/**
* Copyright (c) 2002-2010 "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;
public interface UniquenessFilter
{
/**
* The check whether or not to expand the first branch is a separate
* method because it may contain checks which would be unnecessary for
* all other checks. So it's purely an optimization.
*
* @param branch the first branch to check, i.e. the branch representing
* the start node in the traversal.
* @return whether or not {@code branch} is unique, and hence can be
* visited in this traversal.
*/
boolean checkFirst( TraversalBranch branch );
/**
* Checks whether or not {@code branch} is unique, and hence can be
* visited in this traversal.
* @param branch the {@link TraversalBranch} to check for uniqueness.
* @param remember whether or not to remember {@code branch}. If
* {@code remember} is {@code false} then no state in this filter must be
* changed.
* @return whether or not {@code branch} is unique, and hence can be
* visited in this traversal.
*/
boolean check( TraversalBranch branch, boolean remember );
}