/*
* Copyright (c) 2002-2009 "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.kernel.impl.core;
import java.util.HashSet;
import java.util.NoSuchElementException;
import java.util.Set;
import org.neo4j.kernel.impl.util.IntArray;
class RelTypeElement extends RelTypeElementIterator
{
private final IntArray src;
private final IntArray add;
private final Set<Integer> remove = new HashSet<Integer>();
private boolean srcTraversed = false;
private boolean addTraversed = false;
private int position = 0;
private Integer nextElement = null;
static RelTypeElementIterator create( String type, NodeImpl node,
IntArray src, IntArray add, IntArray remove )
{
if ( add == null && remove == null )
{
return new FastRelTypeElement( type, node, src );
}
return new RelTypeElement( type, node, src, add, remove );
}
private RelTypeElement( String type, NodeImpl node, IntArray src,
IntArray add, IntArray remove )
{
super( type, node );
this.src = src;
if ( src == null )
{
srcTraversed = true;
}
if ( add == null )
{
addTraversed = true;
}
this.add = add;
if ( remove != null )
{
for ( int i = 0; i < remove.length(); i++ )
{
this.remove.add( remove.get( i ) );
}
}
}
public boolean hasNext()
{
if ( nextElement != null )
{
return true;
}
while ( !addTraversed && position < add.length() )
{
int value = add.get( position++ );
if ( position >= add.length() )
{
addTraversed = true;
position = 0;
}
if ( !remove.contains( value ) )
{
nextElement = value;
return true;
}
}
while ( !srcTraversed )
{
if ( position >= src.length() )
{
while ( getNode().getMoreRelationships() &&
position >= src.length() );
if ( position >= src.length() )
{
srcTraversed = true;
position = 0;
return false;
}
}
int value = src.get( position++ );
if ( !remove.contains( value ) )
{
nextElement = value;
return true;
}
}
return false;
}
public Integer next()
{
hasNext();
if ( nextElement != null )
{
Integer elementToReturn = nextElement;
nextElement = null;
return elementToReturn;
}
throw new NoSuchElementException();
}
public void remove()
{
throw new UnsupportedOperationException();
}
}