外卖小程序07

需求一

实现用户下单功能,微信小程序用户通过购物车去支付按钮下单

代码实现

Controller层

OrderController

@RestController("userOrderController")
@RequestMapping("user/order")
@Api(tags = "用户端订单相关接口")
@Slf4j
public class OrderController {

    @Autowired
    private OrderService orderService;

    /**
     * 用户下单
     *
     * @param orderSubmitDTO
     * @return
     */
    @PostMapping("submit")
    @ApiOperation("用户下单")
    public Result<OrderSubmitVO> submit(@RequestBody OrdersSubmitDTO orderSubmitDTO) {
        log.info("用户下单,参数为:{}", orderSubmitDTO);
        OrderSubmitVO ordersubmit = orderService.ordersubmit(orderSubmitDTO);
        return Result.success(ordersubmit);
    }
}

Service层

OrderService

package com.sky.service;

import com.sky.dto.OrdersPaymentDTO;
import com.sky.dto.OrdersSubmitDTO;
import com.sky.vo.OrderPaymentVO;
import com.sky.vo.OrderSubmitVO;

public interface OrderService {
    /**
     * 用户下单
     *
     * @param orderSubmitVO
     * @return
     */
    OrderSubmitVO ordersubmit(OrdersSubmitDTO orderSubmitVO);

    /**
     * 订单支付
     *
     * @param ordersPaymentDTO
     * @return
     */
    OrderPaymentVO payment(OrdersPaymentDTO ordersPaymentDTO) throws Exception;

    /**
     * 支付成功，修改订单状态
     *
     * @param outTradeNo
     */
    void paySuccess(String outTradeNo);
}

OrderServiceImpl

@Service
public class OrderServiceImpl implements OrderService {

    @Autowired
    private OrderMapper orderMapper;
    @Autowired
    private OrderDetailMapper orderDetailMapper;
    @Autowired
    private AddressBookMapper addressBookMapper;
    @Autowired
    private ShoppingCartMapper shoppingCartMapper;

    @Override
    @Transactional
    public OrderSubmitVO ordersubmit(OrdersSubmitDTO ordersSubmitDTO) {
        //处理业务异常(地址簿为空,购物车为空),前端和后端都应作此校验,以保证代码的健壮性
        Long addressBookId = ordersSubmitDTO.getAddressBookId();
        AddressBook addressBook = addressBookMapper.getById(addressBookId);
        //判断地址簿是否为空
        if (addressBook == null) {
            throw new OrderBusinessException(MessageConstant.ADDRESS_BOOK_IS_NULL);
        }

        Long userId = BaseContext.getCurrentId();
        ShoppingCart shoppingCart = ShoppingCart.builder().userId(userId).build();
        List<ShoppingCart> shoppingCartList = shoppingCartMapper.list(shoppingCart);
        //判断购物车是否为空
        if (shoppingCartList == null || shoppingCartList.size() == 0) {
            throw new OrderBusinessException(MessageConstant.SHOPPING_CART_IS_NULL);
        }

        //向订单表中插入一条数据
        Orders orders = new Orders();
        BeanUtils.copyProperties(ordersSubmitDTO, orders);
        orders.setNumber(String.valueOf(System.currentTimeMillis()));
        orders.setStatus(Orders.PENDING_PAYMENT);
        orders.setUserId(userId);
        orders.setOrderTime(LocalDateTime.now());
        orders.setPayStatus(Orders.UN_PAID);
        orders.setPhone(addressBook.getPhone());
        orders.setAddress(addressBook.getDetail());
        orders.setConsignee(addressBook.getConsignee());

        orderMapper.insert(orders);

        ArrayList<OrderDetail> orderDetails = new ArrayList<>();
        //向订单详情表中插入n条数据
        for (ShoppingCart cart : shoppingCartList) {
            OrderDetail orderDetail = new OrderDetail();
            BeanUtils.copyProperties(cart, orderDetail);
            orderDetail.setOrderId(orders.getId());
            orderDetails.add(orderDetail);
        }
        orderDetailMapper.insertBatch(orderDetails);

