【微信支付】【java】Springboot对接开发微信支付

本文章是介绍java对接（微信小程序）微信支付，包括微信预下单、支付、退款等等。 

 一、微信配置申请

1、微信支付配置申请

详细操作流程参考官方文档：https://pay.weixin.qq.***/wiki/doc/apiv3/open/pay/chapter2_8_1.shtml#part-1

配置完成需要以下信息：

• APPID
• 商户号（mchid）
• 商户API私钥（apiclient_key.pem）
• 商户证书序列号
• 商户APIv3密钥

二、开发环境

1、开发环境

开发语言：java ，编译工具：idea ，框架：springboot ，仓库：maven

2、maven依赖

<dependency>
  <groupId>***.github.wechatpay-apiv3</groupId>
  <artifactId>wechatpay-java</artifactId>
  <version>0.2.10</version>
</dependency>

3、application.yml文件配置

#微信支付配置
wx:
  pay:
    #应用id（小程序id）
    appId: wx6b5xxxxxxxxxxxx
    #商户号
    merchantId: 1xxxxxxxxx
    #商户API私钥
    privateKey: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    #商户证书序列号
    merchantSerialNumber: 315DDXXXXXXXXXXXXXXXXXXXXXXXXXXX
    #商户APIv3密钥
    apiV3Key: XXXXXXXXXXXXXXXXXXXXXXXXXX
    #支付通知地址
    payNotifyUrl: https://xxx.xxxx.xxx.xxx/xx/xxxx/xxxx/openapi/wx/payNotify
    #退款通知地址
    refundNotifyUrl: https://xxx.xxx.xxx.xxx/xxxx/xxxx/xxxx/openapi/wx/refundNotify

三、代码开发

1、配置类

import lombok.Data;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.***ponent;

/**
 * @author caozhen
 * @ClassName WxPayConfig
 * @description: 微信支付配置类
 * @date 2024年01月03日
 * @version: 1.0
 */
@Data
@***ponent
@ConfigurationProperties(prefix = "wx.pay")
public class WxPayConfig {
    //APPID
    private String appId;
    //mchid
    private String merchantId;
    //商户API私钥
    private String privateKey;
    //商户证书序列号
    private String merchantSerialNumber;
    //商户APIv3密钥
    private String apiV3Key;
    //支付通知地址
    private String payNotifyUrl;
    //退款通知地址
    private String refundNotifyUrl;
}

2、初始化商户配置

import ***.wechat.pay.java.core.RSAAutoCertificateConfig;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.annotation.Resource;

/**
 * @author caozhen
 * @ClassName WxPayAutoCertificateConfig
 * @description: 微信支付证书自动更新配置
 * @date 2024年01月03日
 * @version: 1.0
 */
@Configuration
public class WxPayAutoCertificateConfig {
    @Resource
    private WxPayConfig wxPayConfig;

    /**
     * 初始化商户配置
     * @return
     */
    @Bean
    public RSAAutoCertificateConfig rsaAutoCertificateConfig() {
        RSAAutoCertificateConfig config = new RSAAutoCertificateConfig.Builder()
                .merchantId(wxPayConfig.getMerchantId())
                .privateKey(wxPayConfig.getPrivateKey())
                .merchantSerialNumber(wxPayConfig.getMerchantSerialNumber())
                .apiV3Key(wxPayConfig.getApiV3Key())
                .build();
        return config;
    }
}

