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

/**
 * 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));
    }
}
 

@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)) {

        final IRI transPropIri = (IRI) predVar.getValue();
        if (inferenceEngine.isTransitiveProperty(transPropIri)) {
            node.replaceWith(new TransitivePropertySP(sp.getSubjectVar(), sp.getPredicateVar(), sp.getObjectVar(), sp.getContextVar()));
        }
    }
}
 

@Override
protected double getCardinality(StatementPattern sp) {
    //always preffer HALYARD.SEARCH_TYPE object literals to move such statements higher in the joins tree
    Var objectVar = sp.getObjectVar();
    if (objectVar.hasValue() && (objectVar.getValue() instanceof Literal) && HALYARD.SEARCH_TYPE.equals(((Literal) objectVar.getValue()).getDatatype())) {
        return 0.0001;
    }
    Double card = spcalc == null ? null : spcalc.getCardinality(sp, boundVars);
    if (card == null) { //fallback to default cardinality calculation
        card = (hasValue(sp.getSubjectVar(), boundVars) ? 1.0 : 10.0) * (hasValue(sp.getPredicateVar(), boundVars) ? 1.0 : 10.0) * (hasValue(sp.getObjectVar(), boundVars) ? 1.0 : 10.0) * (hasValue(sp.getContextVar(), boundVars) ? 1.0 : 10.0);
    }
    for (Var v : sp.getVarList()) {
        //decrease cardinality for each priority variable present
        if (v != null && priorityVariables.contains(v.getName())) card /= 1000000.0;
    }
    return card;
}
 

/**
 * Constructs a {@link StatementPattern} from the StatementPatterns
 * representing a reified query. This StatementPattern has as a subject, the
 * object of the StatementPattern containing the predicate
 * {@link RDF#SUBJECT}. This StatementPattern has as predicate, the object
 * of the StatementPattern containing the predicate {@link RDF#PREDICATE}.
 * This StatementPattern has as an object, the object of the
 * StatementPattern containing the predicate {@link RDF#OBJECT}. This method
 * also builds a map between all predicates that are not of the above type
 * and the object {@link Var}s they are associated with. This map contains
 * the user specified metadata properties and is used for comparison with
 * the metadata properties extracted from RyaStatements passed back by the
 * {@link RyaQueryEngine}.
 *
 * @param patterns
 *            - collection of patterns representing a reified query
 */
private void setStatementPatternAndProperties(final Collection<StatementPattern> patterns) {

    final StatementPattern sp = new StatementPattern();
    final Map<RyaIRI, Var> properties = new HashMap<>();

    for (final StatementPattern pattern : patterns) {
        final RyaIRI predicate = new RyaIRI(pattern.getPredicateVar().getValue().toString());

        if (!uriList.contains(predicate)) {
            final Var objVar = pattern.getObjectVar();
            properties.put(predicate, objVar);
            continue;
        }

        if (predicate.equals(SUBJ_ID_URI)) {
            sp.setContextVar(pattern.getContextVar());
            sp.setSubjectVar(pattern.getObjectVar());
        }

        if (predicate.equals(PRED_ID_URI)) {
            sp.setPredicateVar(pattern.getObjectVar());
        }

        if (predicate.equals(OBJ_ID_URI)) {
            sp.setObjectVar(pattern.getObjectVar());
        }
    }
    this.statement = sp;
    this.properties = properties;
}
 

@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 symmPropIri = (IRI) predVar.getValue();
        if(inferenceEngine.isSymmetricProperty(symmPropIri)) {
            Var subjVar = sp.getSubjectVar();
            Union union = new InferUnion();
            union.setLeftArg(sp);
            union.setRightArg(new StatementPattern(objVar, predVar, subjVar, cntxtVar));
            node.replaceWith(union);
        }
    }
}
 

