public T[] bestPath(Class pathClass) {
    if (bestEntry == null) return null ;
    final Batch <T> pathTiles = new Batch <T> () ;
    for (Entry next = bestEntry ; next != null ; next = next.prior) {
      pathTiles.add(next.refers) ;
    }
    if (verbose) I.say("Path size: "+pathTiles.size()) ;
    int len = pathTiles.size() ;
    T path[] = (T[]) Array.newInstance(pathClass, len) ;
    for (T t : pathTiles) path[--len] = t ;
    return path ;
  }