private @Nullable Object getSlowData(@NotNull String dataId, VirtualFile @NotNull [] selectedFiles) {
    if (CommonDataKeys.PSI_FILE.is(dataId)) {
      return getData(CommonDataKeys.PSI_ELEMENT.getName());
    }
    else if (CommonDataKeys.PSI_ELEMENT.is(dataId)) {
      return selectedFiles.length > 0 ? PsiManager.getInstance(thumbnailView.getProject()).findFile(selectedFiles[0]) : null;
    }
    else if (PlatformCoreDataKeys.PSI_ELEMENT_ARRAY.is(dataId)) {
      return getSelectedElements();
    }
    return null;
  }
private @Nullable Object getSlowData(@NotNull String dataId, VirtualFile @NotNull [] selectedFiles)