<dependency>
           <groupId>com.alipay.sdk</groupId>
           <artifactId>alipay-sdk-java</artifactId>
           <version>4.22.110.ALL</version>
       </dependency>
       <dependency>
           <groupId>cn.hutool</groupId>
           <artifactId>hutool-all</artifactId>
           <version>5.7.20</version>
       </dependency>

alipay:
appId: 9021000142654289
appPrivateKey: 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
alipayPublicKey: MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAialzjLbre28XpAcAlAhbq3dKvK02gnuHqK1uKXtqh/RuJgoO1rZ8gcw5fUD0qgBba4kWO6y/6or8Xsie1OLc5b2AiBK9LTbn3LRSaCwSPPoQOXq1fDOfbWeD8bFDlNDLLTV+LVRnwMuBJE0vPJGU1jCWy5G0YoIvoGaQcSHlFMq0bD3QBf7qi/OSXwbfpu40jKclvnaSOnn1ylHVFJhHgyzZNOHwaDvAk0F6RwIwakQdRQqfMLeoeQKHIUQcQvKtQkXohbY8AUb1lKWllYy6ge5AKlCMq9diMeftCDLvsubq4Aug1/hhgcyK5El3ERaFnADgUKCqyd3sHPp4IL+x8QIDAQAB
notifyUrl: http://qmqvmt.natappfree.cc/alipay/notify
returnUrl: http://localhost:8888/return

import lombok.Data;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;
@Data
@Component
@ConfigurationProperties(prefix = "alipay") //读取 配置值
public class AliPayConfig {
   private String appId; // appID
   private String appPrivateKey; // 应用私钥
   private String alipayPublicKey; // 支付宝公钥
   private String notifyUrl; // 支付成功后支付宝异步通知的接口地址
   private String returnUrl; // 支付成功之后返回的路径
  
   public String getReturnUrl() {
       return returnUrl;
  }
   public void setReturnUrl(String returnUrl) {
       this.returnUrl = returnUrl;
  }
   public String getAppId() {
       return appId;
  }
   public void setAppId(String appId) {
       this.appId = appId;
  }
   public String getAppPrivateKey() {
       return appPrivateKey;
  }
   public void setAppPrivateKey(String appPrivateKey) {
       this.appPrivateKey = appPrivateKey;
  }
   public String getAlipayPublicKey() {
       return alipayPublicKey;
  }
   public void setAlipayPublicKey(String alipayPublicKey) {
       this.alipayPublicKey = alipayPublicKey;
  }
   public String getNotifyUrl() {
       return notifyUrl;
  }
   public void setNotifyUrl(String notifyUrl) {
       this.notifyUrl = notifyUrl;
  }
}

import lombok.Data;
@Data
public class AliPay {
   private String traceNo; // 我们自己生成的订单编号
   private double totalAmount;// 订单的总金额
   private String subject; // 支付的名称
   private String alipayTraceNo;
   public String getTraceNo() {
       return traceNo;
  }
   public void setTraceNo(String traceNo) {
       this.traceNo = traceNo;
  }
   public double getTotalAmount() {
       return totalAmount;
  }
   public void setTotalAmount(double totalAmount) {
       this.totalAmount = totalAmount;
  }
   public String getSubject() {
       return subject;
  }
   public void setSubject(String subject) {
       this.subject = subject;
  }
   public String getAlipayTraceNo() {
       return alipayTraceNo;
  }
   public void setAlipayTraceNo(String alipayTraceNo) {
       this.alipayTraceNo = alipayTraceNo;
  }
}

package com.kyh.controller;
import cn.hutool.json.JSONObject;
import com.alipay.api.AlipayApiException;
import com.alipay.api.AlipayClient;
import com.alipay.api.DefaultAlipayClient;
import com.alipay.api.internal.util.AlipaySignature;
import com.alipay.api.request.AlipayTradePagePayRequest;
import com.kyh.common.AliPayConfig;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
//import javax.annotation.Resource; //jdk17不能用
//import javax.servlet.http.HttpServletRequest; //jdk17不能用
//import javax.servlet.http.HttpServletResponse; //jdk17不能用
import jakarta.annotation.Resource; // 17用 jakarta
import jakarta.servlet.http.HttpServletRequest; //用jakarta
import jakarta.servlet.http.HttpServletResponse;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
// xjlugv6874@sandbox.com
// 9428521.24 - 30 = 9428491.24 + 30 = 9428521.24
@RestController
@RequestMapping("/alipay")
public class AliPayController {
   private static final String GATEWAY_URL = "https://openapi-sandbox.dl.alipaydev.com/gateway.do"; //   支付宝网关地址，需要改成自己的网关，每个人不一样
   private static final String FORMAT = "JSON"; //   返回格式
   private static final String CHARSET = "UTF-8"; // 编码
   //签名方式
   private static final String SIGN_TYPE = "RSA2"; // 签名方式 密钥
   @Resource
   private AliPayConfig aliPayConfig;
   @GetMapping("/pay") // &subject=xxx&traceNo=xxx&totalAmount=xxx
   public void pay(AliPay aliPay, HttpServletResponse httpResponse) throws Exception {
        // alipay 接受传来的数据
       System.out.println(aliPayConfig.getAppId()+" "+ aliPayConfig.getAppPrivateKey());
       System.out.println(aliPayConfig.getAlipayPublicKey());
       // 测试输出
       