        //清空购物车数据
        shoppingCartMapper.deleteByUserId(userId);

        //封装OrderSubmitVO数据
        OrderSubmitVO orderSubmitVO = OrderSubmitVO.builder()
                .id(orders.getId())
                .orderTime(orders.getOrderTime())
                .orderAmount(orders.getAmount())
                .orderNumber(orders.getNumber())
                .build();
        return orderSubmitVO;
    }
}

Mapper层

AddressBookMapper

@Mapper
public interface AddressBookMapper {
    /**
     * 根据id查询
     * @param id
     * @return
     */
    @Select("select * from address_book where id = #{id}")
    AddressBook getById(Long id);
}

ShoppingCartMapper

@Mapper
public interface ShoppingCartMapper {
    /**
     * 动态条件查询购物车
     *
     * @param shoppingCart
     * @return
     */
    List<ShoppingCart> list(ShoppingCart shoppingCart);
    
    /**
     * 根据用户id删除购物车数据
     *
     * @param userId
     */
    @Delete("delete from shopping_cart where user_id = #{userId}")
    void deleteByUserId(Long userId);
}

ShoppingCartMapper.xml

DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.sky.mapper.ShoppingCartMapper">
    <select id="list" resultType="com.sky.entity.ShoppingCart">
        select *
        from shopping_cart
        <where>
            <if test="userId!=null">
                and user_id = #{userId}
            if>
            <if test="dishId != null">
                and dish_id = #{dishId}
            if>
            <if test="setmealId != null">
                and setmeal_id = #{setmealId}
            if>
            <if test="dishFlavor">
                and dish_flavor = #{dishFlavor}
            if>
        where>
    select>
mapper>

OrderMapper

@Mapper
public interface OrderMapper {

    /**
     * 插入订单数据
     *
     * @param orders
     */
    void insert(Orders orders);

}

OrderDetailMapper

@Mapper
public interface OrderDetailMapper {

    void insertBatch(ArrayList<OrderDetail> orderDetails);
}

实体类

OrderSubmitDTO

@Data
public class OrdersSubmitDTO implements Serializable {
    //地址簿id
    private Long addressBookId;
    //付款方式
    private int payMethod;
    //备注
    private String remark;
    //预计送达时间
    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd HH:mm:ss")
    private LocalDateTime estimatedDeliveryTime;
    //配送状态  1立即送出  0选择具体时间
    private Integer deliveryStatus;
    //餐具数量
    private Integer tablewareNumber;
    //餐具数量状态  1按餐量提供  0选择具体数量
    private Integer tablewareStatus;
    //打包费
    private Integer packAmount;
    //总金额
    private BigDecimal amount;
}

AddressBook

/**
 * 地址簿
 */
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class AddressBook implements Serializable {

    private static final long serialVersionUID = 1L;

    private Long id;

    //用户id
    private Long userId;

    //收货人
    private String consignee;

    //手机号
    private String phone;

    //性别 0 女 1 男
    private String sex;

    //省级区划编号
    private String provinceCode;

    //省级名称
    private String provinceName;

    //市级区划编号
    private String cityCode;

    //市级名称
    private String cityName;

    //区级区划编号
    private String districtCode;

    //区级名称
    private String districtName;

    //详细地址
    private String detail;

    //标签
    private String label;

    //是否默认 0否 1是
    private Integer isDefault;
}

ShoppingCart

/**
 * 购物车
 */
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class ShoppingCart implements Serializable {

    private static final long serialVersionUID = 1L;

    private Long id;

    //名称
    private String name;

    //用户id
    private Long userId;

    //菜品id
    private Long dishId;

    //套餐id
    private Long setmealId;

    //口味
    private String dishFlavor;

    //数量
    private Integer number;

    //金额
    private BigDecimal amount;

    //图片
    private String image;

    private LocalDateTime createTime;
}

Orders

/**
 * 订单
 */
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class Orders implements Serializable {

