遍历rg的时候出错了 错误信息如下java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to org.nutz.lang.util.NutMap

  @At("/list")
    @Ok("json:{ignoreNull:false}")
    public Object list(@Param("id") String id,
                       @Param("state") String state){
        List<NutMap> reg = new ArrayList<>();
        List<NutMap> rg = new ArrayList<NutMap>();
        try {
            if(state!=null){
                Sql rg_sql = dao.sqls().create("return_good_state.list");
                rg_sql.params().set("uid", id);
                rg_sql.params().set("state", id);
                rg = appReturnGoodService.listMap(rg_sql);
            }else {
                Sql rg_sql = dao.sqls().create("return_good.list");
                rg_sql.params().set("uid", id);
                rg = appReturnGoodService.listMap(rg_sql);
            }
            String ret_id = null;
            if(rg.size() > 0){
                for(NutMap r :rg){
                    ret_id = r.getString("id");
                    if(ret_id!=null){
                        Sql sql = dao.sqls().create("return_item.list");
                        sql.params().set("ret_id", ret_id);
                        List<NutMap> rg_item = appReturnGoodService.listMap(sql);
                        r.addv("items",rg_item);
                        reg.add(r);
                    }
                }
            }
            if(reg.size() > 0){
                return ResultApp.success("请求成功",reg);
            } else {
                return ResultApp.success("02","无退货商品",reg);
            }
        } catch (Exception e) {
            System.out.print(e.toString());
            return ResultApp.error("请求失败");
        }
    }