3、JSAPI微信预下单

3.1、先建个WxPayService服务类

import ***.alibaba.fastjson.JSONObject;
import ***.baomidou.mybatisplus.mapper.EntityWrapper;
import ***.baomidou.mybatisplus.mapper.Wrapper;
import ***.hvit.user.exception.DataA***essException;
import ***.hvit.user.util.DateUtils;
import ***.hvit.user.util.R;
import ***.hvit.user.yst.entity.WxOrderEntity;
import ***.hvit.user.yst.entity.WxPayLogEntity;
import ***.hvit.user.yst.request.CreateOrderReq;
import ***.hvit.user.yst.request.QueryOrderReq;
import ***.hvit.user.yst.request.WxNotifyReq;
import ***.hvit.user.yst.service.WKShoppingMallService;
import ***.hvit.user.yst.service.data.WxOrderDataService;
import ***.hvit.user.yst.service.data.WxPayLogDataService;
import ***.wechat.pay.java.core.RSAAutoCertificateConfig;
import ***.wechat.pay.java.core.exception.HttpException;
import ***.wechat.pay.java.core.exception.MalformedMessageException;
import ***.wechat.pay.java.core.exception.ServiceException;
import ***.wechat.pay.java.core.notification.NotificationParser;
import ***.wechat.pay.java.core.notification.RequestParam;
import ***.wechat.pay.java.service.payments.jsapi.*;
import ***.wechat.pay.java.service.payments.jsapi.model.*;
import ***.wechat.pay.java.service.payments.jsapi.model.Amount;
import ***.wechat.pay.java.service.payments.model.Transaction;
import ***.wechat.pay.java.service.refund.RefundService;
import ***.wechat.pay.java.service.refund.model.*;
import io.swagger.annotations.ApiModelProperty;
import io.swagger.models.auth.In;
import lombok.extern.slf4j.Slf4j;
import org.apache.***mons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.annotation.Async;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.Resource;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigDecimal;
import java.util.Date;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 * @author caozhen
 * @ClassName WxPayService
 * @description: 微信支付
 * @date 2024年01月03日
 * @version: 1.0
 */
@Slf4j
@Service
public class WxPayService {

    @Resource
    private WxPayConfig wxPayConfig;
    @Autowired
    private RSAAutoCertificateConfig rsaAutoCertificateConfig;
    @Autowired
    private WxOrderDataService wxOrderDataService;
    @Autowired
    private WxPayLogDataService wxPayLogDataService;

    /***
     * 预支付订单
     * @param req
     * @return
     */
    public R createOrder(CreateOrderReq req) throws Exception {
        if (req == null) {
            return R.error("创建订单失败，缺少参数！");
        }
        //先解密
        
        String orderNo = req.getOutTradeNo();
        Integer totalFee = req.getTotal();
        //创建初始化订单
        //todo,创建订单这边你们自己来（后面我会放出表结构）
        //请求微信支付相关配置
        JsapiServiceExtension service =
                new JsapiServiceExtension.Builder()
                        .config(rsaAutoCertificateConfig)
                        .signType("RSA") // 不填默认为RSA
                        .build();
        PrepayWithRequestPaymentResponse response = new PrepayWithRequestPaymentResponse();
        try {
            PrepayRequest request = new PrepayRequest();
            request.setAppid(wxPayConfig.getAppId());
            request.setMchid(wxPayConfig.getMerchantId());
            request.setDescription(description);
            request.setOutTradeNo(orderNo);
            request.setNotifyUrl(wxPayConfig.getPayNotifyUrl());
            Amount amount = new Amount();
            //amount.setTotal(totalFee.multiply(new BigDecimal("100")).intValue());
            amount.setTotal(totalFee);
            request.setAmount(amount);
            Payer payer = new Payer();
            payer.setOpenid(req.getWxOpenId());
            request.setPayer(payer);
            log.info("请求预支付下单，请求参数：{}", JSONObject.toJSONString(request));
            // 调用预下单接口
            response = service.prepayWithRequestPayment(request);
            log.info("订单【{}】发起预支付成功，返回信息：{}", orderNo, response);
        } catch (HttpException e) { // 发送HTTP请求失败
            log.error("微信下单发送HTTP请求失败，错误信息：{}", e.getHttpRequest());
            return R.error("下单失败");
        } catch (ServiceException e) { // 服务返回状态小于200或大于等于300，例如500
            log.error("微信下单服务状态错误，错误信息：{}", e.getErrorMessage());
            return R.error("下单失败");
        } catch (MalformedMessageException e) { // 服务返回成功，返回体类型不合法，或者解析返回体失败
            log.error("服务返回成功，返回体类型不合法，或者解析返回体失败，错误信息：{}", e.getMessage());
            return R.error("下单失败");
        }

        return R.ok().put("data", response);
    }
}

3.1、R实体类

import java.util.HashMap;
import java.util.Map;

