code: private void adjust(ExtendedCisTrans elem) {
  
          IBond   middle = elem.getFocus();
          IAtom[] ends   = ExtendedCisTrans.findTerminalAtoms(container, middle);
          IBond[] bonds  = elem.getCarriers().toArray(new IBond[2]);
  
          IAtom left  = ends[0];
          IAtom right = ends[1];
  
          int p = parity(elem);
          int q = parity(getAtoms(left, bonds[0].getOther(left), right))
                  * parity(getAtoms(right, bonds[1].getOther(right), left));
  
          // configuration is unspecified? then we add an unspecified bond.
          // note: IDoubleBondStereochemistry doesn't indicate this yet
          if (p == 0) {
              for (IBond bond : container.getConnectedBondsList(left))
                  bond.setStereo(IBond.Stereo.NONE);
              for (IBond bond : container.getConnectedBondsList(right))
                  bond.setStereo(IBond.Stereo.NONE);
              bonds[0].setStereo(IBond.Stereo.UP_OR_DOWN);
              return;
          }
  
          // configuration is already correct
          if (p == q) return;
  
          Arrays.fill(visited, false);
          visited[atomToIndex.get(left)] = true;
  
          if (ringSearch.cyclic(atomToIndex.get(middle.getBegin()),
                                atomToIndex.get(middle.getEnd()))) {
              return;
          }
  
          for (int w : graph[atomToIndex.get(right)]) {
              if (!visited[w]) reflect(w, middle);
          }
      }
docs: Adjust the configuration of the cumulated double bonds to be
  either Cis or Trans.
  
  @param elem the stereo element to adjust