/**
* Copyright (c) 2002-2011 "Neo Technology,"
* Network Engine for Objects in Lund AB [http://neotechnology.com]
*
* This file is part of Neo4j.
*
* Neo4j is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.neo4j.graphdb.traversal;
import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Path;
import org.neo4j.graphdb.Relationship;
import org.neo4j.graphdb.RelationshipExpander;
/**
* Represents a {@link Path position} and a {@link RelationshipExpander} with a
* traversal context, for example parent and an iterator of relationships to go
* next. It's a base to write a {@link BranchSelector} on top of.
*/
public interface TraversalBranch
{
/**
* The parent expansion source which created this {@link TraversalBranch}.
* @return the parent of this expansion source.
*/
TraversalBranch parent();
/**
* The position represented by this expansion source.
* @return the position represented by this expansion source.
*/
Path position();
/**
* The depth for this expansion source compared to the start node of the
* traversal.
* @return the depth of this expansion source.
*/
int depth();
/**
* The node for this expansion source.
* @return the node for this expansion source.
*/
Node node();
/**
* The relationship for this expansion source. It's the relationship
* which was traversed to get to this expansion source.
* @return the relationship for this expansion source.
*/
Relationship relationship();
/**
* Returns the next expansion source from the expanded relationships
* from the current node.
*
* @return the next expansion source from this expansion source.
*/
TraversalBranch next();
/**
* Returns the number of relationships this expansion source has expanded.
* In this count isn't included the relationship which led to coming here
* (since that could also be traversed, although skipped, when expanding
* this source).
*
* @return the number of relationships this expansion source has expanded.
*/
int expanded();
Evaluation evaluation();
void initialize();
}