/**
 *
 * @author 曹震
 * @date 2024-1-03
 */
public class R extends HashMap<String, Object> {

    private static final long serialVersionUID = 1L;

    public R() {
        put("code", 0);
    }

    public R(Integer code) {
        put("code", code);
        put("data", new HashMap<String, Object>());
    }

    public R(Integer code, String msg) {
        put("code", code);
        put("msg", msg);
        put("data", new HashMap<String, Object>());
    }

    public static R error() {
        return error(500, "未知异常，请联系管理员");
    }

    public static R errorDebug(String message) {
        return error(500, "未知异常 " + message + "，请联系管理员");
    }

    public static R error(String msg) {
        return error(500, msg);
    }
   

    public static R error(int code, String msg) {
        R r = new R();
        r.put("code", code);
        r.put("msg", msg);
        return r;
    }

    public R errorInfo(String msg) {
        this.put("errorMsg", msg);
        return this;
    }

    public static R ok(String msg) {
        R r = new R();
        r.put("msg", msg);
        r.put("data", new HashMap<String, Object>());
        return r;
    }

    public static R ok(Map<String, Object> map) {
        R r = new R();
        r.putAll(map);
        r.put("data", new HashMap<String, Object>());
        return r;
    }

    public static R ok() {
        return new R().put("msg", "su***ess").put("data", new HashMap<String, Object>());
    }

    public static R ok(Integer size) {
        return new R().put("data", new HashMap<String, Object>((int)Math.round(size / 0.75)));
    }

    @Override
    public R put(String key, Object value) {
        super.put(key, value);
        return this;
    }

    /**
     * 添加返回结果数据
     *
     * @param key
     * @param value
     * @return
     */
    public R putData(String key, Object value) {
        Map<String, Object> map = (HashMap<String, Object>)this.get("data");
        map.put(key, value);
        return this;
    }


}

3.2、CreateOrderReq类

import io.swagger.annotations.ApiModelProperty;
import lombok.Data;


/**
 * @author caozhen
 * @ClassName CreateOrderReq
 * @description: TODO
 * @date 2024年01月03日
 * @version: 1.0
 */
@Data
public class CreateOrderReq {

    @ApiModelProperty(name = "description", value = "商品描述")
    private String description;

    @ApiModelProperty(name = "wxOpenId", value = "用户小程序openid")
    private String wxOpenId;

    @ApiModelProperty(name = "outTradeNo", value = "商户订单号")
    private String outTradeNo;

    @ApiModelProperty(name = "totalFee", value = "支付金额，单位：分")
    private Long totalFee;

4、微信支付回调通知 

/***
     * 微信支付回调通知
     * @param request
     * @return
     * @throws IOException
     */
    @Transactional
    public synchronized String payNotify(HttpServletRequest request) throws Exception {
        log.info("------收到支付通知------");
        // 请求头Wechatpay-Signature
        String signature = request.getHeader("Wechatpay-Signature");
        // 请求头Wechatpay-nonce
        String nonce = request.getHeader("Wechatpay-Nonce");
        // 请求头Wechatpay-Timestamp
        String timestamp = request.getHeader("Wechatpay-Timestamp");
        // 微信支付证书序列号
        String serial = request.getHeader("Wechatpay-Serial");
        // 签名方式
        String signType = request.getHeader("Wechatpay-Signature-Type");
        // 构造 RequestParam
        RequestParam requestParam = new RequestParam.Builder()
                .serialNumber(serial)
                .nonce(nonce)
                .signature(signature)
                .timestamp(timestamp)
                .signType(signType)
                .body(HttpServletUtils.getRequestBody(request))
                .build();