    /**
     * 订单状态 1待付款 2待接单 3已接单 4派送中 5已完成 6已取消
     */
    public static final Integer PENDING_PAYMENT = 1;
    public static final Integer TO_BE_CONFIRMED = 2;
    public static final Integer CONFIRMED = 3;
    public static final Integer DELIVERY_IN_PROGRESS = 4;
    public static final Integer COMPLETED = 5;
    public static final Integer CANCELLED = 6;

    /**
     * 支付状态 0未支付 1已支付 2退款
     */
    public static final Integer UN_PAID = 0;
    public static final Integer PAID = 1;
    public static final Integer REFUND = 2;

    private static final long serialVersionUID = 1L;

    private Long id;

    //订单号
    private String number;

    //订单状态 1待付款 2待接单 3已接单 4派送中 5已完成 6已取消 7退款
    private Integer status;

    //下单用户id
    private Long userId;

    //地址id
    private Long addressBookId;

    //下单时间
    private LocalDateTime orderTime;

    //结账时间
    private LocalDateTime checkoutTime;

    //支付方式 1微信，2支付宝
    private Integer payMethod;

    //支付状态 0未支付 1已支付 2退款
    private Integer payStatus;

    //实收金额
    private BigDecimal amount;

    //备注
    private String remark;

    //用户名
    private String userName;

    //手机号
    private String phone;

    //地址
    private String address;

    //收货人
    private String consignee;

    //订单取消原因
    private String cancelReason;

    //订单拒绝原因
    private String rejectionReason;

    //订单取消时间
    private LocalDateTime cancelTime;

    //预计送达时间
    private LocalDateTime estimatedDeliveryTime;

    //配送状态  1立即送出  0选择具体时间
    private Integer deliveryStatus;

    //送达时间
    private LocalDateTime deliveryTime;

    //打包费
    private int packAmount;

    //餐具数量
    private int tablewareNumber;

    //餐具数量状态  1按餐量提供  0选择具体数量
    private Integer tablewareStatus;
}

OrderDetail

/**
 * 订单明细
 */
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class OrderDetail implements Serializable {

    private static final long serialVersionUID = 1L;

    private Long id;

    //名称
    private String name;

    //订单id
    private Long orderId;

    //菜品id
    private Long dishId;

    //套餐id
    private Long setmealId;

    //口味
    private String dishFlavor;

    //数量
    private Integer number;

    //金额
    private BigDecimal amount;

    //图片
    private String image;
}

需求二

实现订单支付功能,用户通过微信小程序支付

注意:要实现微信支付就需要注册微信支付的一个商户号，这个商户号是必须要有一家企业并且有正规的营业执照。只有具备了这些资质之后，才可以去注册商户号，才能开通支付权限。

微信支付准备工作

如何保证数据安全？

完成微信支付有两个关键的步骤：

第一个就是需要在商户系统当中调用微信后台的一个下单接口，就是生成预支付交易单。

第二个就是支付成功之后微信后台会给推送消息。

这两个接口数据的安全性，要求其实是非常高的。

**解决：**微信提供的方式就是对数据进行加密、解密、签名多种方式。要完成数据加密解密，需要提前准备相应的一些文件，其实就是一些证书。

获取微信支付平台证书、商户私钥文件：

apiclient_key.pem

wechatpay_1111111111111111111.pem

在后绪程序开发过程中，就会使用到这两个文件，需要提前把这两个文件准备好。

如何调用到商户系统？

微信后台会调用到商户系统给推送支付的结果，在这里我们就会遇到一个问题，就是微信后台怎么就能调用到我们这个商户系统呢？因为这个调用过程，其实本质上也是一个HTTP请求。

