return dataPropertyHierarchyNodesToNodeSet(result);
}
else {
OWLDataFactory factory=getDataFactory();
if (propertyExpression.isOWLTopDataProperty() && isConsistent())
return new OWLDataPropertyNodeSet(new OWLDataPropertyNode(factory.getOWLBottomDataProperty()));
else if (propertyExpression.isOWLBottomDataProperty() && isConsistent())
return new OWLDataPropertyNodeSet(new OWLDataPropertyNode(factory.getOWLTopDataProperty()));
else
return new OWLDataPropertyNodeSet();
}
}