for (int i = 0; i < id.length(); i++) {
            char c = id.charAt(i);
            if (!isValidIdCharacter(c)) {
                return false;
            }
        }
        return true;
    }

    private boolean isValidIdCharacter(char c) {
        return c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9' || c == '-' || c == '_' || c == '.';
    }