private static boolean isEmptyOrWhitespace(final String target) {
        if (target == null) {
            return true;
        }
        final int targetLen = target.length();
        if (targetLen == 0) {
            return true;
        }
        final char c0 = target.charAt(0);
        if ((c0 >= 'a' && c0 <= 'z') || (c0 >= 'A' && c0 <= 'Z')) {
            // Fail fast, by quickly checking first char without executing Character.isWhitespace(...)
            return false;
        }
        for (int i = 0; i < targetLen; i++) {
            final char c = target.charAt(i);
            if (c != ' ' && !Character.isWhitespace(c)) {
                return false;
            }
        }
        return true;
    }