mybaits踩坑：返回的实体类是一个list

我们发现，当xml文件设置返回值类型为实体类时，会默认查询结果是一个list,此时mapper 中的接口应该使用list接受，如果使用单个对象接受会报错：

List<GoodsVo> findGoodsVo(); 
GoodsVo findGoodsVoByGoodsId(Long GoodsId);//报错

<select id="findGoodsVo" resultMap="goodsVoMap">
    select
      g.id,g.goods_name,g.goods_img,g.goods_detail,g.goods_price,g.goods_stock,
      sg.seckill_price,sg.stock_count,sg.start_date,sg.end_date
    from
      t_goods g
        LEFT JOIN
      t_seckill_goods as sg on g.id=sg.goods_id
  </select>

  <select id="findGoodsVoByGoodsId" resultMap="goodsVoMap" >
    select distinct
      g.id,g.goods_name,g.goods_img,g.goods_detail,g.goods_price,g.goods_stock,
      sg.seckill_price,sg.stock_count,sg.start_date,sg.end_date
    from
      t_goods g
        LEFT JOIN
      t_seckill_goods as sg on g.id=sg.goods_id
    where
      g.id = #{goodsId}
  </select>