Examples of org.neo4j.graphdb.Relationship

org.neo4j.graphdb.Relationship
we have: (a) --- REL_TYPE ---> (b) assert rel. {@link Relationship#getStartNode() getStartNode}().equals( a ); assert rel. {@link Relationship#getEndNode() getEndNode}().equals( b ); assert rel. {@link Relationship#getNodes() getNodes}()[0].equals( a ) && rel. {@link Relationship#getNodes() getNodes}()[1].equals( b ); Even though all relationships have a direction they are equally well traversed in both directions so there's no need to create duplicate relationships in the opposite direction (with regard to traversal or performance).
Furthermore, Neo4j guarantees that a relationship is never "hanging freely," i.e. {@link #getStartNode()}, {@link #getEndNode()}, {@link #getOtherNode(Node)} and {@link #getNodes()} are guaranteed to alwaysreturn valid, non-null nodes.
The id of a relationship is unique, but may not be unique over time since neo4j reuses deleted ids. See http://wiki.neo4j.org/content/Id_Reuse

     *
     * @return the relationship that was created between the indexedNode and the end node..
     */
    public Relationship createRelationshipTo( Node node )
    {
        Relationship keyValueRelationship = nodeCollection.addNode( node );
        if ( !keyValueRelationship.hasProperty( RELATIONSHIP_DIRECTION ) )
        {
            keyValueRelationship.setProperty( RELATIONSHIP_DIRECTION, direction.name() );
        }
        if ( !keyValueRelationship.hasProperty( RELATIONSHIP_TYPE ) )
        {
            keyValueRelationship.setProperty( RELATIONSHIP_TYPE, relType.name() );
        }
        return getRelationship( keyValueRelationship );
    }

View Full Code Here

        return new RelationshipIterator();
    }


    private NodeCollection getNodeCollection()
    {
        Relationship indexRelationship = null;
        for ( Relationship candidateRelationship : this.indexedNode.getRelationships( RelationshipTypes.NODE_COLLECTION, Direction.OUTGOING ) )
        {
            String relName = (String) candidateRelationship.getProperty( RELATIONSHIP_TYPE, null );
            if ( relType.name().equals( relName ) )
            {
                String dir = (String) candidateRelationship.getProperty( RELATIONSHIP_DIRECTION, null );
                if ( direction.name().equals( dir ) )
                {
                    if ( indexRelationship != null ) {
                        throw new IllegalStateException(
                            "Multiple IndexedRelationship's on the given node with relationship type: "  +
                                relType.name() + " and direction: " + direction.name());
                    }
                    
                    indexRelationship = candidateRelationship;
                }
            }
        }


        if ( indexRelationship != null )
        {
            return NodeCollectionLoader.load(indexRelationship.getEndNode());
        }


        return null;
    }

View Full Code Here

            public Neo4jEdge next() {
                if (!checkTransaction) {
                    return new Neo4jEdge(this.itty.next(), graph);
                } else {
                    if (null != this.nextRelationship) {
                        final Relationship temp = this.nextRelationship;
                        this.nextRelationship = null;
                        return new Neo4jEdge(temp, graph);
                    } else {
                        while (true) {
                            final Relationship relationship = this.itty.next();
                            try {
                                relationship.hasProperty(DUMMY_PROPERTY);
                                return new Neo4jEdge(relationship, graph);
                            } catch (final IllegalStateException e) {
                                // tried to access a relationship not available to the transaction
                            }
                        }
                    }
                }
            }


            public boolean hasNext() {
                if (!checkTransaction)
                    return this.itty.hasNext();
                else {
                    if (null != this.nextRelationship)
                        return true;
                    else {
                        while (this.itty.hasNext()) {
                            final Relationship relationship = this.itty.next();
                            try {
                                relationship.hasProperty(DUMMY_PROPERTY);
                                this.nextRelationship = relationship;
                                return true;
                            } catch (final IllegalStateException e) {
                            }
                        }

