Examples with StandardExpander org.neo4j.graphdb.impl.StandardExpander used on opensource projects

Example 1 with StandardExpander

use of org.neo4j.graphdb.impl.StandardExpander in project neo4j by neo4j.

the class TestShortestPath method withFilters.

@Test
void withFilters() {
    // 
    try (Transaction transaction = graphDb.beginTx()) {
        graph.makeEdgeChain(transaction, "a,b,c,d");
        graph.makeEdgeChain(transaction, "a,g,h,d");
        final Node a = graph.getNode(transaction, "a");
        final Node d = graph.getNode(transaction, "d");
        final Node b = graph.getNode(transaction, "b");
        b.setProperty("skip", true);
        var context = new BasicEvaluationContext(transaction, graphDb);
        final Predicate<Node> filter = item -> {
            final boolean skip = (Boolean) item.getProperty("skip", false);
            return !skip;
        };
        testShortestPathFinder(context, finder -> assertPaths(finder.findAllPaths(a, d), "a,g,h,d"), ((StandardExpander) allTypesAndDirections()).addNodeFilter(filter), 10);
        transaction.commit();
    }
}

Example 2 with StandardExpander

use of org.neo4j.graphdb.impl.StandardExpander in project neo4j by neo4j.

the class TestShortestPath method filtersTouchesAllIntermediateNodes.

@Test
void filtersTouchesAllIntermediateNodes() {
    // 
    try (Transaction transaction = graphDb.beginTx()) {
        graph.makeEdgeChain(transaction, "a,b,c,d");
        final Node a = graph.getNode(transaction, "a");
        final Node d = graph.getNode(transaction, "d");
        Collection<Node> touchedByFilter = new HashSet<>();
        final Predicate<Node> filter = item -> {
            touchedByFilter.add(item);
            return true;
        };
        final PathExpander expander = PathExpanderBuilder.empty().add(R1, OUTGOING).addNodeFilter(filter).build();
        // final PathExpander expander = ((StandardExpander) PathExpanders.forTypeAndDirection(R1, OUTGOING)).addNodeFilter( filter );
        var context = new BasicEvaluationContext(transaction, graphDb);
        Path path = Iterables.single(shortestPath(context, expander, 10).findAllPaths(a, d));
        assertEquals(3, path.length());
        List<Node> nodes = Iterables.asList(path.nodes());
        List<Node> intermediateNodes = nodes.subList(1, nodes.size() - 1);
        assertTrue(touchedByFilter.containsAll(intermediateNodes), "touchedByFilter: " + touchedByFilter);
        assertFalse(touchedByFilter.contains(a));
        assertFalse(touchedByFilter.contains(d));
        transaction.commit();
    }
}