package org.neo4j.kernel;
import java.util.Collections;
import java.util.Iterator;
import java.util.Map;
import org.neo4j.graphdb.Direction;
import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Relationship;
import org.neo4j.graphdb.RelationshipType;
import org.neo4j.helpers.collection.ArrayIterator;
import org.neo4j.helpers.collection.NestingIterator;
public final class OrderedByTypeExpander extends
StandardExpander.RegularExpander
{
public OrderedByTypeExpander()
{
this( new RelationshipType[0],
Collections.<String, Direction>emptyMap() );
}
OrderedByTypeExpander( RelationshipType[] types,
Map<String, Direction> directions )
{
super( types, directions );
}
@Override
RegularExpander createNew( RelationshipType[] newTypes,
Map<String, Direction> newDirections )
{
return new OrderedByTypeExpander( newTypes, newDirections );
}
@Override
Iterator<Relationship> doExpand( final Node start )
{
return new NestingIterator<Relationship, RelationshipType>(
new ArrayIterator<RelationshipType>( types ) )
{
@Override
protected Iterator<Relationship> createNestedIterator(
RelationshipType type )
{
Direction dir = directions.get( type.name() );
dir = ( dir == null ) ? Direction.BOTH : dir;
return ( ( dir == Direction.BOTH ) ? start.getRelationships( type )
: start.getRelationships( type, dir ) ).iterator();
}
};
}
}