/**
* Answer a list of the named hierarchy roots of a given {@link OntModel}. This will be similar to
* the results of {@link OntModel#listHierarchyRootClasses()}, with the added constraint that
* every member of the returned iterator will be a named class, not an anonymous class expression.
* The named root classes are calculated from the root classes, by recursively replacing every
* anonymous class with its direct sub-classes. Thus it can be seen that the values in the list
* consists of the shallowest fringe of named classes in the hierarchy.
*
* @param m An ontology model
* @return A list of classes whose members are the named root classes of the class hierarchy in
* <code>m</code>
*/
public static List<OntClass> namedHierarchyRoots(OntModel m) {
List<OntClass> nhr = new ArrayList<OntClass>(); // named roots
List<OntClass> ahr = new ArrayList<OntClass>(); // anon roots
// do the initial partition of the root classes
partitionByNamed(m.listHierarchyRootClasses(), nhr, ahr);
// now push the fringe down until we have only named classes
while (!ahr.isEmpty()) {
OntClass c = ahr.remove(0);
partitionByNamed(c.listSubClasses(true), nhr, ahr);
}
return nhr;
}
