@Override
  public Map<String, Integer> getCounts() {
    return new ImmutableMap.Builder<String, Integer>()
        .put(PHOTOS_COUNT_DATA_NAME, photos.size())
        .put(ALBUMS_COUNT_DATA_NAME, albums.size())
        .build();
  }
A Wrapper for all the possible objects that can be returned by a photos exporter.
portability-types-common/src/main/java/org/datatransferproject/types/common/models/photos/PhotosContainerResource.java