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HermiT is reasoner for ontologies written using the Web Ontology Language (OWL). Given an OWL file, HermiT can determine whether or not the ontology is consistent, identify subsumption relationships between classes, and much more.
This is the maven build of HermiT and is designed for people who wish to use HermiT from within the OWL API. It is now versioned in the main HermiT version repository, although not officially supported by the HermiT developers.
The version number of this package is a composite of the HermiT version and a value representing the OWLAPI release it is compatible with. Note that the group id for the upstream HermiT is com.hermit-reasoner, while this fork is released under net.sourceforge.owlapi.
This fork exists to allow HermiT users to use newer OWLAPI versions than the ones supported by the original HermiT codebase.
This package includes the Jautomata library (http://jautomata.sourceforge.net/), and builds with it directly. This library appears to be no longer under active development, and so a "fork" seems appropriate. No development is intended or anticipated on this code base.
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/* Copyright 2009 by the Oxford University Computing Laboratory
This file is part of HermiT.
HermiT is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
HermiT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with HermiT. If not, see m_elements;
/**
* @param tableau tableau
* @param progressMonitor progressMonitor
* @param topElement topElement
* @param bottomElement bottomElement
* @param elements elements
*/
public DeterministicClassification(Tableau tableau,ClassificationProgressMonitor progressMonitor,AtomicConcept topElement,AtomicConcept bottomElement,Set elements) {
m_tableau=tableau;
m_progressMonitor=progressMonitor;
m_topElement=topElement;
m_bottomElement=bottomElement;
m_elements=elements;
}
/**
* @return hierarchy
*/
public Hierarchy classify() {
if (!m_tableau.isDeterministic())
throw new IllegalStateException("Internal error: DeterministicClassificationManager can be used only with a deterministic tableau.");
Individual freshIndividual=Individual.createAnonymous("fresh-individual");
if (!m_tableau.isSatisfiable(true,Collections.singleton(Atom.create(m_topElement,freshIndividual)),null,null,null,null,ReasoningTaskDescription.isConceptSatisfiable(m_topElement)))
return Hierarchy.emptyHierarchy(m_elements,m_topElement,m_bottomElement);
Map> allSubsumers=new HashMap<>();
for (AtomicConcept element : m_elements) {
Set subsumers;
Map nodesForIndividuals=new HashMap<>();
nodesForIndividuals.put(freshIndividual,null);
if (!m_tableau.isSatisfiable(true,Collections.singleton(Atom.create(element,freshIndividual)),null,null,null,nodesForIndividuals,ReasoningTaskDescription.isConceptSatisfiable(element)))
subsumers=m_elements;
else {
subsumers=new HashSet<>();
subsumers.add(m_topElement);
ExtensionTable.Retrieval retrieval=m_tableau.getExtensionManager().getBinaryExtensionTable().createRetrieval(new boolean[] { false,true },ExtensionTable.View.TOTAL);
retrieval.getBindingsBuffer()[1]=nodesForIndividuals.get(freshIndividual).getCanonicalNode();
retrieval.open();
while (!retrieval.afterLast()) {
Object subsumer=retrieval.getTupleBuffer()[0];
if (subsumer instanceof AtomicConcept && m_elements.contains(subsumer))
subsumers.add((AtomicConcept)subsumer);
retrieval.next();
}
}
allSubsumers.put(element,new GraphNode<>(element,subsumers));
m_progressMonitor.elementClassified(element);
}
return buildHierarchy(m_topElement,m_bottomElement,allSubsumers);
}
/**
* @param topElement topElement
