private static void addToPsiFileList(PsiDirectory psiDirectory, List<? super PsiFile> filesList, boolean isRecursive) {
    PsiFile[] files = psiDirectory.getFiles();
    Collections.addAll(filesList, files);
    if (isRecursive) {
      for (PsiDirectory directory : psiDirectory.getSubdirectories()) {
        if (!Project.DIRECTORY_STORE_FOLDER.equals(directory.getName())) {
          addToPsiFileList(directory, filesList, true);
        }
      }
    }
  }
private static void addToPsiFileList(PsiDirectory psiDirectory, List<? super PsiFile> filesList, boolean isRecursive)