Mongo 排序，多个字段排序

Mongo 排序，多个字段排序

Sort sort = null;List<Order> orderList = new ArrayList<Order>();if (StringUtils.isNotBlank(req.getOrderTag()) && StringUtils.isNotBlank(req.getOrderDirection())) {    if("ASC".equalsIgnoreCase(req.getOrderDirection())){Order orderCurrentPrice = new Order(Direction.ASC, req.getOrderTag());orderList.add(orderCurrentPrice);    }else{Order orderCurrentPrice = new Order(Direction.DESC, req.getOrderTag());orderList.add(orderCurrentPrice);    }} else {    Order orderCurrentPrice = new Order(Direction.DESC, "createDate");    orderList.add(orderCurrentPrice);}Order orderCurrentPrice = new Order(Direction.ASC, "id");orderList.add(orderCurrentPrice);sort = new Sort(orderList);