@Nullable
  private static String getFileName(@Nullable Editor editor, VirtualFile @Nullable [] files) {
    if (files != null && files.length == 1 && !files[0].isDirectory()) {
      return files[0].getName();
    }
    if (editor != null) {
      return "";
    }
    return null;
  }
@Nullable
  private static String getFileName(@Nullable Editor editor, VirtualFile @Nullable [] files)