java下载内网图片给前端

@PostMapping("/view")
public ApiResponse view(@RequestBody JSONObject json, HttpServletRequest request,HttpServletResponse response) throws Exception {
    String userId = getUserId(request);
    if (StringUtils.isEmpty(userId)) {
        return ResponseCode.response(ResponseCode.token_error);
    }

    //获取到上传的文件数据
    Object imgUrlObj = json.get("imgUrl");
    if (imgUrlObj == null) {
        return new ApiResponse(ResponseCode.parameter_error.getCode(), "imgUrl不能为空");
    }

    String url = imgUrlObj.toString();
    BufferedImage img = FileUtil.getBufferedImage(url);
    if (img == null) {
        throw new GAPOIException(GapoiResponseCode.URL_IS_NOT_IMG);
    }

    String format = url.substring(url.lastIndexOf(".") + 1);
    ImageIO.write(img, format, response.getOutputStream());

    return null;
}

/**
 * httpurl图片路径 返回BufferedImage
 * @param url
 * @return
 * @throws Exception
 */
public static BufferedImage getBufferedImage(String url) throws Exception{
   URL readUrl = new URL(url);
   URLConnection urlConnection = readUrl.openConnection();
   urlConnection.setConnectTimeout(1000);
   urlConnection.setReadTimeout(5000);
   urlConnection.connect();
   InputStream inputStream = urlConnection.getInputStream();
   return ImageIO.read(inputStream);
}