@Nullable
  private static Artifacts deserialize(@Nullable URL url) {
    if (url == null) return null;

    Artifacts allArtifacts = null;
    try {
      allArtifacts = XmlSerializer.deserialize(url, Artifacts.class);
    }
    catch (SerializationException e) {
      final Throwable cause = e.getCause();
      if (!(cause instanceof IOException)) {
        LOG.error(e);
      }
    }
    return allArtifacts;
  }
@Nullable
  private static Artifacts deserialize(@Nullable URL url)