@Nullable
  private static MavenRepositoryModel readRepositoryModel(final IonReader reader, ReadContext context) {
    if (reader.next() == null) return null;
    reader.stepIn();
    MavenRepositoryModel dependency =
      context.repositoryMap.computeIfAbsent(readInt(reader, OBJECT_ID_FIELD), new SimpleObjectFactory<MavenRepositoryModel>() {
        @Override
        public MavenRepositoryModel create() {
          return new MavenRepositoryModelImpl(readString(reader, "name"), readString(reader, "url"));
        }
      });
    reader.stepOut();
    return dependency;
  }
@Nullable
  private static MavenRepositoryModel readRepositoryModel(final IonReader reader, ReadContext context)