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 allValuesFrom 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>> relevantAvfRestrictions = inferenceEngine.getAllValuesFromByValueType(typeToInfer);
        if (!relevantAvfRestrictions.isEmpty()) {
            // We can infer the queried type if, for an allValuesFrom restriction type
            // associated  with the queried type, some anonymous neighboring node belongs to the
            // restriction type and has the node in question (subjVar) as a value for the
            // restriction's property.
            final Var avfTypeVar = new Var("t-" + UUID.randomUUID());
            final Var avfPredVar = 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), avfTypeVar);
            final StatementPattern valuePattern = new StatementPattern(neighborVar, avfPredVar, subjVar);
            final InferJoin avfPattern = new InferJoin(membershipPattern, valuePattern);
            // Use a FixedStatementPattern to contain the appropriate (restriction, predicate)
            // pairs, and check each one against the general pattern.
            final FixedStatementPattern avfPropertyTypes = new FixedStatementPattern(avfTypeVar,
                    new Var(OWL.ONPROPERTY.stringValue(), OWL.ONPROPERTY), avfPredVar);
            for (Resource avfRestrictionType : relevantAvfRestrictions.keySet()) {
                for (IRI avfProperty : relevantAvfRestrictions.get(avfRestrictionType)) {
                    avfPropertyTypes.statements.add(new NullableStatementImpl(avfRestrictionType,
                            OWL.ONPROPERTY, avfProperty));
                }
            }
            final InferJoin avfInferenceQuery = new InferJoin(avfPropertyTypes, avfPattern);
            node.replaceWith(new InferUnion(node.clone(), avfInferenceQuery));
        }
    }
}
 

/**
 * 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(final StatementPattern node) throws Exception {
    final StatementPattern currentNode = node.clone();
    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 && RDF.TYPE.equals(predVar.getValue()) && !EXPANDED.equals(conVar)) {
        final List<Set<Resource>> intersections = inferenceEngine.getIntersectionsImplying((IRI) objVar.getValue());
        if (intersections != null && !intersections.isEmpty()) {
            final List<TupleExpr> joins = new ArrayList<>();
            for (final Set<Resource> intersection : intersections) {
                final Set<Resource> sortedIntersection = new TreeSet<>(new ResourceComparator());
                sortedIntersection.addAll(intersection);

                // Create a join tree of all statement patterns in the
                // current intersection.
                final TupleExpr joinTree = createJoinTree(new ArrayList<>(sortedIntersection), subVar, conVar);
                if (joinTree != null) {
                    joins.add(joinTree);
                }
            }

            if (!joins.isEmpty()) {
                // Combine all the intersection join trees for the type
                // together into a union tree.  This will be a join tree if
                // only one intersection exists.
                final TupleExpr unionTree = createUnionTree(joins);
                // Union the above union tree of intersections with the
                // original node.
                final Union union = new InferUnion(unionTree, currentNode);
                node.replaceWith(union);
                log.trace("Replacing node with inferred intersection union: " + union);
            }
        }
    }
}
 

@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);
        }
    }
}
 

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();
}
 

/**
 * 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;
}
 

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

public ConstructProjection(StatementPattern pattern) {
    this(pattern.getSubjectVar(), pattern.getPredicateVar(), pattern.getObjectVar());
}
 

@Override
public void meet(StatementPattern node) throws RepositoryException {
	StringBuilder builder = new StringBuilder();
	Scope scope = node.getScope();
	Var subj = node.getSubjectVar();
	Var pred = node.getPredicateVar();
	Var obj = node.getObjectVar();
	Var ctx = node.getContextVar();
	boolean cokay = ctx == null && scope.equals(Scope.DEFAULT_CONTEXTS)
			|| ctx != null && scope.equals(Scope.NAMED_CONTEXTS);
	boolean sokay = !subj.hasValue() || subj.isAnonymous() || subj.getValue() instanceof IRI;
	boolean ookay = !obj.hasValue() || obj.isAnonymous() || obj.getValue() instanceof IRI
			|| obj.getValue() instanceof Literal;
	if (cokay && sokay && ookay) {
		variables.clear();
		if (ctx != null) {
			builder.append("GRAPH ");
			appendVar(builder, ctx.getName());
			builder.append(" {\n");
		}
		appendVar(builder, subj);
		appendVar(builder, pred);
		appendVar(builder, obj);
		builder.append(" .");
		appendFilter(builder, subj);
		appendFilter(builder, pred);
		appendFilter(builder, obj);
		if (ctx != null) {
			if (ctx.hasValue()) {
				builder.append("\nFILTER sameTerm(");
				appendVar(builder, ctx.getName());
				builder.append(", ");
				writeValue(builder, ctx.getValue());
				builder.append(")\n");
			}
			builder.append("}");
		}
		this.pattern = builder.toString();
		this.patternNode = node;
	} else {
		this.patternNode = null; // NOPMD
	}
}
 

