Java Code Examples for org.eclipse.rdf4j.query.algebra.StatementPattern#getSubjectVar()

/**
 * Check whether any solution for the {@link StatementPattern} could be derived from
 * reflexive property inference, and if so, replace the pattern with a union of itself and the
 * reflexive solution.
 */
@Override
protected void meetSP(StatementPattern node) throws Exception {
    // Only applies when the predicate is defined and reflexive
    final Var predVar = node.getPredicateVar();
    if (predVar.getValue() != null && inferenceEngine.isReflexiveProperty((IRI) predVar.getValue())) {
        final StatementPattern originalSP = node.clone();
        // The reflexive solution is a ZeroLengthPath between subject and
        // object: they can be matched to one another, whether constants or
        // variables.
        final Var subjVar = node.getSubjectVar();
        final Var objVar = node.getObjectVar();
        final ZeroLengthPath reflexiveSolution = new ZeroLengthPath(subjVar, objVar);
        node.replaceWith(new InferUnion(originalSP, reflexiveSolution));
    }
}
 

private Collection<FuzzyEntry<StatementPattern>> transformPattern(StatementPattern pattern)
{
    Set<FuzzyEntry<StatementPattern>> transformedPatterns = new HashSet<FuzzyEntry<StatementPattern>>();

    //queryTransformation.retrieveEquivalentURIs(pattern)
    Var sVar = pattern.getSubjectVar();
    Var pVar = pattern.getPredicateVar();
    Var oVar = pattern.getObjectVar();

    double patternProximity = 1.0;

    for (FuzzyEntry<Var> sVar1 : transformVar(sVar)) {
        for (FuzzyEntry<Var> pVar1 : transformVar(pVar)) {
            for (FuzzyEntry<Var> oVar1 : transformVar(oVar)) {
                StatementPattern p = new StatementPattern(sVar1.getElem(), pVar1.getElem(), oVar1.getElem());
                if (!p.equals(pattern)) {

                    double prox = Math.min(Math.min(sVar1.getProximity(), pVar1.getProximity()), oVar1.getProximity());
                    transformedPatterns.add(new FuzzyEntry<StatementPattern>(p, prox));
                }
            }
        }
    }

    return transformedPatterns;
}
 

private List<StatementPattern> replaceSameTermVars(List<StatementPattern> statementPatterns,
		Set<SameTerm> sameTermConstraints) {
	if (sameTermConstraints != null) {
		for (SameTerm st : sameTermConstraints) {
			Var left = (Var) st.getLeftArg();
			Var right = (Var) st.getRightArg();
			for (StatementPattern sp : statementPatterns) {
				Var subj = sp.getSubjectVar();
				Var obj = sp.getObjectVar();

				if (subj.equals(left) || subj.equals(right)) {
					if (obj.equals(left) || obj.equals(right)) {
						sp.setObjectVar(subj);
					}
				}
			}
		}
	}
	return statementPatterns;
}
 

/**
 * Provides a string representation of an SP which contains info about
 * whether each component (subj, pred, obj) is constant and its data and
 * data type if it is constant.
 *
 * @param sp - The statement pattern to convert. (not null)
 * @return A String representation of the statement pattern that may be
 *   used to do triple matching.
 */
public static String toStatementPatternString(final StatementPattern sp) {
    checkNotNull(sp);

    final Var subjVar = sp.getSubjectVar();
    String subj = subjVar.getName();
    if(subjVar.getValue() != null) {
        final Value subjValue = subjVar.getValue();
        subj = VarNameUtils.createSimpleConstVarName(subjVar);
        if (subjValue instanceof BNode ) {
            subj = subj + TYPE_DELIM + RyaSchema.BNODE_NAMESPACE + TYPE_DELIM + ((BNode) subjValue).getID();
        } else {
            subj = subj + TYPE_DELIM + URI_TYPE;
        }
    }

