Examples with GraphDatabaseService org.neo4j.graphdb.GraphDatabaseService used on opensource projects

Example 81 with GraphDatabaseService

use of org.neo4j.graphdb.GraphDatabaseService in project neo4j by neo4j.

the class AStarPerformanceIT method somePerformanceTesting.

@Test
public void somePerformanceTesting() throws Exception {
    // GIVEN
    int numberOfNodes = 200000;
    GeoDataGenerator generator = new GeoDataGenerator(numberOfNodes, 5d, 1000, 1000);
    generator.generate(directory);
    // WHEN
    long[][] points = new long[][] { new long[] { 9415, 158154 }, new long[] { 89237, 192863 }, new long[] { 68072, 150484 }, new long[] { 186309, 194495 }, new long[] { 152097, 99289 }, new long[] { 92150, 161182 }, new long[] { 188446, 115873 }, new long[] { 85033, 7772 }, new long[] { 291, 86707 }, new long[] { 188345, 158468 } };
    GraphDatabaseService db = new TestGraphDatabaseFactory().newEmbeddedDatabase(directory.getAbsoluteFile());
    PathFinder<WeightedPath> algo = aStar(allTypesAndDirections(), doubleCostEvaluator("weight", 0), GeoDataGenerator.estimateEvaluator());
    for (int i = 0; i < 10; i++) {
        System.out.println("----- " + i);
        for (long[] p : points) {
            try (Transaction tx = db.beginTx()) {
                Node start = db.getNodeById(p[0]);
                Node end = db.getNodeById(p[1]);
                long time = currentTimeMillis();
                WeightedPath path = algo.findSinglePath(start, end);
                time = currentTimeMillis() - time;
                System.out.println("time: " + time + ", len:" + path.length() + ", weight:" + path.weight());
                tx.success();
            }
        }
    }
    // THEN
    db.shutdown();
}

Example 82 with GraphDatabaseService

use of org.neo4j.graphdb.GraphDatabaseService in project neo4j by neo4j.

the class AllPaths method instantiateTraverser.

@Override
protected Traverser instantiateTraverser(Node start, Node end) {
    //        // Legacy single-directional traversal (for reference or something)
    //        return traversal().expand( expander ).depthFirst().uniqueness( uniqueness() )
    //                .evaluator( toDepth( maxDepth ) ).evaluator( Evaluators.includeWhereEndNodeIs( end ) )
    //                .traverse( start );
    // Bidirectional traversal
    GraphDatabaseService db = start.getGraphDatabase();
    TraversalDescription base = db.traversalDescription().depthFirst().uniqueness(uniqueness());
    return db.bidirectionalTraversalDescription().startSide(base.expand(expander).evaluator(toDepth(maxDepth / 2))).endSide(base.expand(expander.reverse()).evaluator(toDepth(maxDepth - maxDepth / 2))).traverse(start, end);
}

Example 83 with GraphDatabaseService

use of org.neo4j.graphdb.GraphDatabaseService in project neo4j by neo4j.

the class DijkstraBidirectional method traverser.

private Traverser traverser(Node start, final Node end, PathInterest interest) {
    final MutableDouble shortestSoFar = new MutableDouble(Double.MAX_VALUE);
    final MutableDouble startSideShortest = new MutableDouble(0);
    final MutableDouble endSideShortest = new MutableDouble(0);
    PathExpander dijkstraExpander = new DijkstraBidirectionalPathExpander(expander, shortestSoFar, true, startSideShortest, endSideShortest, epsilon);
    GraphDatabaseService db = start.getGraphDatabase();
    TraversalDescription side = db.traversalDescription().expand(dijkstraExpander, stateFactory).order(new DijkstraSelectorFactory(interest, costEvaluator)).evaluator(new DijkstraBidirectionalEvaluator(costEvaluator)).uniqueness(Uniqueness.NODE_PATH);
    TraversalDescription startSide = side;
    TraversalDescription endSide = side.reverse();
    BidirectionalTraversalDescription traversal = db.bidirectionalTraversalDescription().startSide(startSide).endSide(endSide).collisionEvaluator(Evaluators.all()).collisionPolicy(new BranchCollisionPolicy() {

        @Override
        public BranchCollisionDetector create(Evaluator evaluator, Predicate<Path> pathPredicate) {
            return new DijkstraBranchCollisionDetector(evaluator, costEvaluator, shortestSoFar, epsilon, pathPredicate);
        }
    });
    lastTraverser = traversal.traverse(start, end);
    return lastTraverser;
}

Example 84 with GraphDatabaseService

use of org.neo4j.graphdb.GraphDatabaseService in project neo4j by neo4j.

the class ExactDepthPathFinder method instantiateTraverser.

@Override
protected Traverser instantiateTraverser(Node start, Node end) {
    GraphDatabaseService db = start.getGraphDatabase();
    TraversalDescription side = db.traversalDescription().breadthFirst().uniqueness(uniqueness).order(new BranchOrderingPolicy() {

        @Override
        public BranchSelector create(TraversalBranch startSource, PathExpander expander) {
            return new LiteDepthFirstSelector(startSource, startThreshold, expander);
        }
    });
    return db.bidirectionalTraversalDescription().startSide(side.expand(expander).evaluator(toDepth(onDepth / 2))).endSide(side.expand(expander.reverse()).evaluator(toDepth(onDepth - onDepth / 2))).collisionEvaluator(atDepth(onDepth)).traverse(start, end);
}

Example 85 with GraphDatabaseService

use of org.neo4j.graphdb.GraphDatabaseService in project neo4j by neo4j.

the class KernelRecoveryTest method shouldHandleWritesProperlyAfterRecovery.

@Test
public void shouldHandleWritesProperlyAfterRecovery() throws Exception {
    // Given
    EphemeralFileSystemAbstraction fs = fsRule.get();
    GraphDatabaseService db = newDB(fs);
    long node1 = createNode(db);
    // And given the power goes out
    EphemeralFileSystemAbstraction crashedFs = fs.snapshot();
    db.shutdown();
    try {
        db = newDB(crashedFs);
        long node2 = createNode(db);
        db.shutdown();
        // Then the logical log should be in sync
        File logFile = new File(storeDir, PhysicalLogFile.DEFAULT_NAME + PhysicalLogFile.DEFAULT_VERSION_SUFFIX + "0");
        assertThat(logEntries(crashedFs, logFile), containsExactly(// Tx before recovery
        startEntry(-1, -1), commandEntry(node1, NodeCommand.class), commandEntry(ReadOperations.ANY_LABEL, NodeCountsCommand.class), commitEntry(2), // Tx after recovery
        startEntry(-1, -1), commandEntry(node2, NodeCommand.class), commandEntry(ReadOperations.ANY_LABEL, NodeCountsCommand.class), commitEntry(3), // checkpoint
        checkPoint(new LogPosition(0, 250))));
    } finally {
        crashedFs.close();
    }
}