Examples with NullableStatementImpl org.apache.rya.api.utils.NullableStatementImpl used on opensource projects

Example 11 with NullableStatementImpl

use of org.apache.rya.api.utils.NullableStatementImpl in project incubator-rya by apache.

the class HasValueVisitor method meetSP.

/**
 * 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();
    // Both require defined predicate
    if (predVar != null && predVar.getValue() != null) {
        final URI predURI = (URI) predVar.getValue();
        if (RDF.TYPE.equals(predURI) && 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<URI, Set<Value>> sufficientValues = inferenceEngine.getHasValueByType(objType);
            if (sufficientValues.size() > 0) {
                final Var valueVar = new Var("v-" + UUID.randomUUID());
                TupleExpr currentNode = node.clone();
                for (URI 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(predURI);
            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));
            }
        }
    }
}

Example 12 with NullableStatementImpl

use of org.apache.rya.api.utils.NullableStatementImpl in project incubator-rya by apache.

the class ParallelEvaluationStrategyImpl method evaluate.

public CloseableIteration<BindingSet, QueryEvaluationException> evaluate(final StatementPattern sp, Collection<BindingSet> bindings) throws QueryEvaluationException {
    final Var subjVar = sp.getSubjectVar();
    final Var predVar = sp.getPredicateVar();
    final Var objVar = sp.getObjectVar();
    final Var cntxtVar = sp.getContextVar();
    List<Map.Entry<Statement, BindingSet>> stmts = new ArrayList<Map.Entry<Statement, BindingSet>>();
    Iteration<? extends Map.Entry<Statement, BindingSet>, QueryEvaluationException> iter;
    if (sp instanceof FixedStatementPattern) {
        Collection<Map.Entry<Statement, BindingSet>> coll = Lists.newArrayList();
        for (BindingSet binding : bindings) {
            Value subjValue = getVarValue(subjVar, binding);
            Value predValue = getVarValue(predVar, binding);
            Value objValue = getVarValue(objVar, binding);
            Resource contxtValue = (Resource) getVarValue(cntxtVar, binding);
            for (Statement st : ((FixedStatementPattern) sp).statements) {
                if (!((subjValue != null && !subjValue.equals(st.getSubject())) || (predValue != null && !predValue.equals(st.getPredicate())) || (objValue != null && !objValue.equals(st.getObject())))) {
                    coll.add(new RdfCloudTripleStoreUtils.CustomEntry<Statement, BindingSet>(st, binding));
                }
            }
        }
        iter = new IteratorIteration(coll.iterator());
    } else if (sp instanceof TransitivePropertySP && ((subjVar != null && subjVar.getValue() != null) || (objVar != null && objVar.getValue() != null)) && sp.getPredicateVar() != null) {
        // if this is a transitive prop ref, we need to make sure that either the subj or obj is not null
        // TODO: Cannot handle a open ended transitive property where subj and obj are null
        // TODO: Should one day handle filling in the subj or obj with bindings and working this
        // TODO: a lot of assumptions, and might be a large set returned causing an OME
        Set<Statement> sts = null;
        try {
            sts = inferenceEngine.findTransitiveProperty((Resource) getVarValue(subjVar), (URI) getVarValue(predVar), getVarValue(objVar), (Resource) getVarValue(cntxtVar));
        } catch (InferenceEngineException e) {
            throw new QueryEvaluationException(e);
        }
        Collection<Map.Entry<Statement, BindingSet>> coll = new ArrayList();
        for (BindingSet binding : bindings) {
            for (Statement st : sts) {
                coll.add(new RdfCloudTripleStoreUtils.CustomEntry<Statement, BindingSet>(st, binding));
            }
        }
        iter = new IteratorIteration(coll.iterator());
    } else {
        for (BindingSet binding : bindings) {
            Value subjValue = getVarValue(subjVar, binding);
            Value predValue = getVarValue(predVar, binding);
            Value objValue = getVarValue(objVar, binding);
            Resource contxtValue = (Resource) getVarValue(cntxtVar, binding);
            if ((subjValue != null && !(subjValue instanceof Resource)) || (predValue != null && !(predValue instanceof URI))) {
                continue;
            }
            stmts.add(new RdfCloudTripleStoreUtils.CustomEntry<Statement, BindingSet>(new NullableStatementImpl((Resource) subjValue, (URI) predValue, objValue, contxtValue), binding));
        }
        if (stmts.size() == 0) {
            return new EmptyIteration();
        }
        iter = ((RdfCloudTripleStoreConnection.StoreTripleSource) tripleSource).getStatements(stmts);
    }
    return new ConvertingIteration<Map.Entry<Statement, BindingSet>, BindingSet, QueryEvaluationException>(iter) {

        @Override
        protected BindingSet convert(Map.Entry<Statement, BindingSet> stbs) throws QueryEvaluationException {
            Statement st = stbs.getKey();
            BindingSet bs = stbs.getValue();
            QueryBindingSet result = new QueryBindingSet(bs);
            // contain a Value for that Var name
            if (subjVar != null && !subjVar.isConstant() && !result.hasBinding(subjVar.getName())) {
                result.addBinding(subjVar.getName(), st.getSubject());
            }
            if (predVar != null && !predVar.isConstant() && !result.hasBinding(predVar.getName())) {
                result.addBinding(predVar.getName(), st.getPredicate());
            }
            if (objVar != null && !objVar.isConstant() && !result.hasBinding(objVar.getName())) {
                result.addBinding(objVar.getName(), st.getObject());
            }
            if (cntxtVar != null && !cntxtVar.isConstant() && !result.hasBinding(cntxtVar.getName()) && st.getContext() != null) {
                result.addBinding(cntxtVar.getName(), st.getContext());
            }
            return result;
        }
    };
}