    final Var predVar = sp.getPredicateVar();
    String pred = predVar.getName();
    if(predVar.getValue() != null) {
        pred = VarNameUtils.createSimpleConstVarName(predVar);
        pred = pred + TYPE_DELIM + URI_TYPE;
    }

    final Var objVar = sp.getObjectVar();
    String obj = objVar.getName();
    if (objVar.getValue() != null) {
        final Value objValue = objVar.getValue();
        obj = VarNameUtils.createSimpleConstVarName(objVar);
        final RyaType rt = RdfToRyaConversions.convertValue(objValue);
        obj =  obj + TYPE_DELIM + rt.getDataType().stringValue();
    }

    return subj + DELIM + pred + DELIM + obj;
}
 

@Override
protected void meetSP(final StatementPattern node) throws Exception {
    final Var subVar = node.getSubjectVar();
    final Var predVar = node.getPredicateVar();
    final Var objVar = node.getObjectVar();
    final Var conVar = node.getContextVar();
    if (predVar != null && objVar != null && objVar.getValue() != null && objVar.getValue() instanceof Resource && RDF.TYPE.equals(predVar.getValue()) && !EXPANDED.equals(conVar)) {
        final Resource object = (Resource) objVar.getValue();
        if (inferenceEngine.isEnumeratedType(object)) {
            final Set<BindingSet> solutions = new LinkedHashSet<>();
            final Set<Resource> enumeration = inferenceEngine.getEnumeration(object);
            for (final Resource enumType : enumeration) {
                final QueryBindingSet qbs = new QueryBindingSet();
                qbs.addBinding(subVar.getName(), enumType);
                solutions.add(qbs);
            }

            if (!solutions.isEmpty()) {
                final BindingSetAssignment enumNode = new BindingSetAssignment();
                enumNode.setBindingSets(solutions);

                node.replaceWith(enumNode);
                log.trace("Replacing node with inferred one of enumeration: " + enumNode);
            }
        }
    }
}
 

private void processPropertySearches(final TupleExpr tupleExpr, final Collection<Var> searchProperties) {
    final MatchStatementVisitor matchStatements = new MatchStatementVisitor(searchProperties);
    tupleExpr.visit(matchStatements);
    for (final StatementPattern matchStatement: matchStatements.matchStatements) {
        final Var subject = matchStatement.getSubjectVar();
        if (subject.hasValue() && !(subject.getValue() instanceof Resource)) {
            throw new IllegalArgumentException("Query error: Found " + subject.getValue() + ", expected an IRI or BNode");
        }
        Validate.isTrue(subject.hasValue() || subject.getName() != null);
        Validate.isTrue(!matchStatement.getObjectVar().hasValue() && matchStatement.getObjectVar().getName() != null);
        buildQuery(tupleExpr, matchStatement);
    }
}
 

private void discoverPatterns(final StatementPattern pattern, final List<QueryModelNode> unmatched) {
    final Var subj = pattern.getSubjectVar();
    final Var objVar = pattern.getObjectVar();

    patternMap.put(subj, pattern);
    objectPatterns.put(objVar, pattern);
    //check for existing filters.
    if(unmatchedFilters.containsKey(objVar)) {
        final Collection<FunctionCall> calls = unmatchedFilters.removeAll(objVar);
        for(final FunctionCall call : calls) {
            addFilter(call);
            matchedFilters.put(objVar, call);
        }
    }
}
 

