Java Extension类代码示例

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Test
public void testUnsupportedExtension() throws Exception {
    StatementPattern sp = new StatementPattern(new Var("x"), constant(TAKES), new Var("c"));
    List<ExtensionElem> elements = Arrays.asList(new ExtensionElem(new Var("x"), "renamed"),
            new ExtensionElem(new Not(new ValueConstant(VF.createLiteral(true))), "notTrue"),
            new ExtensionElem(new ValueConstant(TAKES), "constant"));
    Extension extensionNode = new Extension(sp, elements);
    QueryRoot queryTree = new QueryRoot(extensionNode);
    SparqlToPipelineTransformVisitor visitor = new SparqlToPipelineTransformVisitor(collection);
    queryTree.visit(visitor);
    Assert.assertTrue(queryTree.getArg() instanceof Extension);
    Assert.assertEquals(elements, ((Extension) queryTree.getArg()).getElements());
    TupleExpr innerQuery = ((Extension) queryTree.getArg()).getArg();
    Assert.assertTrue(innerQuery instanceof AggregationPipelineQueryNode);
    AggregationPipelineQueryNode pipelineNode = (AggregationPipelineQueryNode) innerQuery;
    Assert.assertEquals(Sets.newHashSet("x", "c"), pipelineNode.getAssuredBindingNames());
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
/**
 * Make a {@link MultiProjectionEvaluator} that processes the logic of a {@link MultiProjection}.
 *
 * @param multiProjection - Defines the projections that will be processed. (not null)
 * @param bNodeIdFactory - Creates the IDs for Blank Nodes. (not null)
 * @return A {@link MultiProjectionEvaluator} for the provided {@link MultiProjection}.
 */
public static MultiProjectionEvaluator make(final MultiProjection multiProjection, final BNodeIdFactory bNodeIdFactory) {
    requireNonNull(multiProjection);

    // Figure out if there are extensions.
    final TupleExpr arg = multiProjection.getArg();
    final Optional<Extension> extension = (arg instanceof Extension) ? Optional.of((Extension)arg): Optional.empty();

    // If there are, iterate through them and find any blank node source names.
    final Set<String> blankNodeSourceNames = new HashSet<>();
    if(extension.isPresent()) {
        for(final ExtensionElem elem : extension.get().getElements()) {
            if(elem.getExpr() instanceof BNodeGenerator) {
                blankNodeSourceNames.add( elem.getName() );
            }
        }
    }

    // Create a ProjectionEvaluator for each projection that is part of the multi.
    final Set<ProjectionEvaluator> projections = new HashSet<>();
    for(final ProjectionElemList projectionElemList : multiProjection.getProjections()) {
        projections.add( new ProjectionEvaluator(projectionElemList, extension) );
    }

    return new MultiProjectionEvaluator(projections, blankNodeSourceNames, bNodeIdFactory);
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Override
public void meet(Extension node) {
    Set<String> argBindings = node.getArg().getBindingNames();
    if (typeRequirement != null) {
        node.getElements().removeIf(elem -> {
            if (varName.equals(elem.getName())) {
                ValueExpr expr = elem.getExpr();
                if (expr == null) {
                    return true;
                }
                else if (expr instanceof Var) {
                    String fromName = ((Var) expr).getName();
                    if (getVarValue((Var) expr) == null && !argBindings.contains(fromName)) {
                        return true;
                    }
                }
            }
            return false;
        });
        meetUnaryTupleOperator(node);
    }
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Test
public void testConcreteSP() {
    Extension extension = new Extension(new SingletonSet(),
            new ExtensionElem(new ValueConstant(FOAF.PERSON), "x"),
            new ExtensionElem(new ValueConstant(RDF.TYPE), "y"),
            new ExtensionElem(new ValueConstant(OWL.CLASS), "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(FOAF.PERSON), p(RDF.TYPE), o(OWL.CLASS)));
    Assert.assertEquals(expected, visitor.getConsequents());
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Override
public void meet(final Projection node) throws TopologyBuilderException {
    final String id = PROJECTION_PREFIX + UUID.randomUUID();
    final Optional<Side> side = getSide(node);