目前，商户系统它的ip地址就是当前自己电脑的ip地址，只是一个局域网内的ip地址，微信后台无法调用到。

解决：内网穿透。通过cpolar软件可以获得一个临时域名，而这个临时域名是一个公网ip，这样，微信后台就可以请求到商户系统了。

cpolar软件的使用：

1). 下载与安装

下载地址：https://dashboard.cpolar.com/get-started

2). cpolar指定authtoken

在官网获取authtoken,在安装目录下执行命令

cpolar.exe authtoken xxxxxxxxxxxxxxxxxxxxxxxx

3).在安装目录下使用cpolar.exe http 端口号(eg:cpolar.exe http 8080)命令获取临时公网地址即可

微信小程序支付时序图

代码实现

Controller层

OrderController

@RestController("userOrderController")
@RequestMapping("user/order")
@Api(tags = "用户端订单相关接口")
@Slf4j
public class OrderController {

    @Autowired
    private OrderService orderService;

    /**
     * 用户下单
     *
     * @param orderSubmitDTO
     * @return
     */
    @PostMapping("submit")
    @ApiOperation("用户下单")
    public Result<OrderSubmitVO> submit(@RequestBody OrdersSubmitDTO orderSubmitDTO) {
        log.info("用户下单,参数为:{}", orderSubmitDTO);
        OrderSubmitVO ordersubmit = orderService.ordersubmit(orderSubmitDTO);
        return Result.success(ordersubmit);
    }

    /**
     * 订单支付
     *
     * @param ordersPaymentDTO
     * @return
     */
    @PutMapping("/payment")
    @ApiOperation("订单支付")
    public Result<OrderPaymentVO> payment(@RequestBody OrdersPaymentDTO ordersPaymentDTO) throws Exception {
        log.info("订单支付：{}", ordersPaymentDTO);
        OrderPaymentVO orderPaymentVO = orderService.payment(ordersPaymentDTO);
        log.info("生成预支付交易单：{}", orderPaymentVO);
        return Result.success(orderPaymentVO);
    }
}

PayNotifyController

/**
 * 支付回调相关接口
 */
@RestController
@RequestMapping("/notify")
@Slf4j
public class PayNotifyController {
    @Autowired
    private OrderService orderService;
    @Autowired
    private WeChatProperties weChatProperties;

    /**
     * 支付成功回调
     *
     * @param request
     */
    @RequestMapping("/paySuccess")
    public void paySuccessNotify(HttpServletRequest request, HttpServletResponse response) throws Exception {
        //读取数据
        String body = readData(request);
        log.info("支付成功回调：{}", body);

        //数据解密
        String plainText = decryptData(body);
        log.info("解密后的文本：{}", plainText);

        JSONObject jsonObject = JSON.parseObject(plainText);
        String outTradeNo = jsonObject.getString("out_trade_no");//商户平台订单号
        String transactionId = jsonObject.getString("transaction_id");//微信支付交易号

        log.info("商户平台订单号：{}", outTradeNo);
        log.info("微信支付交易号：{}", transactionId);

        //业务处理，修改订单状态、来单提醒
        orderService.paySuccess(outTradeNo);

        //给微信响应
        responseToWeixin(response);
    }

    /**
     * 读取数据
     *
     * @param request
     * @return
     * @throws Exception
     */
    private String readData(HttpServletRequest request) throws Exception {
        BufferedReader reader = request.getReader();
        StringBuilder result = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            if (result.length() > 0) {
                result.append("\n");
            }
            result.append(line);
        }
        return result.toString();
    }

    /**
     * 数据解密
     *
     * @param body
     * @return
     * @throws Exception
     */
    private String decryptData(String body) throws Exception {
        JSONObject resultObject = JSON.parseObject(body);
        JSONObject resource = resultObject.getJSONObject("resource");
        String ciphertext = resource.getString("ciphertext");
        String nonce = resource.getString("nonce");
        String associatedData = resource.getString("associated_data");

        AesUtil aesUtil = new AesUtil(weChatProperties.getApiV3Key().getBytes(StandardCharsets.UTF_8));
        //密文解密
        String plainText = aesUtil.decryptToString(associatedData.getBytes(StandardCharsets.UTF_8),
                nonce.getBytes(StandardCharsets.UTF_8),
                ciphertext);

        return plainText;
    }

    /**
     * 给微信响应
     * @param response
     */
    private void responseToWeixin(HttpServletResponse response) throws Exception{
        response.setStatus(200);
        HashMap<Object, Object> map = new HashMap<>();
        map.put("code", "SUCCESS");
        map.put("message", "SUCCESS");
        response.setHeader("Content-type", ContentType.APPLICATION_JSON.toString());
        response.getOutputStream().write(JSONUtils.toJSONString(map).getBytes(StandardCharsets.UTF_8));
        response.flushBuffer();
    }
}

