Java二维码生成与解码

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基于google zxing 的Java二维码生成与解码

一、添加Maven依赖（解码时需要上传二维码图片，所以需要依赖文件上传包）

<!-- google二维码工具 -->
<dependency>
 <groupId>com.google.zxing</groupId>
 <artifactId>javase</artifactId>
 <version>3.1.0</version>
</dependency>

<!-- 文件上传 -->
<dependency>
 <groupId>commons-fileupload</groupId>
 <artifactId>commons-fileupload</artifactId>
 <version>1.3.1</version>
</dependency>
<dependency>
 <groupId>commons-io</groupId>
 <artifactId>commons-io</artifactId>
 <version>2.4</version>
</dependency>

二、创建生成二维码接口（接口参数为二维码内容，通常是URL）

/**
 * 生成二维码
 * google zxing 实现
 * @param text
 * @return
 */
@RequestMapping(value = "/qrcode/encode", method = RequestMethod.POST)
public void encodeQrCode(String text, HttpServletResponse response) {
   try {
      // 设置二维码参数
      Map<EncodeHintType, Object> hints = new HashMap<EncodeHintType, Object>();
      hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
      BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, 150, 150, hints);
      //返回二维码
      MatrixToImageWriter.writeToStream(bitMatrix, "jpg", response.getOutputStream());
   } catch (Exception e) {
      e.printStackTrace();
   }
}

三、创建二维码解码接口（直接返回解码后的二维码内容）

/**
 * 二维码图片解码
 * google zxing 实现
 * @param qrImg
 * @return
 */
@RequestMapping(value = "/qrcode/decode", method = RequestMethod.POST)
public String decodeQrCode(MultipartFile qrImg) {
   if (!qrImg.isEmpty()) {
      try {
         BufferedImage image = ImageIO.read(qrImg.getInputStream());

         BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(new BufferedImageLuminanceSource(image)));

         // 定义二维码的参数:
         HashMap<DecodeHintType, Object> hints = new HashMap<>();
         // 定义字符集
         hints.put(DecodeHintType.CHARACTER_SET, "utf-8");

         Result result = new MultiFormatReader().decode(binaryBitmap, hints);

         return result.getText();
      } catch (Exception e) {
         e.printStackTrace();
      }
   }

   return null;
}