org.semanticweb.HermiT.datalog.DatalogEngine Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of org.semanticweb.hermit Show documentation

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 an value representing releases of this packaged version. So, 1.3.7.1 is the first release of the mavenized version of HermiT based on the 1.3.7 release of HermiT. 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.

There is a newer version: 1.3.8.4

Show newest version

package org.semanticweb.HermiT.datalog;

import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.semanticweb.HermiT.existentials.ExistentialExpansionStrategy;
import org.semanticweb.HermiT.model.Atom;
import org.semanticweb.HermiT.model.AtomicRole;
import org.semanticweb.HermiT.model.Concept;
import org.semanticweb.HermiT.model.DLClause;
import org.semanticweb.HermiT.model.DLOntology;
import org.semanticweb.HermiT.model.DataRange;
import org.semanticweb.HermiT.model.Term;
import org.semanticweb.HermiT.model.Variable;
import org.semanticweb.HermiT.tableau.DLClauseEvaluator;
import org.semanticweb.HermiT.tableau.ExtensionManager;
import org.semanticweb.HermiT.tableau.InterruptFlag;
import org.semanticweb.HermiT.tableau.Node;
import org.semanticweb.HermiT.tableau.Tableau;

public final class DatalogEngine {
    protected final InterruptFlag m_interruptFlag;
    protected final DLOntology m_dlOntology;
    protected final Map m_termsToNodes;
    protected final Map m_nodesToTerms;
    protected final Map> m_termsToEquivalenceClasses;
    protected final Map m_termsToRepresentatives;
    protected ExtensionManager m_extensionManager;
    
    public DatalogEngine(DLOntology dlOntology) {
        for (DLClause dlClause : dlOntology.getDLClauses())
            if (dlClause.getHeadLength()>1)
                throw new IllegalArgumentException("The supplied DL ontology contains rules with disjunctive heads.");
        m_interruptFlag=new InterruptFlag(0);
        m_dlOntology=dlOntology;
        m_termsToNodes=new HashMap();
        m_nodesToTerms=new HashMap();
        m_termsToEquivalenceClasses=new HashMap>();
        m_termsToRepresentatives=new HashMap();
    }
    public void interrupt() {
        m_interruptFlag.interrupt();
    }
    public boolean materialize() {
        if (m_extensionManager==null) {
            m_termsToNodes.clear();
            m_nodesToTerms.clear();
            m_termsToEquivalenceClasses.clear();
            m_termsToRepresentatives.clear();
            Tableau tableau=new Tableau(m_interruptFlag,null,NullExistentialExpansionStrategy.INSTANCE,false,m_dlOntology,null,new HashMap());
            Set noAtoms=Collections.emptySet();
            tableau.isSatisfiable(true,false,noAtoms,noAtoms,noAtoms,noAtoms,m_termsToNodes,null,null);
            for (Map.Entry entry : m_termsToNodes.entrySet())
                m_nodesToTerms.put(entry.getValue(),entry.getKey());
            m_extensionManager=tableau.getExtensionManager();
            Node node=tableau.getFirstTableauNode();
            while (node!=null) {
                Term term=m_nodesToTerms.get(node);
                Term canonicalTerm=m_nodesToTerms.get(node.getCanonicalNode());
                Set equivalenceClass=m_termsToEquivalenceClasses.get(canonicalTerm);
                if (equivalenceClass==null) {
                    equivalenceClass=new HashSet();
                    m_termsToEquivalenceClasses.put(canonicalTerm,equivalenceClass);
                }
                if (!term.equals(canonicalTerm))
                    m_termsToEquivalenceClasses.put(term,equivalenceClass);
                equivalenceClass.add(term);
                m_termsToRepresentatives.put(term,canonicalTerm);
                node=node.getNextTableauNode();
            }
        }
        return !m_extensionManager.containsClash();
    }
    public DLOntology getDLOntology() {
        return m_dlOntology;
    }
    public Set getEquivalenceClass(Term term) {
        return m_termsToEquivalenceClasses.get(term);
    }
    public Term getRepresentative(Term term) {
        return m_termsToRepresentatives.get(term);
    }
    
    protected static class NullExistentialExpansionStrategy implements ExistentialExpansionStrategy {
        public static final ExistentialExpansionStrategy INSTANCE=new NullExistentialExpansionStrategy();

        public void initialize(Tableau tableau) {
        }
        public void additionalDLOntologySet(DLOntology additionalDLOntology) {
        }
        public void additionalDLOntologyCleared() {
        }
        public void clear() {
        }
        public boolean expandExistentials(boolean finalChance) {
            return false;
        }
        public void assertionAdded(Concept concept,Node node,boolean isCore) {
        }
        public void assertionAdded(DataRange dataRange,Node node,boolean isCore) {
        }
        public void assertionCoreSet(Concept concept,Node node) {
        }
        public void assertionCoreSet(DataRange dataRange,Node node) {
        }
        public void assertionRemoved(Concept concept,Node node,boolean isCore) {
        }
        public void assertionRemoved(DataRange dataRange,Node node,boolean isCore) {
        }
        public void assertionAdded(AtomicRole atomicRole,Node nodeFrom,Node nodeTo,boolean isCore) {
        }
        public void assertionCoreSet(AtomicRole atomicRole,Node nodeFrom,Node nodeTo) {
        }
        public void assertionRemoved(AtomicRole atomicRole,Node nodeFrom,Node nodeTo,boolean isCore) {
        }
        public void nodesMerged(Node mergeFrom,Node mergeInto) {
        }
        public void nodesUnmerged(Node mergeFrom,Node mergeInto) {
        }
        public void nodeStatusChanged(Node node) {
        }
        public void nodeInitialized(Node node) {
        }
        public void nodeDestroyed(Node node) {
        }
        public void branchingPointPushed() {
        }
        public void backtrack() {
        }
        public void modelFound() {
        }
        public boolean isDeterministic() {
            return true;
        }
        public boolean isExact() {
            return true;
        }
        public void dlClauseBodyCompiled(List workers,DLClause dlClause,List variables,Object[] valuesBuffer,boolean[] coreVariables) {
        }
    }
}