Service层

OrderService

public interface OrderService {
    /**
     * 用户下单
     *
     * @param orderSubmitVO
     * @return
     */
    OrderSubmitVO ordersubmit(OrdersSubmitDTO orderSubmitVO);

    /**
     * 订单支付
     *
     * @param ordersPaymentDTO
     * @return
     */
    OrderPaymentVO payment(OrdersPaymentDTO ordersPaymentDTO) throws Exception;

    /**
     * 支付成功，修改订单状态
     *
     * @param outTradeNo
     */
    void paySuccess(String outTradeNo);
}

OrderServiceImpl

@Service
public class OrderServiceImpl implements OrderService {

    @Autowired
    private OrderMapper orderMapper;
    @Autowired
    private OrderDetailMapper orderDetailMapper;
    @Autowired
    private AddressBookMapper addressBookMapper;
    @Autowired
    private ShoppingCartMapper shoppingCartMapper;
    @Autowired
    private UserMapper userMapper;
    @Autowired
    private WeChatPayUtil weChatPayUtil;

    @Override
    @Transactional
    public OrderSubmitVO ordersubmit(OrdersSubmitDTO ordersSubmitDTO) {
        //处理业务异常(地址簿为空,购物车为空),前端和后端都应作此校验,以保证代码的健壮性
        Long addressBookId = ordersSubmitDTO.getAddressBookId();
        AddressBook addressBook = addressBookMapper.getById(addressBookId);
        //判断地址簿是否为空
        if (addressBook == null) {
            throw new OrderBusinessException(MessageConstant.ADDRESS_BOOK_IS_NULL);
        }

        Long userId = BaseContext.getCurrentId();
        ShoppingCart shoppingCart = ShoppingCart.builder().userId(userId).build();
        List<ShoppingCart> shoppingCartList = shoppingCartMapper.list(shoppingCart);
        //判断购物车是否为空
        if (shoppingCartList == null || shoppingCartList.size() == 0) {
            throw new OrderBusinessException(MessageConstant.SHOPPING_CART_IS_NULL);
        }

        //向订单表中插入一条数据
        Orders orders = new Orders();
        BeanUtils.copyProperties(ordersSubmitDTO, orders);
        orders.setNumber(String.valueOf(System.currentTimeMillis()));
        orders.setStatus(Orders.PENDING_PAYMENT);
        orders.setUserId(userId);
        orders.setOrderTime(LocalDateTime.now());
        orders.setPayStatus(Orders.UN_PAID);
        orders.setPhone(addressBook.getPhone());
        orders.setAddress(addressBook.getDetail());
        orders.setConsignee(addressBook.getConsignee());

        orderMapper.insert(orders);

        ArrayList<OrderDetail> orderDetails = new ArrayList<>();
        //向订单详情表中插入n条数据
        for (ShoppingCart cart : shoppingCartList) {
            OrderDetail orderDetail = new OrderDetail();
            BeanUtils.copyProperties(cart, orderDetail);
            orderDetail.setOrderId(orders.getId());
            orderDetails.add(orderDetail);
        }
        orderDetailMapper.insertBatch(orderDetails);

        //清空购物车数据
        shoppingCartMapper.deleteByUserId(userId);

        //封装OrderSubmitVO数据
        OrderSubmitVO orderSubmitVO = OrderSubmitVO.builder()
                .id(orders.getId())
                .orderTime(orders.getOrderTime())
                .orderAmount(orders.getAmount())
                .orderNumber(orders.getNumber())
                .build();
        return orderSubmitVO;
    }