    // If the arg is an Extension, there are rebindings that need to be
    // ignored since they do not have a processor node.
    TupleExpr downstreamNode = node.getArg();
    if (downstreamNode instanceof Extension) {
        downstreamNode = ((Extension) downstreamNode).getArg();
    }

    final ProjectionProcessorSupplier supplier = new ProjectionProcessorSupplier(
            ProjectionEvaluator.make(node),
            result -> getResult(side, result));

    entries.add(new ProcessorEntry(node, id, side, supplier, Lists.newArrayList(downstreamNode)));
    idMap.put(node, id);
    super.meet(node);
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Override
public void meet(final Extension n) {
    emit(n.getArg());
    if (!(n.getArg() instanceof SingletonSet)) {
        newline();
    }
    boolean first = true;
    for (final ExtensionElem e : n.getElements()) {
        final ValueExpr expr = e.getExpr();
        if (!(expr instanceof Var) || !((Var) expr).getName().equals(e.getName())) {
            if (!first) {
                newline();
            }
            emit("BIND (").emit(expr).emit(" AS ?").emit(e.getName()).emit(")");
            first = false;
        }
    }
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
private static Map<String, ExtensionElem> extractExtensions(final TupleExpr rootNode) {
    final Map<String, ExtensionElem> map = Maps.newHashMap();
    for (final UnaryTupleOperator node : extractQueryNodes(rootNode, true)) {
        if (node instanceof Extension) {
            for (final ExtensionElem elem : ((Extension) node).getElements()) {
                final String variable = elem.getName();
                final ValueExpr expression = elem.getExpr();
                if (!(expression instanceof Var)
                        || !((Var) expression).getName().equals(variable)) {
                    map.put(variable, elem);
                }
            }
        }
    }
    return map;
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Test
public void testPropertyPattern_constantSubj() throws Exception {
    final InferenceEngine inferenceEngine = mock(InferenceEngine.class);
    final Set<Resource> loveTypes = new HashSet<>();
    loveTypes.add(narcissist);
    when(inferenceEngine.getHasSelfImplyingProperty(love)).thenReturn(loveTypes);
    final Var subj = new Var("s", self);
    subj.setConstant(true);
    final Var obj = new Var("o");
    final Var pred = new Var("p", love);
    pred.setConstant(true);

    final Projection query = new Projection(new StatementPattern(subj, pred, obj),
            new ProjectionElemList(new ProjectionElem("s", "subject")));
    query.visit(new HasSelfVisitor(conf, inferenceEngine));

    Assert.assertTrue(query.getArg() instanceof Union);
    final Union union = (Union) query.getArg();
    Assert.assertTrue(union.getRightArg() instanceof StatementPattern);
    Assert.assertTrue(union.getLeftArg() instanceof Extension);
    final StatementPattern expectedRight = new StatementPattern(subj, pred, obj);
    final Extension expectedLeft = new Extension(
            new StatementPattern(subj, new Var(RDF.TYPE.stringValue(), RDF.TYPE), new Var("urn:Narcissist", narcissist)),
            new ExtensionElem(subj, "o"));
    Assert.assertEquals(expectedLeft, union.getLeftArg());
    Assert.assertEquals(expectedRight, union.getRightArg());
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Test
public void testPropertyPattern_constantObj() throws Exception {
    final InferenceEngine inferenceEngine = mock(InferenceEngine.class);
    final Set<Resource> loveTypes = new HashSet<>();
    loveTypes.add(narcissist);
    when(inferenceEngine.getHasSelfImplyingProperty(love)).thenReturn(loveTypes);
    final Var subj = new Var("s");
    final Var obj = new Var("o", self);
    obj.setConstant(true);
    final Var pred = new Var("p", love);
    pred.setConstant(true);

    final Projection query = new Projection(new StatementPattern(subj, pred, obj),
            new ProjectionElemList(new ProjectionElem("s", "subject")));
    query.visit(new HasSelfVisitor(conf, inferenceEngine));

