@Override
  public @Nullable XmlElementDescriptor getElementDescriptor(String localName,
                                                             String namespace,
                                                             Set<? super XmlNSDescriptorImpl> visited,
                                                             boolean reference) {
    return getFirst(descriptor -> descriptor.getElementDescriptor(localName, namespace, visited, reference));
  }
@Override
  public @Nullable XmlElementDescriptor getElementDescriptor(String localName,
                                                             String namespace,
                                                             Set<? super XmlNSDescriptorImpl> visited,
                                                             boolean reference)