    /**
     * 订单支付
     *
     * @param ordersPaymentDTO
     * @return
     */
    @Override
    public OrderPaymentVO payment(OrdersPaymentDTO ordersPaymentDTO) throws Exception {
        // 当前登录用户id
        Long userId = BaseContext.getCurrentId();
        User user = userMapper.getById(userId);

        //调用微信支付接口，生成预支付交易单
        JSONObject jsonObject = weChatPayUtil.pay(
                ordersPaymentDTO.getOrderNumber(), //商户订单号
                new BigDecimal(0.01), //支付金额，单位 元
                "苍穹外卖订单", //商品描述
                user.getOpenid() //微信用户的openid
        );

        if (jsonObject.getString("code") != null && jsonObject.getString("code").equals("ORDERPAID")) {
            throw new OrderBusinessException("该订单已支付");
        }

        OrderPaymentVO vo = jsonObject.toJavaObject(OrderPaymentVO.class);
        vo.setPackageStr(jsonObject.getString("package"));

        return vo;
    }

    /**
     * 支付成功，修改订单状态
     *
     * @param outTradeNo
     */
    @Override
    public void paySuccess(String outTradeNo) {
        // 当前登录用户id
        Long userId = BaseContext.getCurrentId();

        // 根据订单号查询当前用户的订单
        Orders ordersDB = orderMapper.getByNumberAndUserId(outTradeNo, userId);

        // 根据订单id更新订单的状态、支付方式、支付状态、结账时间
        Orders orders = Orders.builder()
                .id(ordersDB.getId())
                .status(Orders.TO_BE_CONFIRMED)
                .payStatus(Orders.PAID)
                .checkoutTime(LocalDateTime.now())
                .build();

        orderMapper.update(orders);
    }
}

Mapper层

UserMapper

@Mapper
public interface UserMapper {
    /**
     * 根据id查询用户
     *
     * @param userId
     * @return
     */
    @Select("select * from user where id = #{id}")
    User getById(Long userId);
}

OrderMapper

package com.sky.mapper;

import com.sky.entity.Orders;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

@Mapper
public interface OrderMapper {

    /**
     * 插入订单数据
     *
     * @param orders
     */
    void insert(Orders orders);

    /**
     * 根据订单号和用户id查询订单
     *
     * @param orderNumber
     * @param userId
     */
    @Select("select * from orders where number = #{orderNumber} and user_id= #{userId}")
    Orders getByNumberAndUserId(String orderNumber, Long userId);

    /**
     * 修改订单信息
     *
     * @param orders
     */
    void update(Orders orders);
}

工具类

WeChatPayUtil

/**
 * 微信支付工具类
 */
@Component
public class WeChatPayUtil {

    //微信支付下单接口地址
    public static final String JSAPI = "https://api.mch.weixin.qq.com/v3/pay/transactions/jsapi";

    //申请退款接口地址
    public static final String REFUNDS = "https://api.mch.weixin.qq.com/v3/refund/domestic/refunds";

    @Autowired
    private WeChatProperties weChatProperties;

    /**
     * 获取调用微信接口的客户端工具对象
     *
     * @return
     */
    private CloseableHttpClient getClient() {
        PrivateKey merchantPrivateKey = null;
        try {
            //merchantPrivateKey商户API私钥，如何加载商户API私钥请看常见问题
            merchantPrivateKey = PemUtil.loadPrivateKey(new FileInputStream(new File(weChatProperties.getPrivateKeyFilePath())));
            //加载平台证书文件
            X509Certificate x509Certificate = PemUtil.loadCertificate(new FileInputStream(new File(weChatProperties.getWeChatPayCertFilePath())));
            //wechatPayCertificates微信支付平台证书列表。你也可以使用后面章节提到的“定时更新平台证书功能”，而不需要关心平台证书的来龙去脉
            List<X509Certificate> wechatPayCertificates = Arrays.asList(x509Certificate);

            WechatPayHttpClientBuilder builder = WechatPayHttpClientBuilder.create()
                    .withMerchant(weChatProperties.getMchid(), weChatProperties.getMchSerialNo(), merchantPrivateKey)
                    .withWechatPay(wechatPayCertificates);

