class GcsResourceId implements ResourceId {

  @Override
  @Nullable public String getFilename() {
    if (gcsPath.getNameCount() <= 1) {
      return null;
    } else {
      GcsPath gcsFilename = gcsPath.getFileName();
      return gcsFilename == null ? null : gcsFilename.toString();
    }
  }

  private  GcsResourceId(GcsPath gcsPath);

}