code: private boolean handleArtificialDominanceRelation(SDocumentGraph graph,
      SNode source, SNode target,
      SRelation rel, SLayer layer,
      long componentID, long pre)
    {
      List<SRelation<SNode,SNode>> mirrorRelations = graph.getRelations(source.getId(),
        target.getId());
      if (mirrorRelations != null && mirrorRelations.size() > 0)
      {
        for (Relation mirror : mirrorRelations)
  
        {
          if (mirror != rel && mirror instanceof SRelation)
          {
            // check layer
            SRelation mirrorRel = (SRelation) mirror;
  
            Set<SLayer> mirrorLayers = mirrorRel.getLayers();
            if (mirrorLayers != null)
            {
              for (SLayer mirrorLayer : mirrorLayers)
              {
                if (mirrorLayer == layer)
                {
                  // adjust the feature of the mirror relation to include
                  // information about the artificial dominance relation
                  RelannisEdgeFeature mirrorFeat = RelannisEdgeFeature.
                    extract(mirrorRel);
                  mirrorFeat.setArtificialDominanceComponent(componentID);
                  mirrorFeat.setArtificialDominancePre(pre);
                  mirrorRel.removeLabel(ANNIS_NS, FEAT_RELANNIS_EDGE);
                  mirrorRel.createFeature(ANNIS_NS, FEAT_RELANNIS_EDGE,
                    mirrorFeat);
  
                  return true;
                }
              }
            }
          }
        }
      }
  
      return false;
    }
docs: In ANNIS there is a special combined dominance component which has an empty
  name, but which should not directly be included in the Salt graph.
  
  This functions checks if a dominance relation with empty name has a
  "mirror" relation which is inside the same layer and between the same nodes
  but has an relation name. If yes the original dominance relation is an
  artificial one. The function will return true in this case and update the
  mirror relation to include information about the artificial dominance
  relation.
  
  @param graph
  @param rel
  @parem layer
  @param componentID
  @param pre
  @return True if the dominance relation was an artificial one