/**
   * Get the resonance structures from an IMolecule.
   *
   * @param molecule The IMolecule to analyze
   * @return The different resonance structures
   */
  @TestMethod("testGetStructures_IMolecule")
  public IMoleculeSet getStructures(IMolecule molecule) {
    int countStructure = 0;
    IMoleculeSet setOfMol = molecule.getBuilder().newMoleculeSet();
    setOfMol.addMolecule(molecule);

    for (int i = 0; i < setOfMol.getMoleculeCount(); i++) {
      IMolecule mol = setOfMol.getMolecule(i);
      for (IReactionProcess aReactionsList : reactionsList) {
        IReactionProcess reaction = aReactionsList;
        IMoleculeSet setOfReactants = molecule.getBuilder().newMoleculeSet();
        setOfReactants.addMolecule(mol);
        try {
          IReactionSet setOfReactions = reaction.initiate(setOfReactants, null);
          if (setOfReactions.getReactionCount() != 0)
            for (int k = 0; k < setOfReactions.getReactionCount(); k++)
              for (int j = 0;
                  j < setOfReactions.getReaction(k).getProducts().getAtomContainerCount();
                  j++) {
                IMolecule product = setOfReactions.getReaction(k).getProducts().getMolecule(j);
                if (!existAC(setOfMol, product)) {
                  setOfMol.addMolecule(product);
                  countStructure++;
                  if (countStructure > maxStructures) return setOfMol;
                }
              }
        } catch (CDKException e) {
          e.printStackTrace();
        }
      }
    }
    return setOfMol;
  }
  /**
   * Get the container which is found resonance from a IMolecule. It is based on looking if the
   * order of the bond changes.
   *
   * @param molecule The IMolecule to analyze
   * @return The different containers
   */
  @TestMethod("testGetContainers_IMolecule")
  public IAtomContainerSet getContainers(IMolecule molecule) {
    IAtomContainerSet setOfCont = molecule.getBuilder().newAtomContainerSet();
    IMoleculeSet setOfMol = getStructures(molecule);

    if (setOfMol.getMoleculeCount() == 0) return setOfCont;

    /*extraction of all bonds which has been produced a changes of order*/
    List<IBond> bondList = new ArrayList<IBond>();
    for (int i = 1; i < setOfMol.getMoleculeCount(); i++) {
      IMolecule mol = setOfMol.getMolecule(i);
      for (int j = 0; j < mol.getBondCount(); j++) {
        IBond bond = molecule.getBond(j);
        if (!mol.getBond(j).getOrder().equals(bond.getOrder())) {
          if (!bondList.contains(bond)) bondList.add(bond);
        }
      }
    }

    if (bondList.size() == 0) return null;

    int[] flagBelonging = new int[bondList.size()];
    for (int i = 0; i < flagBelonging.length; i++) flagBelonging[i] = 0;
    int[] position = new int[bondList.size()];
    int maxGroup = 1;

    /*Analysis if the bond are linked together*/
    List<IBond> newBondList = new ArrayList<IBond>();
    newBondList.add(bondList.get(0));

    int pos = 0;
    for (int i = 0; i < newBondList.size(); i++) {

      if (i == 0) flagBelonging[i] = maxGroup;
      else {
        if (flagBelonging[position[i]] == 0) {
          maxGroup++;
          flagBelonging[position[i]] = maxGroup;
        }
      }

      IBond bondA = newBondList.get(i);
      for (int ato = 0; ato < 2; ato++) {
        IAtom atomA1 = bondA.getAtom(ato);
        List<IBond> bondA1s = molecule.getConnectedBondsList(atomA1);
        for (int j = 0; j < bondA1s.size(); j++) {
          IBond bondB = bondA1s.get(j);
          if (!newBondList.contains(bondB))
            for (int k = 0; k < bondList.size(); k++)
              if (bondList.get(k).equals(bondB))
                if (flagBelonging[k] == 0) {
                  flagBelonging[k] = maxGroup;
                  pos++;
                  newBondList.add(bondB);
                  position[pos] = k;
                }
        }
      }
      // if it is final size and not all are added
      if (newBondList.size() - 1 == i)
        for (int k = 0; k < bondList.size(); k++)
          if (!newBondList.contains(bondList.get(k))) {
            newBondList.add(bondList.get(k));
            position[i + 1] = k;
            break;
          }
    }
    /*creating containers according groups*/
    for (int i = 0; i < maxGroup; i++) {
      IAtomContainer container = molecule.getBuilder().newAtomContainer();
      for (int j = 0; j < bondList.size(); j++) {
        if (flagBelonging[j] != i + 1) continue;
        IBond bond = bondList.get(j);
        IAtom atomA1 = bond.getAtom(0);
        IAtom atomA2 = bond.getAtom(1);
        if (!container.contains(atomA1)) container.addAtom(atomA1);
        if (!container.contains(atomA2)) container.addAtom(atomA2);
        container.addBond(bond);
      }
      setOfCont.addAtomContainer(container);
    }
    return setOfCont;
  }