code: private Set<OrderBy> copyOrderingSet() {
      Set<OrderBy> orderingCopy = Sets.newLinkedHashSet();
      for (OrderBy order : this.ordering) {
        OrderBy copyOrder = new OrderBy();
        copyOrder.setField(order.getField());
        copyOrder.setSortOrder(order.getSortOrder());
        orderingCopy.add(copyOrder);
      }
      return orderingCopy;
    }
docs: Copies the whole set of OrderBy objects, by creating new instances of each one in the given
  set.
  
  @return the new set of OrderBy objects with different instance for each of the OrderBy