package org.neo4j.kernel;
import org.neo4j.graphdb.traversal.TraversalBranch;
import org.neo4j.kernel.impl.cache.LruCache;
class RecentlyUnique extends AbstractUniquenessFilter
{
private static final Object PLACE_HOLDER = new Object();
private static final int DEFAULT_RECENT_SIZE = 10000;
private final LruCache<Long, Object> recentlyVisited;
RecentlyUnique( PrimitiveTypeFetcher type, Object parameter )
{
super( type );
parameter = parameter != null ? parameter : DEFAULT_RECENT_SIZE;
recentlyVisited = new LruCache<Long, Object>( "Recently visited",
((Number) parameter).intValue(), null );
}
public boolean check( TraversalBranch branch, boolean remember )
{
long id = type.getId( branch );
boolean add = recentlyVisited.get( id ) == null;
if ( add&remember )
{
recentlyVisited.put( id, PLACE_HOLDER );
}
return add;
}
}