public static boolean isJavaIdentifier(@NotNull CharSequence str, int startIncl, int endExcl) {
    if (str.length() == 0) return false;
    Ref.BooleanRef isFirst = new Ref.BooleanRef();
    isFirst.element = true;
    return processCodePoints(str, startIncl, endExcl, codePoint -> {
      if (isFirst.element) {
        isFirst.element = false;
        if (!isJavaIdentifierStart(codePoint)) {
          return false;
        }
      } else {
        if (!isJavaIdentifierPart(codePoint)) {
          return false;
        }
      }
      return true;
    });
  }
public static boolean isJavaIdentifier(@NotNull CharSequence str, int startIncl, int endExcl)