/**
 * Checks whether the StatementPattern is a type query whose solutions could be inferred by
 * someValuesFrom inference, and if so, replaces the node with a union of itself and any
 * possible inference.
 */
@Override
protected void meetSP(StatementPattern node) throws Exception {
    final Var subjVar = node.getSubjectVar();
    final Var predVar = node.getPredicateVar();
    final Var objVar = node.getObjectVar();
    // Only applies to type queries where the type is defined
    if (predVar != null && RDF.TYPE.equals(predVar.getValue()) && objVar != null && objVar.getValue() instanceof Resource) {
        final Resource typeToInfer = (Resource) objVar.getValue();
        Map<Resource, Set<IRI>> relevantSvfRestrictions = inferenceEngine.getSomeValuesFromByRestrictionType(typeToInfer);
        if (!relevantSvfRestrictions.isEmpty()) {
            // We can infer the queried type if it is to a someValuesFrom restriction (or a
            // supertype of one), and the node in question (subjVar) is the subject of a triple
            // whose predicate is the restriction's property and whose object is an arbitrary
            // node of the restriction's value type.
            final Var valueTypeVar = new Var("t-" + UUID.randomUUID());
            final Var svfPredVar = new Var("p-" + UUID.randomUUID());
            final Var neighborVar = new Var("n-" + UUID.randomUUID());
            neighborVar.setAnonymous(true);
            final StatementPattern membershipPattern = new DoNotExpandSP(neighborVar,
                    new Var(RDF.TYPE.stringValue(), RDF.TYPE), valueTypeVar);
            final StatementPattern valuePattern = new StatementPattern(subjVar, svfPredVar, neighborVar);
            final InferJoin svfPattern = new InferJoin(membershipPattern, valuePattern);
            // Use a FixedStatementPattern to contain the appropriate (predicate, value type)
            // pairs, and check each one against the general pattern.
            final FixedStatementPattern svfPropertyTypes = new FixedStatementPattern(svfPredVar,
                    new Var(OWL.SOMEVALUESFROM.stringValue(), OWL.SOMEVALUESFROM), valueTypeVar);
            for (Resource svfValueType : relevantSvfRestrictions.keySet()) {
                for (IRI svfProperty : relevantSvfRestrictions.get(svfValueType)) {
                    svfPropertyTypes.statements.add(new NullableStatementImpl(svfProperty,
                            OWL.SOMEVALUESFROM, svfValueType));
                }
            }
            final InferJoin svfInferenceQuery = new InferJoin(svfPropertyTypes, svfPattern);
            node.replaceWith(new InferUnion(node.clone(), svfInferenceQuery));
        }
    }
}
 

@Override
protected void meetSP(StatementPattern node) throws Exception {
    StatementPattern sp = node.clone();
    final Var predVar = sp.getPredicateVar();

    IRI pred = (IRI) predVar.getValue();
    String predNamespace = pred.getNamespace();

    final Var objVar = sp.getObjectVar();
    final Var cntxtVar = sp.getContextVar();
    if (objVar != null &&
            !RDF.NAMESPACE.equals(predNamespace) &&
            !SESAME.NAMESPACE.equals(predNamespace) &&
            !RDFS.NAMESPACE.equals(predNamespace)
            && !EXPANDED.equals(cntxtVar)) {
        /**
         *
         * { ?a ?pred ?b .}\n" +
         "       UNION " +
         "      { ?b ?pred ?a }
         */

        IRI predIri = (IRI) predVar.getValue();
        IRI invPropIri = inferenceEngine.findInverseOf(predIri);
        if (invPropIri != null) {
            Var subjVar = sp.getSubjectVar();
            Union union = new InferUnion();
            union.setLeftArg(sp);
            union.setRightArg(new StatementPattern(objVar, new Var(predVar.getName(), invPropIri), subjVar, cntxtVar));
            node.replaceWith(union);
        }
    }
}
 

private void processPropertySearches(final TupleExpr tupleExpr, final Collection<Var> searchProperties) {
    final MatchStatementVisitor matchStatements = new MatchStatementVisitor(searchProperties);
    tupleExpr.visit(matchStatements);
    for (final StatementPattern matchStatement: matchStatements.matchStatements) {
        final Var subject = matchStatement.getSubjectVar();
        if (subject.hasValue() && !(subject.getValue() instanceof Resource)) {
            throw new IllegalArgumentException("Query error: Found " + subject.getValue() + ", expected an IRI or BNode");
        }
        Validate.isTrue(subject.hasValue() || subject.getName() != null);
        Validate.isTrue(!matchStatement.getObjectVar().hasValue() && matchStatement.getObjectVar().getName() != null);
        buildQuery(tupleExpr, matchStatement);
    }
}
 

public FedXStatementPattern(StatementPattern node, QueryInfo queryInfo) {
	super(node.getSubjectVar(), node.getPredicateVar(), node.getObjectVar(), node.getContextVar());
	setScope(node.getScope());
	this.id = NodeFactory.getNextId();
	this.queryInfo = queryInfo;
	initFreeVars();
}
 

