}
};
final AccumulativeGridSampler<WTWD> gridSampler = new AccumulativeGridSampler<WTWD>(
sampleGrid, accMetric);
SPTWalker johnny = new SPTWalker(spt);
johnny.walk(new SPTVisitor() {
@Override
public final boolean accept(Edge e) {
return e instanceof StreetEdge;
}