        // 初始化 NotificationParser
        NotificationParser parser = new NotificationParser(rsaAutoCertificateConfig);
        // 以支付通知回调为例，验签、解密并转换成 Transaction
        log.info("验签参数：{}", requestParam);
        Transaction transaction = parser.parse(requestParam, Transaction.class);
        log.info("验签成功！-支付回调结果：{}", transaction.toString());

        Map<String, String> returnMap = new HashMap<>(2);
        returnMap.put("code", "FAIL");
        returnMap.put("message", "失败");
        //修改订单前，建议主动请求微信查询订单是否支付成功，防止恶意post
        Wrapper wrapper = new EntityWrapper<WxOrderEntity>();
        wrapper.eq("out_trade_no", transaction.getOutTradeNo());
        //wrapper.eq("transaction_id", transaction.getTransactionId());
        WxOrderEntity wxOrderEntity = wxOrderDataService.selectOne(wrapper);
        if (wxOrderEntity != null) {
            if (wxOrderEntity.getPayStatus() == 1) {
                //此时已经是支付成功，不在处理订单信息
                returnMap.put("code", "SU***ESS");
                returnMap.put("message", "成功");
                return JSONObject.toJSONString(returnMap);
            }
        }
        if (Transaction.TradeStateEnum.SU***ESS != transaction.getTradeState()) {
            log.info("内部订单号【{}】,微信支付订单号【{}】支付未成功", transaction.getOutTradeNo(), transaction.getTransactionId());
            if (wxOrderEntity != null) {
                wxOrderEntity.setUpdateTime(new Date());
                wxOrderEntity.setPayStatus(2);
                wxOrderEntity.setPayNonce(nonce);
                wxOrderEntity.setTransactionId(transaction.getTransactionId());
                //修改订单信息
                wxOrderDataService.updateById(wxOrderEntity);
            }
            return JSONObject.toJSONString(returnMap);
        }
        if (wxOrderEntity != null) {
            wxOrderEntity.setUpdateTime(new Date());
            wxOrderEntity.setPayTime(DateUtils.stringToDateTime(transaction.getSu***essTime()));
            wxOrderEntity.setPayDate(DateUtils.stringToDateTime(transaction.getSu***essTime()));
            wxOrderEntity.setPayStatus(1);
            wxOrderEntity.setPayNonce(nonce);
            wxOrderEntity.setTransactionId(transaction.getTransactionId());
            //修改订单信息
            wxOrderDataService.updateById(wxOrderEntity);
            //同时处理支付记录
            Wrapper payWrapper = new EntityWrapper<WxPayLogEntity>();
            wrapper.eq("out_trade_no", transaction.getOutTradeNo());
            wrapper.eq("pay_status", 1);//支付
            WxPayLogEntity wxPayLogEntity = wxPayLogDataService.selectOne(payWrapper);
            if (wxPayLogEntity == null) {
                wxPayLogEntity = new WxPayLogEntity();
                wxPayLogEntity.setCreateTime(new Date());
                wxPayLogEntity.setOutTradeNo(wxOrderEntity.getOutTradeNo());
                wxPayLogEntity.setPayStatus(1);
                wxPayLogEntity.setTotalFee(wxOrderEntity.getTotalFee());
                wxPayLogEntity.setTransactionId(wxOrderEntity.getTransactionId());
                wxPayLogEntity.setWxOpenId(wxOrderEntity.getWxOpenId());
                wxPayLogDataService.insert(wxPayLogEntity);
            }
        }
  
        returnMap.put("code", "SU***ESS");
        returnMap.put("message", "成功");
        return JSONObject.toJSONString(returnMap);
    }

