private Map<Literal, Collection<LabeledConcept>> orderResourcesByLabel() throws OpenRDFException {
    Map<Literal, Collection<LabeledConcept>> resourcesByLabel =
        new HashMap<Literal, Collection<LabeledConcept>>();

    for (LabeledConcept labeledResource : resourceLabelsCollector.getLabeledConcepts()) {
      Literal literal = labeledResource.getLiteral();

      Collection<LabeledConcept> resourcesForLiteral = resourcesByLabel.get(literal);
      if (resourcesForLiteral == null) {
        resourcesForLiteral = new HashSet<LabeledConcept>();
        resourcesByLabel.put(literal, resourcesForLiteral);
      }

      resourcesForLiteral.add(labeledResource);
    }

    return resourcesByLabel;
  }
 @Override
 public void setRepositoryConnection(RepositoryConnection repCon) {
   resourceLabelsCollector.setRepositoryConnection(repCon);
   super.setRepositoryConnection(repCon);
 }