code: public int getEnergies(IAtom sourceAtom, IAtom targetAtom, Order bondOrder) {
          int dKJPerMol = -1;
  
          for (Map.Entry<Integer, BondEnergy> entry : bondEngergies.entrySet()) {
              BondEnergy bondEnergy = entry.getValue();
              String atom1 = bondEnergy.getSymbolFirstAtom();
              String atom2 = bondEnergy.getSymbolSecondAtom();
              if ((atom1.equalsIgnoreCase(sourceAtom.getSymbol()) && atom2.equalsIgnoreCase(targetAtom.getSymbol()))
                      || (atom2.equalsIgnoreCase(sourceAtom.getSymbol()) && atom1
                              .equalsIgnoreCase(targetAtom.getSymbol()))) {
  
                  Order order = bondEnergy.getBondOrder();
                  if (order.compareTo(bondOrder) == 0) {
                      dKJPerMol = bondEnergy.getEnergy();
                  }
              }
          }
          return dKJPerMol;
      }
docs: Returns bond energy for a bond type, given atoms and bond type
  @param sourceAtom First bondEnergy
  @param targetAtom Second bondEnergy
  @param bondOrder (single, double etc)
  @return bond energy