@Override
    protected void meetSP(final StatementPattern node) throws Exception {
        final StatementPattern sp = node.clone();
        final Var predVar = sp.getPredicateVar();

        final IRI pred = (IRI) predVar.getValue();
        final String predNamespace = pred.getNamespace();

        final Var objVar = sp.getObjectVar();
        final Var cntxtVar = sp.getContextVar();
        if (objVar != null &&
                !RDF.NAMESPACE.equals(predNamespace) &&
                !SESAME.NAMESPACE.equals(predNamespace) &&
                !RDFS.NAMESPACE.equals(predNamespace)
                && !EXPANDED.equals(cntxtVar)) {
            /**
             *
             * { ?subProp rdfs:subPropertyOf ub:worksFor . ?y ?subProp <http://www.Department0.University0.edu> }\n" +
             "       UNION " +
             "      { ?y ub:worksFor <http://www.Department0.University0.edu> }
             */
//            String s = UUID.randomUUID().toString();
//            Var subPropVar = new Var(s);
//            StatementPattern subPropOf = new StatementPattern(subPropVar, new Var("c-" + s, SESAME.DIRECTSUBPROPERTYOF), predVar, EXPANDED);
//            StatementPattern subPropOf2 = new StatementPattern(sp.getSubjectVar(), subPropVar, objVar, EXPANDED);
//            InferJoin join = new InferJoin(subPropOf, subPropOf2);
//            join.getProperties().put(InferConstants.INFERRED, InferConstants.TRUE);
//            node.replaceWith(join);

//            Collection<URI> parents = inferenceEngine.findParents(inferenceEngine.subPropertyOfGraph, (URI) predVar.getValue());
//            if (parents != null && parents.size() > 0) {
//                StatementPatterns statementPatterns = new StatementPatterns();
//                statementPatterns.patterns.add(node);
//                Var subjVar = node.getSubjectVar();
//                for (IRI iri : parents) {
//                    statementPatterns.patterns.add(new StatementPattern(subjVar, new Var(predVar.getName(), iri), objVar));
//                }
//                node.replaceWith(statementPatterns);
//            }
//            if (parents != null && parents.size() > 0) {
//                VarCollection vc = new VarCollection();
//                vc.setName(predVar.getName());
//                vc.values.add(predVar);
//                for (IRI iri : parents) {
//                    vc.values.add(new Var(predVar.getName(), iri));
//                }
//                Var subjVar = node.getSubjectVar();
//                node.replaceWith(new StatementPattern(subjVar, vc, objVar, node.getContextVar()));
//            }

            final IRI subprop_iri = (IRI) predVar.getValue();
            final Set<IRI> parents = InferenceEngine.findParents(inferenceEngine.getSubPropertyOfGraph(), subprop_iri);
            if (parents != null && parents.size() > 0) {
                final String s = UUID.randomUUID().toString();
                final Var typeVar = new Var(s);
                final FixedStatementPattern fsp = new FixedStatementPattern(typeVar, new Var("c-" + s, RDFS.SUBPROPERTYOF), predVar, cntxtVar);
//                fsp.statements.add(new NullableStatementImpl(subprop_uri, RDFS.SUBPROPERTYOF, subprop_uri));
                //add self
                parents.add(subprop_iri);
                for (final IRI u : parents) {
                    fsp.statements.add(new NullableStatementImpl(u, RDFS.SUBPROPERTYOF, subprop_iri));
                }

