@Override
  public void setPosition(Integer startNode, Integer finalNode, AggregatePositioner source)
  {
    if (startNode != null)
      getStartNodeValueLabel().setText(startNode.toString());
    else
      getStartNodeValueLabel().setText("Not set");

    if (finalNode != null)
      getFinalNodeValueLabel().setText(finalNode.toString());
    else
      getFinalNodeValueLabel().setText("Not set");

    if (dataSource != null && startNode != null && finalNode != null)
    {
      IntegerAggregate aggregate = dataSource.getAggregate(startNode, finalNode);
      if (aggregate != null && !aggregate.isNonterminating())
        getHopCountValueLabel().setText(aggregate.getValue().toString());
      else if (aggregate != null && aggregate.isNonterminating())
        getHopCountValueLabel().setText("Non terminating");
      else
        getHopCountValueLabel().setText("Not set");
    }
  }