List<ClassTree> parents = new ArrayList<ClassTree>();
for (FilterMapping mapping : filterMappings) {
if (mapping.getInheritedFromClass() != null) {
root = determineRootInternal(root, parents, mapping.getInheritedFromClass());
if (root == null) {
throw new NoPossibleResultsException("AND filter on different class hierarchies produces no results");
}
}
}
for (Class<?> clazz : polyEntities) {