java - Spring RowMapper NullPointerException

Question

我尝试四处寻找问题的答案，但未能解决。

我的应用程序在第 46 行的 RowMapper 类中抛出 NPE:

orderLineRepository.sqlGetOrderLinesForOrder(rs.getInt("orderId"))

有人可以帮我解决这个问题吗？我不太确定它出了什么问题。

这是类(class)的副本:

@Repository("orderRepository")
public class OrderRepository {

    @Autowired
    private JdbcTemplate jdbc;

    public Order sqlGetOrderByOrderId(int orderId) {
        String sql = "SELECT om.orderId, om.orderRef, om.orderChannel, "
                + "om.orderCreated, om.orderCompleted, om.orderStatus, "
                + "c.customerId, c.name, c.email, c.phoneNumber, "
                + "a.addressId, a.houseNameNumber, a.streetName, "
                + "a.addressLine2, a.addressLine3, a.addressLine4, "
                + "a.postCode, a.countryCode "
                + "FROM OrderMain om "
                + "INNER JOIN Customer c ON om.customerId=c.customerId "
                + "INNER JOIN Address a ON om.addressId=a.addressId "
                + "WHERE om.orderId=?";

        return jdbc.queryForObject(sql, new Object[] {orderId}, new OrderRowMapper());
    }

}

订单行映射器:

public class OrderRowMapper implements RowMapper<Order> {

    @Autowired
    private OrderLineRepository orderLineRepository;

    public Order mapRow(ResultSet rs, int rowNum) throws SQLException {
        Customer customer = new Customer();
        customer.setCustomerId(rs.getInt("customerId"));
        customer.setName(rs.getString("name"));
        customer.setEmail(rs.getString("email"));
        customer.setPhoneNumber(rs.getString("phoneNumber"));

        Address address = new Address();
        address.setAddressId(rs.getInt("addressId"));
        address.setHouseNameNumber(rs.getString("houseNameNumber"));
        address.setStreetName(rs.getString("streetName"));
        address.setAddressLine2(rs.getString("addressLine2"));
        address.setAddressLine3(rs.getString("addressLine3"));
        address.setAddressLine4(rs.getString("addressLine4"));
        address.setPostcode(rs.getString("postcode"));
        address.setCountryCode(rs.getString("countryCode"));

        Order order = new Order(
                    rs.getInt("orderId"),
                    rs.getString("orderRef"),
                    rs.getString("orderChannel"),
                    rs.getTimestamp("orderCreated"),
                    rs.getTimestamp("orderCompleted"),
                    OrderStatus.orderStatusGetById(rs.getInt("orderStatus")),
                    customer,
                    address,
                    orderLineRepository.sqlGetOrderLinesForOrder(rs.getInt("orderId"))
                );

        return order;
    }

}

这正在调用我的 orderLineRepository，如下:

@Repository("orderLineRepository")
public class OrderLineRepository {

    @Autowired
    private JdbcTemplate jdbc;

    @Autowired
    private NamedParameterJdbcTemplate namedJdbc;

    public List<OrderLine> sqlGetOrderLinesForOrder(int orderId) {
        Map<String, Object> params = new HashMap<String, Object>();
        params.put("orderId", orderId);

        String sql = "SELECT itemId, orderQty, cancelledQty, "
                + "despatchedQty, replacedQty, refundedQty, "
                + "orderLineStatus, orderValue, unitValue, "
                + "shippingCost "
                + "FROM OrderLine "
                + "WHERE orderId=:orderId";

        return namedJdbc.query(sql, params, new OrderLineRowMapper());
    }

    public List<OrderLine> sqlGetAllOrderLines() {
        String sql = "SELECT itemId, orderQty, cancelledQty, "
                + "despatchedQty, replacedQty, refundedQty, "
                + "orderLineStatus, orderValue, unitValue, "
                + "shippingCost "
                + "FROM OrderLine";

        return jdbc.query(sql, new OrderLineRowMapper());
    }

}

如果需要，这是我的 OrderLineRowMapper:

public class OrderLineRowMapper implements RowMapper<OrderLine> {

    public OrderLine mapRow(ResultSet rs, int rowNum) throws SQLException {
        OrderLine orderLine = new OrderLine();
             orderLine.setItemId(rs.getInt("itemId"));
             orderLine.setOrderQty(rs.getInt("orderQty"));
             orderLine.setCancelledQty(rs.getInt("cancelledQty"));
             orderLine.setDespatchedQty(rs.getInt("despatchedQty"));
             orderLine.setReplacedQty(rs.getInt("replacedQty"));
             orderLine.setRefundedQty(rs.getInt("refundedQty"));
             orderLine.setOrderLineStatus(OrderLineStatus.orderLineStatusGetById(rs.getInt("orderLineStatus")));
             orderLine.setOrderValue(rs.getDouble("orderValue"));
             orderLine.setUnitValue(rs.getDouble("unitValue"));
             orderLine.setShippingCost(rs.getDouble("shippingCost"));
        return orderLine;
    }

}

预先感谢您提供的任何帮助!

Answer 1

当您自己创建对象时，您如何期望 Spring Autowiring 任何内容？

return namedJdbc.query(sql, params, new OrderLineRowMapper());

Spring 只能将 Bean 注入(inject)到其他 Spring 管理的 Bean 中。

让 Spring 创建一个 OrderLineRowMapper bean 并注入(inject)并在您的 OrderLineRepository 类中使用它。