filterMapping.setDirectFilterValues(new EmptyFilterValues());
// Handle special values on a case by case basis
List<String> specialValues = fasc.getSpecialFilterValues();
if (specialValues.contains(FilterAndSortCriteria.IS_NULL_FILTER_VALUE)) {
filterMapping.setRestriction(new Restriction().withPredicateProvider(new IsNullPredicateProvider()));
}
if (specialValues.contains(FilterAndSortCriteria.IS_NOT_NULL_FILTER_VALUE)) {
filterMapping.setRestriction(new Restriction().withPredicateProvider(new IsNotNullPredicateProvider()));
}
} else {