            // 通过WechatPayHttpClientBuilder构造的HttpClient，会自动的处理签名和验签
            CloseableHttpClient httpClient = builder.build();
            return httpClient;
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 发送post方式请求
     *
     * @param url
     * @param body
     * @return
     */
    private String post(String url, String body) throws Exception {
        CloseableHttpClient httpClient = getClient();

        HttpPost httpPost = new HttpPost(url);
        httpPost.addHeader(HttpHeaders.ACCEPT, ContentType.APPLICATION_JSON.toString());
        httpPost.addHeader(HttpHeaders.CONTENT_TYPE, ContentType.APPLICATION_JSON.toString());
        httpPost.addHeader("Wechatpay-Serial", weChatProperties.getMchSerialNo());
        httpPost.setEntity(new StringEntity(body, "UTF-8"));

        CloseableHttpResponse response = httpClient.execute(httpPost);
        try {
            String bodyAsString = EntityUtils.toString(response.getEntity());
            return bodyAsString;
        } finally {
            httpClient.close();
            response.close();
        }
    }

    /**
     * 发送get方式请求
     *
     * @param url
     * @return
     */
    private String get(String url) throws Exception {
        CloseableHttpClient httpClient = getClient();

        HttpGet httpGet = new HttpGet(url);
        httpGet.addHeader(HttpHeaders.ACCEPT, ContentType.APPLICATION_JSON.toString());
        httpGet.addHeader(HttpHeaders.CONTENT_TYPE, ContentType.APPLICATION_JSON.toString());
        httpGet.addHeader("Wechatpay-Serial", weChatProperties.getMchSerialNo());

        CloseableHttpResponse response = httpClient.execute(httpGet);
        try {
            String bodyAsString = EntityUtils.toString(response.getEntity());
            return bodyAsString;
        } finally {
            httpClient.close();
            response.close();
        }
    }

    /**
     * jsapi下单
     *
     * @param orderNum    商户订单号
     * @param total       总金额
     * @param description 商品描述
     * @param openid      微信用户的openid
     * @return
     */
    private String jsapi(String orderNum, BigDecimal total, String description, String openid) throws Exception {
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("appid", weChatProperties.getAppid());
        jsonObject.put("mchid", weChatProperties.getMchid());
        jsonObject.put("description", description);
        jsonObject.put("out_trade_no", orderNum);
        jsonObject.put("notify_url", weChatProperties.getNotifyUrl());

        JSONObject amount = new JSONObject();
        amount.put("total", total.multiply(new BigDecimal(100)).setScale(2, BigDecimal.ROUND_HALF_UP).intValue());
        amount.put("currency", "CNY");

        jsonObject.put("amount", amount);

        JSONObject payer = new JSONObject();
        payer.put("openid", openid);

        jsonObject.put("payer", payer);

        String body = jsonObject.toJSONString();
        return post(JSAPI, body);
    }

    /**
     * 小程序支付
     *
     * @param orderNum    商户订单号
     * @param total       金额，单位 元
     * @param description 商品描述
     * @param openid      微信用户的openid
     * @return
     */
    public JSONObject pay(String orderNum, BigDecimal total, String description, String openid) throws Exception {
        //统一下单，生成预支付交易单
        String bodyAsString = jsapi(orderNum, total, description, openid);
        //解析返回结果
        JSONObject jsonObject = JSON.parseObject(bodyAsString);
        System.out.println(jsonObject);

        String prepayId = jsonObject.getString("prepay_id");
        if (prepayId != null) {
            String timeStamp = String.valueOf(System.currentTimeMillis() / 1000);
            String nonceStr = RandomStringUtils.randomNumeric(32);
            ArrayList<Object> list = new ArrayList<>();
            list.add(weChatProperties.getAppid());
            list.add(timeStamp);
            list.add(nonceStr);
            list.add("prepay_id=" + prepayId);
            //二次签名，调起支付需要重新签名
            StringBuilder stringBuilder = new StringBuilder();
            for (Object o : list) {
                stringBuilder.append(o).append("\n");
            }
            String signMessage = stringBuilder.toString();
            byte[] message = signMessage.getBytes();

