@Override
  public void validate(@NotNull PsiElement context, @NotNull final ValidationHost host) {
    final XmlDocument doc = PsiTreeUtil.getContextOfType(context, XmlDocument.class, false);
    if (doc == null) {
      return;
    }
    final XmlTag rootTag = doc.getRootTag();
    if (rootTag == null) {
      return;
    }
    // RNG XML itself is validated by parsing it with Jing, so we don't want to schema-validate it
    if (!RelaxNgMetaDataContributor.RNG_NAMESPACE.equals(rootTag.getNamespace())) {
      XmlInstanceValidator.doValidation(doc, host, getDescriptorFile());
    }
  }
@Override
  public void validate(@NotNull PsiElement context, @NotNull final ValidationHost host)