<!-- google二維碼工具 -->
<dependency>
 <groupId>com.google.zxing</groupId>
 <artifactId>javase</artifactId>
 <version>3.1.0</version>
</dependency>

<!-- 文件上傳 -->
<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、創建生成二維碼接口（接口參數為二維碼內容，通常是URL）

/**
 * 生成二維碼
 * google zxing 實現
 * @param text
 * @return
 */
@RequestMapping(value = "/qrcode/encode", method = RequestMethod.POST)
public void encodeQrCode(String text, HttpServletResponse response) {
   try {
      // 設置二維碼參數
      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);
      //返回二維碼
      MatrixToImageWriter.writeToStream(bitMatrix, "jpg", response.getOutputStream());
   } catch (Exception e) {
      e.printStackTrace();
   }
}

三、創建二維碼解碼接口（直接返回解碼後的二維碼內容）

/**
 * 二維碼圖片解碼
 * google zxing 實現
 * @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)));

         // 定義二維碼的參數:
         HashMap<DecodeHintType, Object> hints = new HashMap<>();
         // 定義字符集
         hints.put(DecodeHintType.CHARACTER_SET, "utf-8");

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

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

   return null;
}

Java二維碼生成與解碼