class GcsFileSystemRegistrar implements FileSystemRegistrar {

  @Override
  public Iterable<FileSystem> fromOptions(@Nonnull PipelineOptions options) {
    checkNotNull(options, "Expect the runner have called FileSystems.setDefaultPipelineOptions().");
    return ImmutableList.of(new GcsFileSystem(options.as(GcsOptions.class)));
  }

}