### Question:
OrderDao { public OrderDO selectById(Integer id) { return template.queryForObject("SELECT id, user_id FROM orders WHERE id = ?", new BeanPropertyRowMapper<>(OrderDO.class), id); }  OrderDO selectById(Integer id);  }### Answer:
@Test public void testSelectById() { OrderDO order = orderDao.selectById(1); System.out.println(order); }