            Signature signature = Signature.getInstance("SHA256withRSA");
            signature.initSign(PemUtil.loadPrivateKey(new FileInputStream(new File(weChatProperties.getPrivateKeyFilePath()))));
            signature.update(message);
            String packageSign = Base64.getEncoder().encodeToString(signature.sign());

            //构造数据给微信小程序，用于调起微信支付
            JSONObject jo = new JSONObject();
            jo.put("timeStamp", timeStamp);
            jo.put("nonceStr", nonceStr);
            jo.put("package", "prepay_id=" + prepayId);
            jo.put("signType", "RSA");
            jo.put("paySign", packageSign);

            return jo;
        }
        return jsonObject;
    }

    /**
     * 申请退款
     *
     * @param outTradeNo    商户订单号
     * @param outRefundNo   商户退款单号
     * @param refund        退款金额
     * @param total         原订单金额
     * @return
     */
    public String refund(String outTradeNo, String outRefundNo, BigDecimal refund, BigDecimal total) throws Exception {
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("out_trade_no", outTradeNo);
        jsonObject.put("out_refund_no", outRefundNo);

        JSONObject amount = new JSONObject();
        amount.put("refund", refund.multiply(new BigDecimal(100)).setScale(2, BigDecimal.ROUND_HALF_UP).intValue());
        amount.put("total", total.multiply(new BigDecimal(100)).setScale(2, BigDecimal.ROUND_HALF_UP).intValue());
        amount.put("currency", "CNY");

        jsonObject.put("amount", amount);
        jsonObject.put("notify_url", weChatProperties.getRefundNotifyUrl());

        String body = jsonObject.toJSONString();

        //调用申请退款接口
        return post(REFUNDS, body);
    }
}

实体类

OrderPaymentVO

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class OrderPaymentVO implements Serializable {

    private String nonceStr; //随机字符串
    private String paySign; //签名
    private String timeStamp; //时间戳
    private String signType; //签名算法
    private String packageStr; //统一下单接口返回的 prepay_id 参数值

}

微信支付相关配置

application.yml

sky:
  wechat:
    appid: ****************
    secret: ****************************
    mchid : 1561414111
    mchSerialNo: 4B3B3DC35414AD50B1B755BAF8DE9CC7CF111111
    privateKeyFilePath: D:\apiclient_key.pem
    apiV3Key: CZBK51236435wxpay435434323FF1111
    weChatPayCertFilePath: D:\wechatpay_166D96F876F45C7D07CE98952A96EC9803681111.pem
    notifyUrl: https://www.weixin.qq.com/wxpay/pay.php
    refundNotifyUrl: https://www.weixin.qq.com/wxpay/pay.php

application.yml

sky:
  wechat:
    appid: ${sky.wechat.appid}
    secret: ${sky.wechat.secret}
    mchid : ${sky.wechat.mchid}
    mchSerialNo: ${sky.wechat.mchSerialNo}
    privateKeyFilePath: ${sky.wechat.privateKeyFilePath}
    apiV3Key: ${sky.wechat.apiV3Key}
    weChatPayCertFilePath: ${sky.wechat.weChatPayCertFilePath}
    notifyUrl: ${sky.wechat.notifyUrl}
    refundNotifyUrl: ${sky.wechat.refundNotifyUrl}

配置类

WeChatProperties

@Component
@ConfigurationProperties(prefix = "sky.wechat")
@Data
public class WeChatProperties {

    private String appid; //小程序的appid
    private String secret; //小程序的秘钥
    private String mchid; //商户号
    private String mchSerialNo; //商户API证书的证书序列号
    private String privateKeyFilePath; //商户私钥文件
    private String apiV3Key; //证书解密的密钥
    private String weChatPayCertFilePath; //平台证书
    private String notifyUrl; //支付成功的回调地址
    private String refundNotifyUrl; //退款成功的回调地址
}