package org.neo4j.graphalgo.impl.util;
import java.util.Iterator;
import org.neo4j.graphalgo.CostEvaluator;
import org.neo4j.graphalgo.WeightedPath;
import org.neo4j.graphdb.Path;
import org.neo4j.helpers.collection.PrefetchingIterator;
public class StopAfterWeightIterator extends PrefetchingIterator<WeightedPath>
{
private final Iterator<Path> paths;
private final CostEvaluator<Double> costEvaluator;
private Double foundWeight;
public StopAfterWeightIterator( Iterator<Path> paths,
CostEvaluator<Double> costEvaluator )
{
this.paths = paths;
this.costEvaluator = costEvaluator;
}
@Override
protected WeightedPath fetchNextOrNull()
{
if ( !paths.hasNext() )
{
return null;
}
WeightedPath path = new WeightedPathImpl( costEvaluator, paths.next() );
System.out.println( "found path " + path );
if ( foundWeight != null && path.weight() > foundWeight )
{
return null;
}
foundWeight = path.weight();
return path;
}
}