5、根据商户订单号查询订单（out_trade_no）

/***
     * 根据商户订单号查询订单 outTradeNo
     * @param req
     * @return
     */
    @Transactional
    public R queryOrderByOrderNo(QueryOrderReq req) {
        QueryOrderByOutTradeNoRequest queryRequest = new QueryOrderByOutTradeNoRequest();
        queryRequest.setMchid(wxPayConfig.getMerchantId());
        queryRequest.setOutTradeNo(req.getOrderNo());
        try {
            JsapiServiceExtension service =
                    new JsapiServiceExtension.Builder()
                            .config(rsaAutoCertificateConfig)
                            .signType("RSA") // 不填默认为RSA
                            .build();
            Transaction result = service.queryOrderByOutTradeNo(queryRequest);
            LinkedHashMap retmap = new LinkedHashMap();
            //支付成功
            if (Transaction.TradeStateEnum.SU***ESS == result.getTradeState()) {
                log.info("内部订单号【{}】,微信支付订单号【{}】支付成功", result.getOutTradeNo(), result.getTransactionId());
                retmap.put("out_trade_no", result.getOutTradeNo());
                retmap.put("transaction_id", result.getTransactionId());
                retmap.put("su***ess", true);
                retmap.put("msg", "支付成功！");
                retmap.put("su***ess_time", DateUtils.getDateTimeString(DateUtils.stringToDateTime(result.getSu***essTime())));
                //主动查询
                Wrapper wrapper = new EntityWrapper<WxOrderEntity>();
                wrapper.eq("out_trade_no", req.getOrderNo());
                WxOrderEntity wxOrderEntity = wxOrderDataService.selectOne(wrapper);
                if (wxOrderEntity != null) {
                    if (wxOrderEntity.getPayStatus() != 1) {
                        wxOrderEntity.setPayStatus(1);
                        wxOrderEntity.setTransactionId(result.getTransactionId());
                        wxOrderEntity.setPayDate(DateUtils.stringToDateTime(result.getSu***essTime()));
                        wxOrderEntity.setPayTime(DateUtils.stringToDateTime(result.getSu***essTime()));
                        wxOrderEntity.setUpdateTime(new Date());
                        wxOrderDataService.updateById(wxOrderEntity);
                        //同时处理支付记录
                        Wrapper payWrapper = new EntityWrapper<WxPayLogEntity>();
                        wrapper.eq("out_trade_no", req.getOrderNo());
                        WxPayLogEntity wxPayLogEntity = wxPayLogDataService.selectOne(payWrapper);
                        if (wxPayLogEntity == null) {
                            wxPayLogEntity = new WxPayLogEntity();
                            wxPayLogEntity.setCreateTime(new Date());
                            wxPayLogEntity.setOutTradeNo(wxOrderEntity.getOutTradeNo());
                            wxPayLogEntity.setPayStatus(1);
                            wxPayLogEntity.setTotalFee(wxOrderEntity.getTotalFee());
                            wxPayLogEntity.setTransactionId(result.getTransactionId());
                            wxPayLogEntity.setWxOpenId(wxOrderEntity.getWxOpenId());
                            wxPayLogDataService.insert(wxPayLogEntity);
                        }
                    }
                }
            } else {
                log.info("内部订单号【{}】,微信支付订单号【{}】支付未成功", result.getOutTradeNo(), result.getTransactionId());
                retmap.put("out_trade_no", result.getOutTradeNo());
                retmap.put("transaction_id", result.getTransactionId());
                retmap.put("su***ess", false);
                retmap.put("msg", "支付失败！");
                retmap.put("su***ess_time", null);
            }
            return R.ok().put("data", retmap);
        } catch (ServiceException e) {
            log.error("订单查询失败，返回码：{},返回信息：{}", e.getErrorCode(), e.getErrorMessage());
            return R.error("订单查询失败！");
        }
    }

5.1  QueryOrderReq类

mport io.swagger.annotations.ApiModelProperty;
import lombok.Data;

/**
 * @author caozhen
 * @ClassName QueryOrderReq
 * @description: 支付查询
 * @date 2024年01月04日
 * @version: 1.0
 */
@Data
public class QueryOrderReq {
    @ApiModelProperty(name = "paymentNo", value = "微信支付订单号，同：transaction_id")
    private String paymentNo;

    @ApiModelProperty(name = "orderNo", value = "商户订单号,同：out_trade_no")
    private String orderNo;
}