       // 1. 创建Client，通用SDK提供的Client，负责调用支付宝的API
       AlipayClient alipayClient = new DefaultAlipayClient(GATEWAY_URL, aliPayConfig.getAppId(),
               aliPayConfig.getAppPrivateKey(), FORMAT, CHARSET, aliPayConfig.getAlipayPublicKey(), SIGN_TYPE);
       // 2. 创建 Request并设置Request参数
       AlipayTradePagePayRequest request = new AlipayTradePagePayRequest();  // 发送请求的 Request类
       request.setNotifyUrl(aliPayConfig.getNotifyUrl()); // 支付成功后支付宝异步通知的接口地址
       request.setReturnUrl(aliPayConfig.getReturnUrl()); // 支付成功后跳转的页面 AliPayController.java的pay接口设置回调的url：request.setReturnUrl(aliPayConfig.getReturnUrl());
       JSONObject bizContent = new JSONObject();
       System.out.println(aliPay.getSubject()+" "+aliPay.getTraceNo()+" "+aliPay.getTotalAmount());
       bizContent.set("out_trade_no", aliPay.getTraceNo());  // 我们自己生成的订单编号
       bizContent.set("total_amount", aliPay.getTotalAmount()); // 订单的总金额
       bizContent.set("subject", aliPay.getSubject());   // 支付的名称
       bizContent.set("product_code", "FAST_INSTANT_TRADE_PAY");  // 固定配置
       request.setBizContent(bizContent.toString());
       // 执行请求，拿到响应的结果，返回给浏览器
       String form = "";
       try {
           form = alipayClient.pageExecute(request).getBody(); // 调用SDK生成表单
      } catch (AlipayApiException e) {
           e.printStackTrace();
      }
       System.out.println("form="+form);
       httpResponse.setContentType("text/html;charset=" + CHARSET);
       httpResponse.getWriter().write(form);// 直接将完整的表单html输出到页面
       httpResponse.getWriter().flush();
       httpResponse.getWriter().close();
  }
   @PostMapping("/notify")  // 注意这里必须是POST接口
   public String payNotify(HttpServletRequest request) throws Exception {
       System.out.println("支付宝发出异步");
       if (request.getParameter("trade_status").equals("TRADE_SUCCESS")) {
           System.out.println("=========支付宝异步回调========");
           Map<String, String> params = new HashMap<>();
           Map<String, String[]> requestParams = request.getParameterMap();
           for (String name : requestParams.keySet()) {
               params.put(name, request.getParameter(name));
               // System.out.println(name + " = " + request.getParameter(name));
          }
           String outTradeNo = params.get("out_trade_no");
           String gmtPayment = params.get("gmt_payment");
           String alipayTradeNo = params.get("trade_no");
           String sign = params.get("sign");
           String content = AlipaySignature.getSignCheckContentV1(params);
           boolean checkSignature = AlipaySignature.rsa256CheckContent(content, sign, aliPayConfig.getAlipayPublicKey(), "UTF-8"); // 验证签名
           // 支付宝验签
           if (checkSignature) {
               // 验签通过
               System.out.println("交易名称: " + params.get("subject"));
               System.out.println("交易状态: " + params.get("trade_status"));
               System.out.println("支付宝交易凭证号: " + params.get("trade_no"));
               System.out.println("商户订单号: " + params.get("out_trade_no"));
               System.out.println("交易金额: " + params.get("total_amount"));
               System.out.println("买家在支付宝唯一id: " + params.get("buyer_id"));
               System.out.println("买家付款时间: " + params.get("gmt_payment"));
               System.out.println("买家付款金额: " + params.get("buyer_pay_amount"));
               // 查询订单
//               update 表 修改DAO的数据
          }
      }
       return "success";
  }
}