private static @Nullable String generateIndentWhitespace(FormatProcessor processor,
                                                           CommonCodeStyleSettings.IndentOptions indentOptions,
                                                           FormattingDocumentModel documentModel,
                                                           int offset) {
    WhiteSpace whiteSpace = getWhiteSpaceAtOffset(offset, processor);
    if (whiteSpace != null) {
      final IndentInfo indent = calcIndent(offset, documentModel, processor, whiteSpace);
      return indent.generateNewWhiteSpace(indentOptions);
    }
    return null;
  }
private static @Nullable String generateIndentWhitespace(FormatProcessor processor,
                                                           CommonCodeStyleSettings.IndentOptions indentOptions,
                                                           FormattingDocumentModel documentModel,
                                                           int offset)