public static boolean isOctalLiteralText(String literalText) {
    if (literalText.charAt(0) != '0' || literalText.length() < 2) {
      return false;
    }
    final char c1 = literalText.charAt(1);
    return c1 == '_' || (c1 >= '0' && c1 <= '7');
  }
public static boolean isOctalLiteralText(String literalText)