6、根据支付订单号查询订单 （transaction_id）

/***
     * 根据支付订单号查询订单 paymentNo
     * @param req
     * @return
     */
    @Transactional
    public R queryOrderByPaymentNo(QueryOrderReq req) {
        QueryOrderByIdRequest queryRequest = new QueryOrderByIdRequest();
        queryRequest.setMchid(wxPayConfig.getMerchantId());
        queryRequest.setTransactionId(req.getPaymentNo());
        try {
            JsapiServiceExtension service =
                    new JsapiServiceExtension.Builder()
                            .config(rsaAutoCertificateConfig)
                            .signType("RSA") // 不填默认为RSA
                            .build();
            Transaction result = service.queryOrderById(queryRequest);
            LinkedHashMap map = new LinkedHashMap();
            //支付成功
            if (Transaction.TradeStateEnum.SU***ESS == result.getTradeState()) {
                log.info("内部订单号【{}】,微信支付订单号【{}】支付成功", result.getOutTradeNo(), result.getTransactionId());
                map.put("out_trade_no", result.getOutTradeNo());
                map.put("transaction_id", result.getTransactionId());
                map.put("su***ess", true);
                map.put("msg", "支付成功！");
                map.put("su***ess_time", DateUtils.getDateTimeString(DateUtils.stringToDateTime(result.getSu***essTime())));
                //主动查询
                Wrapper wrapper = new EntityWrapper<WxOrderEntity>();
                wrapper.eq("transaction_id", req.getPaymentNo());
                WxOrderEntity wxOrderEntity = wxOrderDataService.selectOne(wrapper);
                if (wxOrderEntity != null) {
                    if (wxOrderEntity.getPayStatus() != 1) {
                        wxOrderEntity.setPayStatus(1);
                        wxOrderEntity.setPayDate(DateUtils.stringToDateTime(result.getSu***essTime()));
                        wxOrderEntity.setPayTime(DateUtils.stringToDateTime(result.getSu***essTime()));
                        wxOrderEntity.setUpdateTime(new Date());
                        wxOrderDataService.updateById(wxOrderEntity);
                        //同时处理支付记录
                        Wrapper payWrapper = new EntityWrapper<WxPayLogEntity>();
                        wrapper.eq("transaction_id", req.getPaymentNo());
                        WxPayLogEntity wxPayLogEntity = wxPayLogDataService.selectOne(payWrapper);
                        if (wxPayLogEntity == null) {
                            wxPayLogEntity = new WxPayLogEntity();
                            wxPayLogEntity.setCreateTime(new Date());
                            wxPayLogEntity.setOutTradeNo(wxOrderEntity.getOutTradeNo());
                            wxPayLogEntity.setPayStatus(1);
                            wxPayLogEntity.setTotalFee(wxOrderEntity.getTotalFee());
                            wxPayLogEntity.setTransactionId(result.getTransactionId());
                            wxPayLogEntity.setWxOpenId(wxOrderEntity.getWxOpenId());
                            wxPayLogDataService.insert(wxPayLogEntity);
                        }
                    }
                }
            } else {
                log.info("内部订单号【{}】,微信支付订单号【{}】支付未成功", result.getOutTradeNo(), result.getTransactionId());
                map.put("out_trade_no", result.getOutTradeNo());
                map.put("transaction_id", result.getTransactionId());
                map.put("su***ess", false);
                map.put("msg", "支付失败！");
                map.put("su***ess_time", null);
            }
            return R.ok().put("data", map);
        } catch (ServiceException e) {
            log.error("订单查询失败，返回码：{},返回信息：{}", e.getErrorCode(), e.getErrorMessage());
            return R.error("订单查询失败！");
        }
    }