View Full Code Here

                graph.autoStartTransaction(false);
                if (!checkTransaction) {
                    return new Neo4j2Edge(this.itty.next(), graph);
                } else {
                    if (null != this.nextRelationship) {
                        final Relationship temp = this.nextRelationship;
                        this.nextRelationship = null;
                        return new Neo4j2Edge(temp, graph);
                    } else {
                        while (true) {
                            final Relationship relationship = this.itty.next();
                            try {
                                if (!graph.relationshipIsDeleted(relationship.getId())) {
                                    return new Neo4j2Edge(relationship, graph);
                                }
                            } catch (final IllegalStateException e) {
                                // tried to access a relationship not available to the transaction
                            }
                        }
                    }
                }
            }


            public boolean hasNext() {
                graph.autoStartTransaction(false);
                if (!checkTransaction)
                    return this.itty.hasNext();
                else {
                    if (null != this.nextRelationship)
                        return true;
                    else {
                        while (this.itty.hasNext()) {
                            final Relationship relationship = this.itty.next();
                            try {
                                if (!graph.relationshipIsDeleted(relationship.getId())) {
                                    this.nextRelationship = relationship;
                                    return true;
                                }
                            } catch (final IllegalStateException e) {
                            }

View Full Code Here

            if( rel.getEndNode().equals( entityNode ) )
            {
                return false;
            }
        }
        Relationship rel = underlyingNode.createRelationshipTo( entityNode,
                                                                RelTypes.MANY_ASSOCIATION );
        setRelationshipIndex( rel, index );
        incrementCount();
        entity.setUpdated();
        return true;

View Full Code Here


    @Override
    public NamedAssociationState namedAssociationValueOf( QualifiedName stateName )
    {
        RelationshipType namedAssociation = namedAssociation( stateName );
        Relationship rel = underlyingNode.getSingleRelationship( namedAssociation, Direction.OUTGOING );
        if( rel != null )
        {
            return new NeoNamedAssociationState( uow, this, rel.getEndNode() );
        }
        Node node = uow.getNeo().createNode();
        node.setProperty( NeoNamedAssociationState.COUNT, 0 );
        underlyingNode.createRelationshipTo( node, namedAssociation );
        return new NeoNamedAssociationState( uow, this, node );

View Full Code Here

    
    @Override
    public ManyAssociationState manyAssociationValueOf( QualifiedName stateName )
    {
        RelationshipType manyAssociation = manyAssociation( stateName );
        Relationship rel = underlyingNode.getSingleRelationship( manyAssociation, Direction.OUTGOING );
        if( rel != null )
        {
            return new NeoManyAssociationState( uow, this, rel.getEndNode() );
        }
        Node node = uow.getNeo().createNode();
        node.setProperty( NeoManyAssociationState.COUNT, 0 );
        underlyingNode.createRelationshipTo( node, manyAssociation );
        return new NeoManyAssociationState( uow, this, node );

View Full Code Here

    }


    @Override
    public EntityReference associationValueOf( QualifiedName stateName )
    {
        Relationship rel = underlyingNode.getSingleRelationship( association( stateName ), Direction.OUTGOING );
        if( rel != null )
        {
            String entityId = (String) rel.getEndNode().getProperty( ENTITY_ID );
            return new EntityReference( entityId );
        }
        return null;
    }

View Full Code Here


    @Override
    public void setAssociationValue( QualifiedName stateName, EntityReference newEntity )
    {
        RelationshipType association = association( stateName );
        Relationship rel = underlyingNode.getSingleRelationship( association, Direction.OUTGOING );
        if( rel != null )
        {
            Node otherNode = rel.getEndNode();
            if( otherNode.getProperty( ENTITY_ID ).equals( identity().identity() ) )
            {
                otherNode.delete();
            }
            rel.delete();
        }
        if( newEntity != null )
        {
            Node otherNode = uow.getEntityStateNode( newEntity );
            if( otherNode.equals( underlyingNode ) )

View Full Code Here

                rel.delete();
                decrementCount();
                break;
            }
        }
        Relationship rel = underlyingNode.createRelationshipTo( entityNode, RelTypes.NAMED_ASSOCIATION );
        setRelationshipName( rel, name );
        incrementCount();
        entity.setUpdated();
        return true;
    }

View Full Code Here

0 1 2 3 4 5 6 7 8 9

TOP

Related Classes of org.neo4j.graphdb.Relationship

com.cedarsoft.serialization.neo4j.AbstractNeo4jSerializer

com.drighetto.neo4j.SocialNetworkSample

com.eugeneborshch.routecalculator.optimize.WayStartNodeFinder

com.graphaware.common.util.DirectionUtilsTest

de.alpengeist.NeoFeeder

de.metalcon.socialgraph.NeoUtils

er.neo4jadaptor.ersatz.neo4j.Neo4JNodeErsatz

examples.ImdbExampleTest

examples.PathFindingExamplesTest

ie.transportdublin.shortestpath.ShortestPath

All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.