                final StatementPattern rdfType = new DoNotExpandSP(sp.getSubjectVar(), typeVar, sp.getObjectVar(), cntxtVar);
                final InferJoin join = new InferJoin(fsp, rdfType);
                join.getProperties().put(InferConstants.INFERRED, InferConstants.TRUE);
                node.replaceWith(join);
            }
        }
    }
 

public TrueStatementPattern(StatementPattern node) {
	super(node.getSubjectVar(), node.getPredicateVar(), node.getObjectVar(), node.getContextVar());
}
 

public EmptyStatementPattern(StatementPattern node) {
	super(node.getSubjectVar(), node.getPredicateVar(), node.getObjectVar(), node.getContextVar());
}
 

/**
 * Checks whether facts matching the StatementPattern could be derived using
 * has-value inference, and if so, replaces the StatementPattern node with a
 * union of itself and any such possible derivations.
 */
@Override
protected void meetSP(StatementPattern node) throws Exception {
    final Var subjVar = node.getSubjectVar();
    final Var predVar = node.getPredicateVar();
    final Var objVar = node.getObjectVar();
    // We can reason over two types of statement patterns:
    // { ?var rdf:type :Restriction } and { ?var :property ?value }
    // Both require defined predicate
    if (predVar != null && predVar.getValue() != null) {
        final IRI predIRI = (IRI) predVar.getValue();
        if (RDF.TYPE.equals(predIRI) && objVar != null && objVar.getValue() != null
                && objVar.getValue() instanceof Resource) {
            // If the predicate is rdf:type and the type is specified, check whether it can be
            // inferred using any hasValue restriction(s)
            final Resource objType = (Resource) objVar.getValue();
            final Map<IRI, Set<Value>> sufficientValues = inferenceEngine.getHasValueByType(objType);
            if (sufficientValues.size() > 0) {
                final Var valueVar = new Var("v-" + UUID.randomUUID());
                TupleExpr currentNode = node.clone();
                for (IRI property : sufficientValues.keySet()) {
                    final Var propVar = new Var(property.toString(), property);
                    final TupleExpr valueSP = new DoNotExpandSP(subjVar, propVar, valueVar);
                    final FixedStatementPattern relevantValues = new FixedStatementPattern(objVar, propVar, valueVar);
                    for (Value value : sufficientValues.get(property)) {
                        relevantValues.statements.add(new NullableStatementImpl(objType, property, value));
                    }
                    currentNode = new InferUnion(currentNode, new InferJoin(relevantValues, valueSP));
                }
                node.replaceWith(currentNode);
            }
        }
        else {
            // If the predicate has some hasValue restriction associated with it, then finding
            // that the object belongs to the appropriate type implies a value.
            final Map<Resource, Set<Value>> impliedValues = inferenceEngine.getHasValueByProperty(predIRI);
            if (impliedValues.size() > 0) {
                final Var rdfTypeVar = new Var(RDF.TYPE.stringValue(), RDF.TYPE);
                final Var typeVar = new Var("t-" + UUID.randomUUID());
                final Var hasValueVar = new Var(OWL.HASVALUE.stringValue(), OWL.HASVALUE);
                final TupleExpr typeSP = new DoNotExpandSP(subjVar, rdfTypeVar, typeVar);
                final FixedStatementPattern typeToValue = new FixedStatementPattern(typeVar, hasValueVar, objVar);
                final TupleExpr directValueSP = node.clone();
                for (Resource type : impliedValues.keySet()) {
                    // { ?var rdf:type :type } implies { ?var :property :val } for certain (:type, :val) pairs
                    for (Value impliedValue : impliedValues.get(type)) {
                        typeToValue.statements.add(new NullableStatementImpl(type, OWL.HASVALUE, impliedValue));
                    }
                }
                node.replaceWith(new InferUnion(new InferJoin(typeToValue, typeSP), directValueSP));
            }
        }
    }
}
 