* @param bottomElement bottomElement
* @param graphNodes graphNodes
* @param type
* @return hierarchy
*/
public static Hierarchy buildHierarchy(T topElement,T bottomElement,Map> graphNodes) {
HierarchyNode topNode=new HierarchyNode<>(topElement);
HierarchyNode bottomNode=new HierarchyNode<>(bottomElement);
Hierarchy hierarchy=new Hierarchy<>(topNode,bottomNode);
// Compute SCCs (strongly connected components), create hierarchy nodes, and topologically order them
List> topologicalOrder=new ArrayList<>();
visit(new Stack>(),new DFSIndex(),graphNodes,graphNodes.get(bottomElement),hierarchy,topologicalOrder);
// Process the nodes in the topological order
Map,Set>> reachableFrom=new HashMap<>();
List> allSuccessors=new ArrayList<>();
for (int index=0;index node=topologicalOrder.get(index);
Set> reachableFromNode=new HashSet<>();
reachableFromNode.add(node);
reachableFrom.put(node,reachableFromNode);
allSuccessors.clear();
for (T element : node.m_equivalentElements) {
GraphNode graphNode=graphNodes.get(element);
for (T successor : graphNode.m_successors) {
GraphNode successorGraphNode=graphNodes.get(successor);
if (successorGraphNode!=null)
allSuccessors.add(successorGraphNode);
}
}
Collections.sort(allSuccessors);
for (int successorIndex=allSuccessors.size()-1;successorIndex>=0;--successorIndex) {
GraphNode successorGraphNode=allSuccessors.get(successorIndex);
HierarchyNode successorNode=hierarchy.m_nodesByElements.get(successorGraphNode.m_element);
if (!reachableFromNode.contains(successorNode)) {
node.m_parentNodes.add(successorNode);
successorNode.m_childNodes.add(node);
reachableFromNode.add(successorNode);
reachableFromNode.addAll(reachableFrom.get(successorNode));
}
}
}
return hierarchy;
}
protected static void visit(Stack> stack,DFSIndex dfsIndex,Map> graphNodes,GraphNode graphNode,Hierarchy hierarchy,List> topologicalOrder) {
graphNode.m_dfsIndex=dfsIndex.m_value++;
graphNode.m_SCChead=graphNode;
stack.push(graphNode);
for (T successor : graphNode.m_successors) {
GraphNode successorGraphNode=graphNodes.get(successor);
if (successorGraphNode!=null) {
if (successorGraphNode.notVisited())
visit(stack,dfsIndex,graphNodes,successorGraphNode,hierarchy,topologicalOrder);
if (!successorGraphNode.isAssignedToSCC() && successorGraphNode.m_SCChead.m_dfsIndex equivalentElements=new HashSet<>();
GraphNode poppedNode;
do {
poppedNode=stack.pop();
poppedNode.m_topologicalOrderIndex=nextTopologicalOrderIndex;
equivalentElements.add(poppedNode.m_element);
} while (poppedNode!=graphNode);
HierarchyNode hierarchyNode;
if (equivalentElements.contains(hierarchy.getTopNode().m_representative))
hierarchyNode=hierarchy.getTopNode();
else if (equivalentElements.contains(hierarchy.getBottomNode().m_representative))
hierarchyNode=hierarchy.getBottomNode();
else
hierarchyNode=new HierarchyNode<>(graphNode.m_element);
for (T element : equivalentElements) {
hierarchyNode.m_equivalentElements.add(element);
hierarchy.m_nodesByElements.put(element,hierarchyNode);
}
topologicalOrder.add(hierarchyNode);
}
}
static class GraphNode implements Comparable> {
public final T m_element;
public final Set m_successors;
public int m_dfsIndex;
public GraphNode m_SCChead;
public int m_topologicalOrderIndex;
public GraphNode(T element,Set successors) {
m_element=element;
m_successors=successors;
m_dfsIndex=-1;
m_SCChead=null;
m_topologicalOrderIndex=-1;
}
public boolean notVisited() {
return m_dfsIndex==-1;
}
public boolean isAssignedToSCC() {
return m_topologicalOrderIndex!=-1;
}
@Override
public int compareTo(GraphNode o) {
return m_topologicalOrderIndex-o.m_topologicalOrderIndex;
}
}
protected static class DFSIndex {
public int m_value;
}
}