Examples with Traverser org.neo4j.graphdb.traversal.Traverser used on opensource projects

Example 21 with Traverser

use of org.neo4j.graphdb.traversal.Traverser in project neo4j-mobile-android by neo4j-contrib.

the class Dijkstra method findAllPaths.

public Iterable<WeightedPath> findAllPaths(Node start, final Node end) {
    Predicate<Path> filter = new Predicate<Path>() {

        public boolean accept(Path position) {
            return position.endNode().equals(end);
        }
    };
    final Traverser traverser = TRAVERSAL.expand(expander).order(new SelectorFactory(costEvaluator)).filter(filter).traverse(start);
    return new Iterable<WeightedPath>() {

        public Iterator<WeightedPath> iterator() {
            return new StopAfterWeightIterator(traverser.iterator(), costEvaluator);
        }
    };
}

Example 22 with Traverser

use of org.neo4j.graphdb.traversal.Traverser in project graphdb by neo4j-attic.

the class TreeGraphTest method relationshipsIteratorReturnAllNodes.

@Test
public void relationshipsIteratorReturnAllNodes() throws Exception {
    Traverser traverser = Traversal.description().traverse(referenceNode());
    int count = 0;
    for (Relationship relationship : traverser.relationships()) {
        assertNotNull("returned relationships should not be. relationship #" + count, relationship);
        count++;
    }
    assertEquals(12, count);
}

Example 23 with Traverser

use of org.neo4j.graphdb.traversal.Traverser in project graphdb by neo4j-attic.

the class TreeGraphTest method testBreadthFirst.

@Test
public void testBreadthFirst() throws Exception {
    Traverser traverser = Traversal.description().breadthFirst().traverse(referenceNode());
    Stack<Set<String>> levels = new Stack<Set<String>>();
    levels.push(new HashSet<String>(Arrays.asList("5", "6", "7", "8", "9", "A", "B", "C", "D")));
    levels.push(new HashSet<String>(Arrays.asList("2", "3", "4")));
    levels.push(new HashSet<String>(Arrays.asList("1")));
    assertLevels(traverser, levels);
}

Example 24 with Traverser

use of org.neo4j.graphdb.traversal.Traverser in project graphdb by neo4j-attic.

the class TreeGraphTest method testPostorderDepthFirstReturnsDeeperNodesFirst.

@Test
public void testPostorderDepthFirstReturnsDeeperNodesFirst() {
    Traverser traverser = Traversal.description().order(Traversal.postorderDepthFirst()).traverse(referenceNode());
    int i = 0;
    List<String> encounteredNodes = new ArrayList<String>();
    for (Path pos : traverser) {
        encounteredNodes.add((String) pos.endNode().getProperty("name"));
        assertEquals(expectedDepth((12 - i++)), pos.length());
    }
    assertEquals(13, i);
    assertTrue(encounteredNodes.indexOf("5") < encounteredNodes.indexOf("2"));
    assertTrue(encounteredNodes.indexOf("6") < encounteredNodes.indexOf("2"));
    assertTrue(encounteredNodes.indexOf("7") < encounteredNodes.indexOf("2"));
    assertTrue(encounteredNodes.indexOf("8") < encounteredNodes.indexOf("3"));
    assertTrue(encounteredNodes.indexOf("9") < encounteredNodes.indexOf("3"));
    assertTrue(encounteredNodes.indexOf("A") < encounteredNodes.indexOf("3"));
    assertTrue(encounteredNodes.indexOf("B") < encounteredNodes.indexOf("4"));
    assertTrue(encounteredNodes.indexOf("C") < encounteredNodes.indexOf("4"));
    assertTrue(encounteredNodes.indexOf("D") < encounteredNodes.indexOf("4"));
    assertTrue(encounteredNodes.indexOf("2") < encounteredNodes.indexOf("1"));
    assertTrue(encounteredNodes.indexOf("3") < encounteredNodes.indexOf("1"));
    assertTrue(encounteredNodes.indexOf("4") < encounteredNodes.indexOf("1"));
}

Example 25 with Traverser

use of org.neo4j.graphdb.traversal.Traverser in project neo4j by neo4j.

the class GraphCloner method clonedSubgraph.

@PluginTarget(Node.class)
public Node clonedSubgraph(@Source Node startNode, @Parameter(name = "depth", optional = false) Integer depth) {
    GraphDatabaseService graphDb = startNode.getGraphDatabase();
    try (Transaction tx = graphDb.beginTx()) {
        Traverser traverse = traverseToDepth(graphDb, startNode, depth);
        Iterator<Node> nodes = traverse.nodes().iterator();
        HashMap<Node, Node> clonedNodes = cloneNodes(graphDb, nodes);
        for (Node oldNode : clonedNodes.keySet()) {
            // give me the matching new node
            Node newStartNode = clonedNodes.get(oldNode);
            // Now let's go through the relationships and copy them over
            Iterator<Relationship> oldRelationships = oldNode.getRelationships(Direction.OUTGOING).iterator();
            while (oldRelationships.hasNext()) {
                Relationship oldRelationship = oldRelationships.next();
                Node newEndNode = clonedNodes.get(oldRelationship.getEndNode());
                if (newEndNode != null) {
                    Relationship newRelationship = newStartNode.createRelationshipTo(newEndNode, oldRelationship.getType());
                    cloneProperties(oldRelationship, newRelationship);
                }
            }
        }
        tx.success();
        return clonedNodes.get(startNode);
    }
}