@Override
    protected void meetSP(final StatementPattern node) throws Exception {
        final StatementPattern sp = node.clone();
        final Var predVar = sp.getPredicateVar();
        final Var objVar = sp.getObjectVar();
        final Var conVar = sp.getContextVar();
        if (predVar != null && objVar != null && objVar.getValue() != null && RDF.TYPE.equals(predVar.getValue())
                && !EXPANDED.equals(conVar)) {
            /**
             * ?type sesame:directSubClassOf ub:Student . ?student rdf:type ?type +
             */
//            String s = UUID.randomUUID().toString();
//            Var typeVar = new Var(s);
//            StatementPattern subClassOf = new StatementPattern(typeVar, new Var("c-" + s, SESAME.DIRECTSUBCLASSOF), objVar, SUBCLASS_EXPANDED);
//            StatementPattern rdfType = new StatementPattern(sp.getSubjectVar(), sp.getPredicateVar(), typeVar, SUBCLASS_EXPANDED);
//            InferJoin join = new InferJoin(subClassOf, rdfType);
//            join.getProperties().put(InferConstants.INFERRED, InferConstants.TRUE);
//            node.replaceWith(join);

            final IRI subclassof_iri = (IRI) objVar.getValue();
            final Collection<IRI> parents = InferenceEngine.findParents(inferenceEngine.getSubClassOfGraph(), subclassof_iri);
            if (parents != null && parents.size() > 0) {
                final String s = UUID.randomUUID().toString();
                final Var typeVar = new Var(s);
                final FixedStatementPattern fsp = new FixedStatementPattern(typeVar, new Var("c-" + s, RDFS.SUBCLASSOF), objVar, conVar);
                parents.add(subclassof_iri);
                for (final IRI iri : parents) {
                    fsp.statements.add(new NullableStatementImpl(iri, RDFS.SUBCLASSOF, subclassof_iri));
                }

                final StatementPattern rdfType = new DoNotExpandSP(sp.getSubjectVar(), sp.getPredicateVar(), typeVar, conVar);
                final InferJoin join = new InferJoin(fsp, rdfType);
                join.getProperties().put(InferConstants.INFERRED, InferConstants.TRUE);
                node.replaceWith(join);
            }

//            if (parents != null && parents.size() > 0) {
//                StatementPatterns statementPatterns = new StatementPatterns();
//                statementPatterns.patterns.add(node);
//                Var subjVar = node.getSubjectVar();
//                for (IRI iri : parents) {
//                    statementPatterns.patterns.add(new StatementPattern(subjVar, predVar, new Var(objVar.getName(), iri)));
//                }
//                node.replaceWith(statementPatterns);
//            }

//            if (parents != null && parents.size() > 0) {
//                VarCollection vc = new VarCollection();
//                vc.setName(objVar.getName());
//                vc.values.add(objVar);
//                for (IRI iri : parents) {
//                    vc.values.add(new Var(objVar.getName(), iri));
//                }
//                Var subjVar = node.getSubjectVar();
//                node.replaceWith(new StatementPattern(subjVar, predVar, vc, node.getContextVar()));
//            }
        }
    }
 

public FedXStatementPattern(StatementPattern node, QueryInfo queryInfo) {
	super(node.getSubjectVar(), node.getPredicateVar(), node.getObjectVar(), node.getContextVar());
	this.id = NodeFactory.getNextId();
	this.queryInfo=queryInfo;
	initFreeVars();
}
 

public TrueStatementPattern(StatementPattern node) {
	super(node.getSubjectVar(), node.getPredicateVar(), node.getObjectVar(), node.getContextVar());
}
 

private Var getTypeSubject(final Type type) {
    //we just need the first pattern since all the patterns in this type map are the same subject
    final StatementPattern pattern = typeMap.get(type).iterator().next();
    return pattern.getSubjectVar();
}
 

public EmptyStatementPattern(StatementPattern node) {
	super(node.getSubjectVar(), node.getPredicateVar(), node.getObjectVar(), node.getContextVar());
}