springboot 保存文件

@ResponseBody
@RequestMapping(value = "/img-upload", method = RequestMethod.POST)
private Map<String, Object> imgUpload(@RequestParam("files") MultipartFile[] files, HttpServletRequest request) throws Exception {

    // 获得物理路径webapp所在路径
    String pathRoot = request.getSession().getServletContext().getRealPath("");
    pathRoot = request.getSession().getServletContext().getRealPath("resources/upload/images/");

    File fileDir = new File(pathRoot);
    if (!fileDir.exists()) {
        // 递归生成文件夹
        fileDir.mkdirs();
    }
    String path = "";
    List<String> imgs = new ArrayList<>();
    if (files != null && files.length > 0) {

        for (int i = 0; i < files.length; i++) {
            MultipartFile file = files[i];

            // 生成uuid作为文件名称
            String uuid = UUID.randomUUID().toString().replaceAll("-", "");
            // 获得文件类型（可以判断如果不是图片，禁止上传）
            String contentType = file.getContentType();
            // 获得文件后缀名称
            String imageName = contentType.substring(contentType.indexOf("/") + 1);
            path = uuid + "." + imageName;
            file.transferTo(new File(pathRoot + path));
            
            
            // 获取当前项目的完整url
            String requestURL = request.getRequestURL().toString();
            // 获取当前项目的请求路径uri
            String requestURI = request.getRequestURI();
            // 得到去掉了uri的路径
            String url = requestURL.substring(0, requestURL.length()-requestURI.length() + 1);
            // 返回
            // return url + newFileName;
            imgs.add(url+ "upload/images/" + path);
        }
        
    }

    Map<String, Object> result = new HashMap<>();
    result.put("errno", 0);
    result.put("data", imgs);

    return result;
}