为什么要把插入图片的操作单独作为一步？为什么不和店铺的enableStatus，createTime，lastEditTime一起赋值，然后同时做添加店铺信息操作？

    try {
            // 给店铺信息赋初始值
            shop.setEnableStatus(0);//未上架在审核中
            shop.setCreateTime(new Date());//创建时间
            shop.setLastEditTime(new Date());//上一次修改的时间
            // 添加店铺信息
            int effectedNum = shopDao.insertShop(shop);
            if (effectedNum < 0) {
                throw new RuntimeException("店铺创建失败");
            } else {
                if (shopImg != null) {
                    // 存储图片
                    try {
                        addShopImg(shop, shopImg);
                    } catch (Exception e) {
                        throw new RuntimeException("addShopImg error:" + e.getMessage());
                    }
                    // 更新店铺的图片地址
                    effectedNum = shopDao.updateShop(shop);
                    if (effectedNum < 0) {
                        throw new RuntimeException("更新图片地址失败");
                    }
                }
            }
        } catch (Exception e) {
            throw new RuntimeException("addshop error:" + e.getMessage());
        }