java 微信支付前后端代码（小程序+java)

微信小程序支付--业务流程：
1.小程序发起订单，支付
2.后端程序封装数据调用微信接口发起预支付，微信返回预支付数据到小程序
3.小程序弹出支付界面输入密码确认支付，调用微信支付接口支付
4.微信支付成功调用后端外网的回调接口，回调接口接收到微信数据，解析读取数据后调用微信接口通知微信已收到回调
5.更新系统表的订单状态已支付
6.小程序端1秒刷新一次调用后端接口，查看订单状态是否支付成功，支付成功显示支付成功。

1.下订单及支付接口
package com.sky.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.github.pagehelper.Page;
import com.github.pagehelper.PageHelper;
import com.sky.constant.MessageConstant;
import com.sky.context.BaseContext;
import com.sky.dto.;
import com.sky.entity.;
import com.sky.exception.AddressBookBusinessException;
import com.sky.exception.OrderBusinessException;
import com.sky.exception.ShoppingCartBusinessException;
import com.sky.mapper.*;
import com.sky.result.PageResult;
import com.sky.service.OrderService;
import com.sky.utils.WeChatPayUtil;
import com.sky.vo.OrderPaymentVO;
import com.sky.vo.OrderStatisticsVO;
import com.sky.vo.OrderSubmitVO;
import com.sky.vo.OrderVO;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;
import java.math.BigDecimal;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**

订单
*/
@Service
@Slf4j
public class OrderServiceImpl implements OrderService {
@Autowired
private OrderMapper orderMapper;
@Autowired
private OrderDetailMapper orderDetailMapper;
@Autowired
private ShoppingCartMapper shoppingCartMapper;
@Autowired
private UserMapper userMapper;
@Autowired
private AddressBookMapper addressBookMapper;
@Autowired
private WeChatPayUtil weChatPayUtil;

/**
- 用户下单
- @param ordersSubmitDTO
- @return
  */
  @Transactional
  public OrderSubmitVO submitOrder(OrdersSubmitDTO ordersSubmitDTO) {
  //异常情况的处理（收货地址为空、购物车为空）
  AddressBook addressBook = addressBookMapper.getById(ordersSubmitDTO.getAddressBookId());
  if (addressBook == null) {
  throw new AddressBookBusinessException(MessageConstant.ADDRESS_BOOK_IS_NULL);
  }
  
  Long userId = BaseContext.getCurrentId();
  ShoppingCart shoppingCart = new ShoppingCart();
  shoppingCart.setUserId(userId);
  
  //查询当前用户的购物车数据
  List shoppingCartList = shoppingCartMapper.list(shoppingCart);
  if (shoppingCartList == null || shoppingCartList.size() == 0) {
  throw new ShoppingCartBusinessException(MessageConstant.SHOPPING_CART_IS_NULL);
  }
  
  //构造订单数据
  Orders order = new Orders();
  BeanUtils.copyProperties(ordersSubmitDTO,order);
  order.setPhone(addressBook.getPhone());
  order.setAddress(addressBook.getDetail());
  order.setConsignee(addressBook.getConsignee());
  order.setNumber(String.valueOf(System.currentTimeMillis()));
  order.setUserId(userId);
  order.setStatus(Orders.PENDING_PAYMENT);
  order.setPayStatus(Orders.UN_PAID);
  order.setOrderTime(LocalDateTime.now());
  
  //向订单表插入1条数据
  orderMapper.insert(order);
  
  //订单明细数据
  List orderDetailList = new ArrayList<>();
  for (ShoppingCart cart : shoppingCartList) {
  OrderDetail orderDetail = new OrderDetail();
  BeanUtils.copyProperties(cart, orderDetail);
  orderDetail.setOrderId(order.getId());
  orderDetailList.add(orderDetail);
  }
  
  //向明细表插入n条数据
  orderDetailMapper.insertBatch(orderDetailList);
  
  //清理购物车中的数据
  shoppingCartMapper.deleteByUserId(userId);
  
  //封装返回结果
  OrderSubmitVO orderSubmitVO = OrderSubmitVO.builder()
  .id(order.getId())
  .orderNumber(order.getNumber())
  .orderAmount(order.getAmount())
  .orderTime(order.getOrderTime())
  .build();
  
  return orderSubmitVO;
  }
/**
- 订单支付
- @param ordersPaymentDTO
- @return
  */
  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
  */
  public void paySuccess(String outTradeNo) {
  
  // 根据订单号查询订单
  Orders ordersDB = orderMapper.getByNumber(outTradeNo);
  
  // 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);
  }

}

2.回调相关方法：
package com.sky.controller.notify;

import com.alibaba.druid.support.json.JSONUtils;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.sky.properties.WeChatProperties;
import com.sky.service.OrderService;
import com.wechat.pay.contrib.apache.httpclient.util.AesUtil;
import lombok.extern.slf4j.Slf4j;
import org.apache.http.entity.ContentType;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.BufferedReader;
import java.nio.charset.StandardCharsets;
import java.util.HashMap;

/**

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);
  }
/**
- 回调后读取数据
- @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;
  }
/**
- 收到回调后给微信响应
- @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();
  }
  }

3.微信支付工具类

package com.sky.utils;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.sky.properties.WeChatProperties;
import com.wechat.pay.contrib.apache.httpclient.WechatPayHttpClientBuilder;
import com.wechat.pay.contrib.apache.httpclient.util.PemUtil;
import org.apache.commons.lang.RandomStringUtils;
import org.apache.http.HttpHeaders;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.util.EntityUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.math.BigDecimal;
import java.security.PrivateKey;
import java.security.Signature;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Base64;
import java.util.List;

/**

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 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
  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);
    }
    }

posted @ 2024-02-15 10:45 大树2 阅读(400) 评论(0) 编辑收藏举报

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