public static List<SSBondImpl> getSsBondListFromBondList(List<Bond> bonds) { List<SSBondImpl> l = new ArrayList<>(); for (int i=0; i<bonds.size(); i++) { SSBondImpl ssbond = toSsBond(bonds.get(i)); ssbond.setSerNum(i + 1); l.add(ssbond); } return l; }