Ascii Tree Generator

AsciiTreeGenerator.java

public class AsciiTreeGenerator {

    public static void main(String[] args) {
        generateLines(Integer.parseInt(args[0]));
    }

    private static void generateLines(int height) {
        System.out.print(generateLine(height, 0));
    }

    private static String generateLine(int height, int line) {
        return (height > line) ?
                returnSpaces(calculateSpaces(height, line)) +
                        returnStars(calculateStars(line)) +
                        returnSpaces(calculateSpaces(height, line)) +
                        "\n" +
                        generateLine(height, line + 1)
                :
                returnSpaces((calculateStars(line) / 2) - 1) +
                        "|" +
                        returnSpaces((calculateStars(line) / 2) - 1);
    }

    private static String returnSpaces(int amount) {
        if (amount > 0)
            return returnSpaces(amount - 1) + " ";
        else
            return "";
    }

    private static String returnStars(int amount) {
        if (amount > 0)
            return returnStars(amount - 1) + "*";
        else
            return "";
    }

    private static int calculateSpaces(int height, int line) {
        return height - line - 1;
    }

    private static int calculateStars(int line) {
        return ((line + 1) * 2) - 1;
    }
}