    Assert.assertTrue(query.getArg() instanceof Union);
    final Union union = (Union) query.getArg();
    Assert.assertTrue(union.getRightArg() instanceof StatementPattern);
    Assert.assertTrue(union.getLeftArg() instanceof Extension);
    final StatementPattern expectedRight = new StatementPattern(subj, pred, obj);
    final Extension expectedLeft = new Extension(
            new StatementPattern(obj, new Var(RDF.TYPE.stringValue(), RDF.TYPE), new Var("urn:Narcissist", narcissist)),
            new ExtensionElem(obj, "s"));
    Assert.assertEquals(expectedLeft, union.getLeftArg());
    Assert.assertEquals(expectedRight, union.getRightArg());
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Override
public void meet(Extension extensionNode) throws Exception {
    extensionNode.visitChildren(this);
    if (extensionNode.getArg() instanceof AggregationPipelineQueryNode && extensionNode.getParentNode() != null) {
        AggregationPipelineQueryNode pipelineNode = (AggregationPipelineQueryNode) extensionNode.getArg();
        if (pipelineNode.extend(extensionNode.getElements())) {
            extensionNode.replaceWith(pipelineNode);
        }
    }
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Test
public void testExtension() throws Exception {
    QueryRoot queryTree = new QueryRoot(new Extension(
            new StatementPattern(new Var("x"), constant(TAKES), new Var("c")),
            new ExtensionElem(new Var("x"), "renamed"),
            new ExtensionElem(new ValueConstant(TAKES), "constant")));
    SparqlToPipelineTransformVisitor visitor = new SparqlToPipelineTransformVisitor(collection);
    queryTree.visit(visitor);
    Assert.assertTrue(queryTree.getArg() instanceof AggregationPipelineQueryNode);
    AggregationPipelineQueryNode pipelineNode = (AggregationPipelineQueryNode) queryTree.getArg();
    Assert.assertEquals(Sets.newHashSet("x", "c", "renamed", "constant"), pipelineNode.getAssuredBindingNames());
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
/**
 * Make a {@link ProjectionEvaluator} that processes the logic of a {@link Projection}.
 *
 * @param projection - Defines the projection that will be processed. (not null)
 * @return A {@link ProjectionEvaluator} for the provided {@link Projection}.
 */
public static ProjectionEvaluator make(final Projection projection) {
    requireNonNull(projection);

    final ProjectionElemList projectionElems = projection.getProjectionElemList();

    final TupleExpr arg = projection.getArg();
    final Optional<Extension> extension = arg instanceof Extension ? Optional.of((Extension)arg) : Optional.empty();

    return new ProjectionEvaluator(projectionElems, extension);
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
private String makeId(final QueryModelNode node) {
    checkNotNull(node);

    // Create the prefix of the id. This makes it a little bit more human readable.
    String prefix;
    if (node instanceof StatementPattern) {
        prefix = SP_PREFIX;
    } else if (node instanceof Filter) {
        prefix = FILTER_PREFIX;
    } else if (node instanceof Join || node instanceof LeftJoin) {
        prefix = JOIN_PREFIX;
    } else if (node instanceof Projection) {
        prefix = PROJECTION_PREFIX;
    } else if(node instanceof Extension) {
        prefix = AGGREGATION_PREFIX;
    }  else if (node instanceof Reduced) {
        prefix = CONSTRUCT_PREFIX;
    } else if(node instanceof PeriodicQueryNode) {
        prefix = PERIODIC_QUERY_PREFIX;
    } else {
        throw new IllegalArgumentException("Node must be of type {StatementPattern, Join, Filter, Extension, Projection} but was " + node.getClass());
    }

    final String unique = UUID.randomUUID().toString().replaceAll("-", "");
    // Put them together to create the Node ID.
    return prefix + "_" + unique;
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@Override
public void meet(Projection projection) {
    if (projection.getArg() instanceof Extension) {
        recordConsequent(projection.getProjectionElemList(),
                ((Extension) projection.getArg()).getElements());
    }
    else {
        recordConsequent(projection.getProjectionElemList(), Arrays.asList());
    }
}
 

import org.openrdf.query.algebra.Extension; //导入依赖的package包/类
@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());
}