7、微信申请退款

/***
     * 微信申请退款
     * @param outTradeNo 商户订单号
     * @param totalAmount
     * @return
     */
    public R createRefund(String outTradeNo, Long totalAmount) {
        //返回参数
        LinkedHashMap map = new LinkedHashMap();
        map.put("out_trade_no", outTradeNo);
        map.put("su***ess", false);
        map.put("msg", "正在申请退款中！");
        String outRefundNo = "REFUND_" + outTradeNo;
        map.put("out_refund_no", outRefundNo);
        //申请退款订单，需要变更订单记录
        Wrapper wrapper = new EntityWrapper<WxOrderEntity>();
        wrapper.eq("out_trade_no", outTradeNo);
        WxOrderEntity wxOrderEntity = wxOrderDataService.selectOne(wrapper);
        if (wxOrderEntity == null) {
            return R.error("订单不存在，申请退款不存在！");
        }
        wxOrderEntity.setPayStatus(4);//退款中
        wxOrderEntity.setUpdateTime(new Date());
        wxOrderDataService.updateById(wxOrderEntity);
        try {
            // 构建退款service
            RefundService service = new RefundService.Builder()
                    .config(rsaAutoCertificateConfig)
                    .build();
            CreateRequest request = new CreateRequest();
            // 调用request.setXxx(val)设置所需参数，具体参数可见Request定义
            request.setOutTradeNo(outTradeNo);
            request.setOutRefundNo(outRefundNo);

            AmountReq amount = new AmountReq();
            amount.setTotal(totalAmount);
            amount.setRefund(totalAmount);
            amount.setCurrency("***Y");

            request.setAmount(amount);
            request.setNotifyUrl(wxPayConfig.getRefundNotifyUrl());

            //接收退款返回参数
            Refund refund = service.create(request);
            log.info("退款返回信息：{}", refund);
            if (refund.getStatus().equals(Status.SU***ESS)) {
                map.put("su***ess", true);
                map.put("msg", "退款成功！");
                //说明退款成功，开始接下来的业务操作
                //主动查询
                Wrapper againWrapper = new EntityWrapper<WxOrderEntity>();
                againWrapper.eq("out_trade_no", outTradeNo);
                WxOrderEntity orderEntity = wxOrderDataService.selectOne(againWrapper);
                if (orderEntity != null) {
                    orderEntity.setPayStatus(3);//退款成功
                    orderEntity.setUpdateTime(new Date());
                    wxOrderDataService.updateById(orderEntity);
                    //同时处理退款记录
                    Wrapper payWrapper = new EntityWrapper<WxPayLogEntity>();
                    payWrapper.eq("out_trade_no", outTradeNo);
                    payWrapper.eq("pay_status", 2);//退款
                    WxPayLogEntity wxPayLogEntity = wxPayLogDataService.selectOne(payWrapper);
                    if (wxPayLogEntity == null) {
                        wxPayLogEntity = new WxPayLogEntity();
                        wxPayLogEntity.setCreateTime(new Date());
                        wxPayLogEntity.setOutTradeNo(outTradeNo);
                        wxPayLogEntity.setPayStatus(2);
                        wxPayLogEntity.setTotalFee(totalAmount.intValue());
                        wxPayLogEntity.setTransactionId(wxOrderEntity.getTransactionId());
                        wxPayLogEntity.setOutRefundNo(outRefundNo);
                        wxPayLogEntity.setWxOpenId(wxOrderEntity.getWxOpenId());
                        wxPayLogDataService.insert(wxPayLogEntity);
                    }
                }
            }
        } catch (ServiceException e) {
            log.error("退款失败！，错误信息：{}", e.getMessage());
            return R.error("退款失败！");
        } catch (Exception e) {
            log.error("服务返回成功，返回体类型不合法，或者解析返回体失败，错误信息：{}", e.getMessage());
            return R.error("退款失败！");
        }
        return R.ok().put("data", map);
    }

