public List<ChallengeHandler> lookup(String location){
  List<ChallengeHandler> result=Collections.emptyList();
  if (location != null) {
    Node<ChallengeHandler,UriElement> resultNode=findBestMatchingNode(location);
    if (resultNode != null) {
      return resultNode.getValues();
    }
  }
  return result;
}

public List < ChallengeHandler > lookup ( String location ) { List < ChallengeHandler > result = Collections . emptyList ( ) ; if ( location != null ) { Node < ChallengeHandler , UriElement > resultNode = findBestMatchingNode ( location ) ; if ( resultNode != null ) { return resultNode . getValues ( ) ; } } return result ; }
locate all challenge handlers to serve the given location .
