private static @Nullable DomElementProblemDescriptor checkRequiredGenericValue(final GenericDomValue child, final Required required,
                                                                                 final DomElementAnnotationHolder annotator) {
    final String stringValue = child.getStringValue();
    if (stringValue == null) return null;

    if (required.nonEmpty() && isEmpty(child, stringValue)) {
      return annotator.createProblem(child, XmlDomBundle.message("dom.inspections.value.must.not.be.empty"));
    }
    if (required.identifier() && !isIdentifier(stringValue)) {
      return annotator.createProblem(child, XmlDomBundle.message("dom.inspections.value.must.be.identifier"));
    }
    return null;
  }
private static @Nullable DomElementProblemDescriptor checkRequiredGenericValue(final GenericDomValue child, final Required required,
                                                                                 final DomElementAnnotationHolder annotator)