CrossingStars

/*
 * Objective:  Print "cross" or "star" pattern from this post:
 *      https://www.facebook.com/groups/java4developers/permalink/1742344979155475/
 * JUnit tests:
 *      https://pastebin.com/pVw3CUY0
 * Additional tests, and tweaked for someone else's implementation:
 *      https://pastebin.com/bZMmLnQs
 */

public class CrossingStars {

    public static void printCrossingStars(final int n) {
        for (int i = n; i >= 1; --i) {
            printSideLine(n, i);
        }

        printMainLine(n);

        for (int i = 1; i <= n; ++i) {
            printSideLine(n, i);
        }
    }

    private static void printMainLine(int n) {
        for (int j = 1; j <= n; ++j) {
            System.out.print(nOf(j + 1, '*'));
        }
        if (n > 0) {
            System.out.println();
        }
    }

    private static void printSideLine(int n, int i) {
        for (int j = 1; j <= n; ++j) {
            System.out.print(nOf(j, ' '));
            System.out.print( (j < i) ? ' ' : '*');
        }
        System.out.println();
    }

    private static String nOf(final int numberOf, final char chr) {
        final StringBuilder stringBuilder = new StringBuilder();
        for (int count = 0; count < numberOf; ++count) {
            stringBuilder.appendCodePoint(chr);
        }
        return stringBuilder.toString();
    }

}