Java Mean Average

import java.util.Scanner;
import java.util.ArrayList;
public class InteractiveMeanCalculator {
    public static double calculateMean(ArrayList<Double> data) {
        if (data.isEmpty()) {
            System.out.println("No data entered.");
            return 0;
        }
        double sum = 0;
        for (double num : data) {
            sum += num;
        }
        return sum / data.size();
    }
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        ArrayList<Double> numbers = new ArrayList<>();
        System.out.println("How many numbers do you want to enter? ");
        int count = scanner.nextInt();
        for (int i = 1; i <= count; i++) {
            System.out.println("Enter number " + i + ": ");
            double num = scanner.nextDouble();
            numbers.add(num);
        }
        double mean = calculateMean(numbers);
        System.out.println("The mean of the entered numbers is: " + mean);
        scanner.close();
    }
}
InteractiveMeanCalculator.main(null);

How many numbers do you want to enter? 
Enter number 1: 
Enter number 2: 
Enter number 3: 
The mean of the entered numbers is: 20.0