code: public static boolean isLowerOrder(IBond.Order first, IBond.Order second) {
          if (first == null || second == null ||
              first == IBond.Order.UNSET || second == IBond.Order.UNSET) return false;
          return first.compareTo(second) < 0;
      }
docs: Returns true if the first bond has a lower bond order than the second bond.
  It returns false if the bond order is equal, and if the order of the first
  bond is larger than that of the second. Also returns false if either bond
  order is unset.
  
  @param first  The first bond order object
  @param second The second bond order object
  @return true if the first bond order is lower than the second one, false otherwise
  @see #isHigherOrder(org.openscience.cdk.interfaces.IBond.Order, org.openscience.cdk.interfaces.IBond.Order)