使用Java实现二维码生成与扫码验证功能

<dependency>
    <groupId>com.google.zxing</groupId>
    <artifactId>javase</artifactId>
    <version>3.3.3</version>
</dependency>

public static BufferedImage createImage(String charSet, String content, int qrWidth, int qrHeight) {
    Hashtable<EncodeHintType, Object> hints = new Hashtable<>();
    hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H); // 设置容错级别
    hints.put(EncodeHintType.CHARACTER_SET, charSet); // 设置字符集
    hints.put(EncodeHintType.MARGIN, 1); // 设置二维码边距
 
    BitMatrix bitMatrix;
    try {
        bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, qrWidth, qrHeight, hints);
    } catch (WriterException e) {
        throw new RuntimeException("生成二维码失败", e);
    }
 
    int width = bitMatrix.getWidth();
    int height = bitMatrix.getHeight();
    BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
 
    for (int x = 0; x < width; x++) {
        for (int y = 0; y < height; y++) {
            image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);
        }
    }
 
    return image;
}

private void generateQrCode(Long reservationId) {
    // 生成签名
    String sign = CreateSignUtil.createSign(vehicleProperties.getCodeUrl(), reservationId);
    System.err.println("生成的签名 = " + sign);
 
    // 构建完整的 URL
    String url = vehicleProperties.getCodeUrl() + reservationId;
    System.err.println("生成的URL: " + url);
 
    // 生成二维码
    BufferedImage bufferedImage = QrCodeUtil.createImage("utf-8", url, 300, 300);
 
    // 上传二维码
    try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) {
        ImageIO.write(bufferedImage, "jpg", outputStream);
        InputStream inputStream = new ByteArrayInputStream(outputStream.toByteArray());
        minioService.uploadFile(CustomConstant.BUCKET_NAME_QRCODE, inputStream, "image/jpg", reservationId, CustomConstant.NUM_100_LONG, "QrCode.jpg", CustomConstant.FILE_TYPE_QRCODE);
    } catch (IOException e) {
        e.printStackTrace();
    }
}

public static String createSign(String secretKey, Long subId) {
    String text = secretKey + subId + secretKey;
    try {
        MessageDigest md = MessageDigest.getInstance("MD5");
        byte[] digest = md.digest(text.getBytes(StandardCharsets.UTF_8));
        StringBuilder sb = new StringBuilder();
        for (byte b : digest) {
            sb.append(String.format("%02x", b & 0xff));
        }
        return sb.toString();
    } catch (NoSuchAlgorithmException e) {
        throw new RuntimeException("MD5 算法不可用", e);
    }
}

@GetMapping("/qrcode")
public ResultApi<?> handleQrCode(@RequestParam Long reservationId, @RequestParam String clientSign) {
    // 重新计算签名
    String serverSign = CreateSignUtil.createSign(vehicleProperties.getCodeUrl(), reservationId);
 
    // 比较签名
    if (serverSign.equals(clientSign)) {
        GroundReservationVO.ReservationDetail byId = groundReservationService.getById(reservationId);
        return ResultApi.success("查询成功", byId);
    } else {
        return ResultApi.success("验证失败！参数不匹配。");
    }
}