{
    FeatureMapUtil.Validator validator = FeatureMapUtil.getValidator(owner.eClass(), feature);
    for (int i = 0, size = delegateSize(); i < size; ++i)
    {
      Entry entry = delegateGet(i);
      if (validator.isValid(entry.getEStructuralFeature()))
      {
        return false;
      }
    }
    return true;
  }