Examples with ExtensionElem org.openrdf.query.algebra.ExtensionElem used on opensource projects

Example 11 with ExtensionElem

use of org.openrdf.query.algebra.ExtensionElem in project incubator-rya by apache.

the class ConstructConsequentVisitorTest method testBNode.

@Test
public void testBNode() {
    Extension extension = new Extension(new SingletonSet(), new ExtensionElem(new Var("x"), "x"), new ExtensionElem(new BNodeGenerator(), "z"));
    Projection projection = new Projection(extension, new ProjectionElemList(new ProjectionElem("x", "subject"), new ProjectionElem("y", "predicate"), new ProjectionElem("z", "object")));
    ConstructConsequentVisitor visitor = new ConstructConsequentVisitor();
    projection.visit(visitor);
    Set<StatementPattern> expected = Sets.newHashSet(new StatementPattern(s(null), p(null), anon(o(null))));
    Assert.assertEquals(expected, visitor.getConsequents());
}

Example 12 with ExtensionElem

use of org.openrdf.query.algebra.ExtensionElem in project incubator-rya by apache.

the class ConstructConsequentVisitorTest method testGenericSP.

@Test
public void testGenericSP() {
    Extension extension = new Extension(new SingletonSet(), new ExtensionElem(new Var("z"), "z"));
    Projection projection = new Projection(extension, new ProjectionElemList(new ProjectionElem("x", "subject"), new ProjectionElem("y", "predicate"), new ProjectionElem("z", "object")));
    ConstructConsequentVisitor visitor = new ConstructConsequentVisitor();
    projection.visit(visitor);
    Set<StatementPattern> expected = Sets.newHashSet(new StatementPattern(s(null), p(null), o(null)));
    Assert.assertEquals(expected, visitor.getConsequents());
}

Example 13 with ExtensionElem

use of org.openrdf.query.algebra.ExtensionElem in project incubator-rya by apache.

the class ConstructConsequentVisitorTest method testMultiProjection.

@Test
public void testMultiProjection() {
    Extension extension = new Extension(new SingletonSet(), new ExtensionElem(new ValueConstant(RDF.TYPE), "rdftype"), new ExtensionElem(new ValueConstant(OWL.OBJECTPROPERTY), "owlprop"), new ExtensionElem(new ValueConstant(OWL.EQUIVALENTCLASS), "owleqcls"), new ExtensionElem(new ValueConstant(OWL.CLASS), "owlclass"));
    MultiProjection projection = new MultiProjection(extension, Arrays.asList(new ProjectionElemList(new ProjectionElem("cls", "subject"), new ProjectionElem("rdftype", "predicate"), new ProjectionElem("owlclass", "object")), new ProjectionElemList(new ProjectionElem("prop", "subject"), new ProjectionElem("rdftype", "predicate"), new ProjectionElem("owlprop", "object")), new ProjectionElemList(new ProjectionElem("owleqcls", "predicate"), new ProjectionElem("cls", "object"))));
    ConstructConsequentVisitor visitor = new ConstructConsequentVisitor();
    projection.visit(visitor);
    Set<StatementPattern> expected = Sets.newHashSet(new StatementPattern(s(null), p(RDF.TYPE), o(OWL.CLASS)), new StatementPattern(s(null), p(RDF.TYPE), o(OWL.OBJECTPROPERTY)), new StatementPattern(s(null), p(OWL.EQUIVALENTCLASS), o(null)));
    Assert.assertEquals(expected, visitor.getConsequents());
}

Example 14 with ExtensionElem

use of org.openrdf.query.algebra.ExtensionElem in project incubator-rya by apache.

the class AggregationPipelineQueryNode method extend.

/**
 * Add a SPARQL extension to the pipeline, if possible. An extension adds
 * some number of variables to the result. Adds a "$project" step to the
 * pipeline, but differs from the SPARQL project operation in that
 * 1) pre-existing variables are always kept, and 2) values of new variables
 * are defined by expressions, which may be more complex than simply
 * variable names. Not all expressions are supported. If unsupported
 * expression types are used in the extension, the pipeline will remain
 * unchanged and this method will return false.
 * @param extensionElements A list of new variables and their expressions
 * @return True if the extension was successfully converted into a pipeline
 *  step, false otherwise.
 */
public boolean extend(Iterable<ExtensionElem> extensionElements) {
    List<Bson> valueFields = new LinkedList<>();
    List<Bson> hashFields = new LinkedList<>();
    List<Bson> typeFields = new LinkedList<>();
    for (String varName : bindingNames) {
        valueFields.add(Projections.include(varName));
        hashFields.add(Projections.include(varName));
        typeFields.add(Projections.include(varName));
    }
    Set<String> newVarNames = new HashSet<>();
    for (ExtensionElem elem : extensionElements) {
        String name = elem.getName();
        if (!isValidFieldName(name)) {
            // If the field name is invalid, replace it internally
            name = replace(name);
        }
        // We can only handle certain kinds of value expressions; return
        // failure for any others.
        ValueExpr expr = elem.getExpr();
        final Object valueField;
        final Object hashField;
        final Object typeField;
        if (expr instanceof Var) {
            String varName = ((Var) expr).getName();
            valueField = "$" + varName;
            hashField = "$" + varName;
            typeField = "$" + varName;
        } else if (expr instanceof ValueConstant) {
            Value val = ((ValueConstant) expr).getValue();
            valueField = new Document("$literal", val.stringValue());
            hashField = new Document("$literal", SimpleMongoDBStorageStrategy.hash(val.stringValue()));
            if (val instanceof Literal) {
                typeField = new Document("$literal", ((Literal) val).getDatatype().stringValue());
            } else {
                typeField = null;
            }
        } else {
            // if not understood, return failure
            return false;
        }
        valueFields.add(Projections.computed(name, valueField));
        hashFields.add(Projections.computed(name, hashField));
        if (typeField != null) {
            typeFields.add(Projections.computed(name, typeField));
        }
        newVarNames.add(name);
    }
    assuredBindingNames.addAll(newVarNames);
    bindingNames.addAll(newVarNames);
    Bson projectOpts = Projections.fields(Projections.computed(VALUES, Projections.fields(valueFields)), Projections.computed(HASHES, Projections.fields(hashFields)), Projections.computed(TYPES, Projections.fields(typeFields)), Projections.include(LEVEL), Projections.include(TIMESTAMP));
    pipeline.add(Aggregates.project(projectOpts));
    return true;
}