of iterative (for) factorial from:
     * https://stackabuse.com/calculate-factorial-with-java-iterative-and-recursive/
     */
    public static int getFactorialIterationFor(int n)
    {
        int result = 1;

        if (n > 1) {
            for (int i = 1; i <= n; i++) {
                result = result * i;
            }
            return result;
        } else {
            System.out.println("n has to be positive");
            return result;
        }
    }

    /**
     * Implementation of iterative (while) factorial from:
     * https://stackabuse.com/calculate-factorial-with-java-iterative-and-recursive/
     */
    public static int getFactorialIterationWhile(int n) {
        int result = 1;
        while (n > 1) {
            result = result * n;
            n -= 1;
        }
        return result;
    }

    /**
     * Implementation of recursive factorial from:
     * https://stackabuse.com/calculate-factorial-with-java-iterative-and-recursive/
     */
    public static int getFactorialRecursion(int n) {
        if (n <= 1) {
            return 1;
        } else {
            return n * getFactorialRecursion(n-1);
        }
    }
}