The return type is incompatible with ImanagerDao.findOrderInfo(int)错误

Question

       public Map<Order,Items[]> findOrderInfo(int id){  //将多表查询信息的一记录封装到一个map中

      CustomerDaoImp cdi =new CustomerDaoImp();

      Map<Order,Items[]> map = new HashMap<Order,Items[]>(20);

      Order order =new Order();   //封装订单的头信息

      Items[] its  = new Items[20];     //数组装有多个商品，及对应数量。Items有fg，和count属性对应商品和数量

      try {

PreparedStatement pst =   DbConn.getConnection().prepareStatement("select * from order_info o join Order_goods_1 g on o.id=g.id where o.id=?");

    pst.setInt(1, id);

    ResultSet rs =pst.executeQuery();

    if(rs.next()){

    order.setOnum(rs.getString("onum"));

    order.setOname(rs.getString("oname"));

    order.setOcardnum(rs.getString("ocardnum"));

    order.setOaddr(rs.getString("oaddr"));

    order.setOphone(rs.getString("ophone"));

    order.setCost(rs.getInt("cost"));

    order.setTime(rs.getTimestamp("crea_at"));

    order.setInfo(rs.getString("oinfo"));

    for (int i = 1; i < its.length+1; i++) { //此循环获取数量不是0的商品

Items it =new Items();

byte m =rs.getByte("goods"+i);

it.setCount(m);

if(m>0){

int j =0;

it.getFg().setName(cdi.findNameById(i));

it.getFg().setPrice(cdi.findPriceById(i));

it.getFg().setSpec(cdi.findSpecById(i));

its[j]=it;

j++;

}

}

    map.put(order, its); 

    }

      } catch (SQLException e) {

System.out.println("com.jdc.dao.ManagerDao.java");

}

      return map;

       }

}