Java 微信当面付生成二维码支付实现

1. maven依赖

        <!-- 微信支付sdk --><dependency><groupId>com.github.wxpay</groupId><artifactId>wxpay-sdk</artifactId><version>0.0.3</version></dependency><!-- 二维码工具 --><dependency><groupId>com.google.zxing</groupId><artifactId>core</artifactId><version>3.3.3</version></dependency><dependency><groupId>com.google.zxing</groupId><artifactId>javase</artifactId><version>3.3.3</version></dependency>

2. 准备工作

a. WxPayConfig 配置类

在第一篇关于微信支付文章里有写到：
Java 微信支付统一下单、支付回调、订单查询实现
这里直接用了

b. 二维码图片本地存储位置

file.qrCode是在配置文件里写到的二维码图片本地存储位置，

c. 配置虚拟路径

需要在项目里配置虚拟路径，
参考SpringBoot文件虚拟路径配置，
以及图片开放访问，有权限限制的项目需要这一步，项目不同开放的方式也不同，举例：

如果是分布式项目的话，集成MinIO来存储图片会更好，参考
Java MinIO文件上传返回访问路径及访问配置

3. 代码

a. QrCodeUtil

(同支付宝二维码支付)

import com.google.zxing.*;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.util.Hashtable;public class QrCodeUtil {/*** 生成包含字符串信息的二维码图片* @param outputStream 文件输出流路径* @param content 二维码携带信息*/public static boolean createQrCode(OutputStream outputStream, String content) throws WriterException, IOException{//设置二维码纠错级别ＭＡＰHashtable<EncodeHintType, ErrorCorrectionLevel> hintMap = new Hashtable<EncodeHintType, ErrorCorrectionLevel>();hintMap.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);  // 矫错级别QRCodeWriter qrCodeWriter = new QRCodeWriter();//创建比特矩阵(位矩阵)的QR码编码的字符串BitMatrix byteMatrix = qrCodeWriter.encode(content, BarcodeFormat.QR_CODE, 900, 900, hintMap);// 使BufferedImage勾画QRCode  (matrixWidth 是行二维码像素点)int matrixWidth = byteMatrix.getWidth();BufferedImage image = new BufferedImage(matrixWidth-200, matrixWidth-200, BufferedImage.TYPE_INT_RGB);image.createGraphics();Graphics2D graphics = (Graphics2D) image.getGraphics();graphics.setColor(Color.WHITE);graphics.fillRect(0, 0, matrixWidth, matrixWidth);// 使用比特矩阵画并保存图像graphics.setColor(Color.BLACK);for (int i = 0; i < matrixWidth; i++){for (int j = 0; j < matrixWidth; j++){if (byteMatrix.get(i, j)){graphics.fillRect(i-100, j-100, 1, 1);}}}return ImageIO.write(image, "JPEG", outputStream);}
}

b. controller

@Value("${file.qrCode}")private String qrCode;@PreAuthorize("@el.check('anonymous')")@PostMapping("/wxpayPrecreate")public ResponseEntity wxPrecreate(HttpServletRequest request, @RequestBody Map params) throws Exception {// 保存未支付订单ShopOrderDTO shopOrderDTO = createOrder(params, 0);// 处理请求参数WxPayConfig wxPayConfig = new WxPayConfig(shopDeviceService);WXPay wxPay = new WXPay(wxPayConfig);Map<String,String> data = new HashMap<>();data.put("out_trade_no", shopOrderDTO.getId()+"");   //订单编号data.put("total_fee",shopOrderDTO.getAmount().toString());   //金额(单位为分) intdata.put("spbill_create_ip", IPUtil.getIPAddress(request));data.put("nonce_str", WXPayUtil.generateNonceStr());   // 随机字符串小于32位data.put("mch_id",wxPayConfig.getMchID());data.put("appid",wxPayConfig.getAppID());// 这里二维码支付是区别于手机网站支付的地方data.put("trade_type","NATIVE");	data.put("product_id", shopOrderDTO.getId().toString());data.put("device_info",wxPayConfig.getDeviceInfo());data.put("notify_url",wxPayConfig.getNotifyUrl());data.put("fee_type",wxPayConfig.getFeeType());data.put("body",wxPayConfig.getBody());data.put("scene_info", wxPayConfig.getSceneInfo());// 生成签名String s = WXPayUtil.generateSignature(data, wxPayConfig.getKey());data.put("sign",s);// 发起下单请求logger.info("发起 WxPay 下单请求");Map<String, String> respData = wxPay.unifiedOrder(data);// 处理下单结果if ("SUCCESS".equals(respData.get("return_code"))){if ("SUCCESS".equals(respData.get("result_code"))) {String path = qrCode + shopOrderDTO.getId() + "WXPay.jpg";String httpPath = "/qrCode/" + shopOrderDTO.getId() + "WXPay.jpg";File file = new File(path);if (!file.getParentFile().exists()) {file.getParentFile().mkdirs();}QrCodeUtil.createQrCode(new FileOutputStream(file), respData.get("code_url"));respData.put("qrcode", httpPath);respData.put("out_trade_no", shopOrderDTO.getId()+"");shopLogService.anonymousCreate(shopLogService.getShopLog(shopOrderDTO.getStoreId(), shopOrderDTO.getDeviceId(), "生成WxPay订单","订单编号 : " + shopOrderDTO.getId()));return new ResponseEntity<>(respData, HttpStatus.OK);} else {shopLogService.anonymousCreate(shopLogService.getShopLog(shopOrderDTO.getStoreId(), shopOrderDTO.getDeviceId(), "WxPay下单失败","err_code_des : " + respData.get("err_code_des")));throw new Exception(respData.get("err_code_des"));}} else {shopLogService.anonymousCreate(shopLogService.getShopLog(shopOrderDTO.getStoreId(), shopOrderDTO.getDeviceId(), "WxPay下单失败","return_msg : " + respData.get("err_code_des")));throw new Exception(respData.get("return_msg"));}}