code: public static IBond.Order convertOrder(double srcOrder) {
          if (srcOrder > 3.5) {
              return Order.QUADRUPLE;
          }
          if (srcOrder > 2.5) {
              return Order.TRIPLE;
          }
          if (srcOrder > 1.5) {
              return Order.DOUBLE;
          }
          if (srcOrder > 0.5) {
              return Order.SINGLE;
          }
          return null;
      }
docs: Get bond order value as {@link Order}.
  
  @param  srcOrder numerical bond order
  @return          the bond order type for the given numerical bond order