8、退款回调通知 

待续......有需要的再联系我！

四、mysql表结构

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for t_wx_order
-- ----------------------------
DROP TABLE IF EXISTS `t_wx_order`;
CREATE TABLE `t_wx_order`  (
  `uuid` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL,
  `trade_name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '商品名称',
  `description` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '订单描述',
  `out_trade_no` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '(商户)订单流水号',
  `transaction_id` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '微信订单号',
  `total_fee` int(10) NULL DEFAULT NULL ***MENT '订单金额(单位：分)',
  `pay_nonce` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '支付成功后的随机32位字符串',
  `pay_time` datetime NULL DEFAULT NULL ***MENT '支付时间',
  `pay_date` date NULL DEFAULT NULL ***MENT '支付日期',
  `pay_status` int(3) NULL DEFAULT 0 ***MENT '0:待支付，1：支付成功，2：支付失败，3：退款成功，4：正在退款中，5：未知',
  `wx_open_id` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '微信小程序openid',
  `status` int(2) NULL DEFAULT 0 ***MENT '0：未删除，1：已删除',
  `create_time` datetime NULL DEFAULT NULL ***MENT '创建订单时间',
  `update_time` datetime NULL DEFAULT NULL ***MENT '修改订单时间',
  PRIMARY KEY (`uuid`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_bin ***MENT = '微信商品订单表' ROW_FORMAT = Dynamic;

-- ----------------------------
-- Table structure for t_wx_pay_log
-- ----------------------------
DROP TABLE IF EXISTS `t_wx_pay_log`;
CREATE TABLE `t_wx_pay_log`  (
  `uuid` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL,
  `wx_open_id` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '微信用户openid',
  `out_trade_no` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '(商户)订单流水号',
  `out_refund_no` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '(商户)退款流水号',
  `transaction_id` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NULL DEFAULT NULL ***MENT '微信订单号',
  `total_fee` int(10) NULL DEFAULT NULL ***MENT '支付金额',
  `pay_status` int(2) NULL DEFAULT NULL ***MENT '1：支付，2：退款',
  `create_time` datetime NULL DEFAULT NULL ***MENT '创建时间',
  PRIMARY KEY (`uuid`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_bin ***MENT = '微信用户支付记录表' ROW_FORMAT = Dynamic;

SET FOREIGN_KEY_CHECKS = 1;

五、controller类

退款回调通知，和controller就不写了，如果需要，联系我即可！

哎呀呀呀，缺少了一个类，代码如下：

import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
/**
 * @author caozhen
 * @ClassName HttpServletUtils
 * @description: TODO
 * @date 2024年01月04日
 * @version: 1.0
 */
public class HttpServletUtils {
    /**
     * 获取请求体
     *
     * @param request
     * @return
     * @throws IOException
     */
    public static String getRequestBody(HttpServletRequest request) throws IOException {
        ServletInputStream stream = null;
        BufferedReader reader = null;
        StringBuffer sb = new StringBuffer();
        try {
            stream = request.getInputStream();
            // 获取响应
            reader = new BufferedReader(new InputStreamReader(stream));
            String line;
            while ((line = reader.readLine()) != null) {
                sb.append(line);
            }
        } catch (IOException e) {
            throw new IOException("读取返回支付接口数据流出现异常！");
        } finally {
            reader.close();
        }
        return sb.toString();
    }
}

如果你在微信支付回调通知中出现 “签名错误”，并且你是windows服务器，请在HttpServletUtils 类中，将reader = new BufferedReader(new InputStreamReader(stream));   替换成：reader = new BufferedReader(new InputStreamReader(stream,"UTF-8"));

替换完整代码：

import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
/**
 * @author caozhen
 * @ClassName HttpServletUtils
 * @description: TODO
 * @date 2024年01月04日
 * @version: 1.0
 */
public class HttpServletUtils {
    /**
     * 获取请求体
     *
     * @param request
     * @return
     * @throws IOException
     */
    public static String getRequestBody(HttpServletRequest request) throws IOException {
        ServletInputStream stream = null;
        BufferedReader reader = null;
        StringBuffer sb = new StringBuffer();
        try {
            stream = request.getInputStream();
            // 获取响应
            reader = new BufferedReader(new InputStreamReader(stream,"UTF-8"));
            String line;
            while ((line = reader.readLine()) != null) {
                sb.append(line);
            }
        } catch (IOException e) {
            throw new IOException("读取返回支付接口数据流出现异常！");
        } finally {
            reader.close();
        }
        return sb.toString();
    }
}