private TupleExpr addList(List<? super Var> list, Var subj,
		Map<String, Map<IRI, List<StatementPattern>>> spIndex) {
	TupleExpr node = null;
	do {
		Map<IRI, List<StatementPattern>> predMap = spIndex.get(subj.getName());
		if (predMap == null) {
			return null;
		}

		List<StatementPattern> firstStmts = predMap.get(RDF.FIRST);
		if (firstStmts == null) {
			return null;
		}
		if (firstStmts.size() != 1) {
			return null;
		}

		List<StatementPattern> restStmts = predMap.get(RDF.REST);
		if (restStmts == null) {
			return null;
		}
		if (restStmts.size() != 1) {
			return null;
		}

		StatementPattern firstStmt = firstStmts.get(0);
		list.add(firstStmt.getObjectVar());
		node = join(node, firstStmt);

		StatementPattern restStmt = restStmts.get(0);
		subj = restStmt.getObjectVar();
		node = join(node, restStmt);

		List<StatementPattern> typeStmts = predMap.get(RDF.TYPE);
		if (typeStmts != null) {
			for (StatementPattern sp : firstStmts) {
				Value type = sp.getObjectVar().getValue();
				if (RDFS.RESOURCE.equals(type) || RDF.LIST.equals(type)) {
					node = join(node, sp);
				}
			}
		}
	} while (!RDF.NIL.equals(subj.getValue()));
	return node;
}
 

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());
}
 

private EventQueryNode getGeoTemporalNode(final Var subj) {
    final Collection<StatementPattern> patterns = patternMap.get(subj);
    final Collection<FunctionCall> usedFilters = new ArrayList<>();
    Optional<StatementPattern> geoPattern = Optional.empty();
    Optional<StatementPattern> temporalPattern = Optional.empty();
    Optional<Collection<IndexingExpr>> geoFilters = Optional.empty();
    Optional<Collection<IndexingExpr>> temporalFilters = Optional.empty();

    //should only be 2 patterns.
    for(final StatementPattern sp : patterns) {
        final Var obj = sp.getObjectVar();

        ///filter map does not have _const_


        if(filterMap.containsKey(obj)) {
            final Collection<IndexingExpr> filters = filterMap.get(obj);
            final IndexingFunctionRegistry.FUNCTION_TYPE type = ensureSameType(filters);
            if(type != null && type == FUNCTION_TYPE.GEO) {
                geoPattern = Optional.of(sp);
                geoFilters = Optional.of(filters);
                usedFilters.addAll(matchedFilters.get(obj));
            } else if(type != null && type == FUNCTION_TYPE.TEMPORAL) {
                temporalPattern = Optional.of(sp);
                temporalFilters = Optional.of(filters);
                usedFilters.addAll(matchedFilters.get(obj));
            } else {
                return null;
            }
        } else {
            return null;
        }
    }

    if(geoFilters.isPresent() && temporalFilters.isPresent() && geoPattern.isPresent() && temporalPattern.isPresent()) {
        return new EventQueryNodeBuilder()
                .setStorage(eventStorage)
                .setGeoPattern(geoPattern.get())
                .setTemporalPattern(temporalPattern.get())
                .setGeoFilters(geoFilters.get())
                .setTemporalFilters(temporalFilters.get())
                .setUsedFilters(usedFilters)
                .build();
    } else {
        return null;
    }
}
 

@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()));
//            }
        }
    }