@Nullable
    @Override
    public Object getData(@NotNull String dataId) {
      if (CommonDataKeys.VIRTUAL_FILE.is(dataId)) {
        return myDir;
      }
      if (PlatformCoreDataKeys.BGT_DATA_PROVIDER.is(dataId)) {
        return (DataProvider)slowId -> getSlowData(slowId);
      }
      return null;
    }
@Nullable
    @Override
    public Object getData(@NotNull String dataId)