code: @Override
      public double getBondOrderSum(IAtom atom) {
          double count = 0;
          for (int i = 0; i < bondCount; i++) {
              if (bonds[i].contains(atom)) {
                  IBond.Order order = bonds[i].getOrder();
                  if (order != null) {
                      count += order.numeric();
                  }
              }
          }
          return count;
      }
docs: {@inheritDoc}