I / O错误：类路径资源[]无法解析为URL，因为它不存在；

Question

  

org.springframework.web.client.ResourceAccessException：I / O错误：类路径资源[storage / emulated / 0 / DCIM / Camera / IMG_20190130_135103614.jpg]无法解析为URL，因为它不存在；嵌套的异常是java.io.FileNotFoundException：类路径资源[storage / emulated / 0 / DCIM / Camera / IMG_20190130_135103614.jpg]无法解析为URL，因为它不存在。

尝试从图库上载图像时出现此错误。 同一代码的工作，当图像被从绘制文件夹上传。

@Override
    protected void onPreExecute() {
        showLoadingProgressDialog();

        Resource resource = new ClassPathResource(file.getPath());

        formData = new LinkedMultiValueMap<String, Object>(); "jpg");
        formData.add("description", "image");
        formData.add("file", resource);
    }
    @Override
    protected String doInBackground(Void... params) {
        try {
            // The URL for making the POST request
            final String url = getString(R.string.base_uri) + "/***";

            HttpHeaders requestHeaders = new HttpHeaders();

            // Sending multipart/form-data
            requestHeaders.setContentType(MediaType.MULTIPART_FORM_DATA);

            // Populate the MultiValueMap being serialized and headers in an HttpEntity object to use for the request
            HttpEntity<MultiValueMap<String, Object>> requestEntity = new HttpEntity<MultiValueMap<String, Object>>(
                    formData, requestHeaders);

            // Create a new RestTemplate instance
            RestTemplate restTemplate = new RestTemplate(true);

            // Make the network request, posting the message, expecting a String in response from the server
            ResponseEntity<String> response = restTemplate.exchange(url, HttpMethod.POST, requestEntity,
                    String.class);

            // Return the response body to display to the user
            return response.getBody();
        } catch (Exception e) {
            Log.e(TAG, e.getMessage(), e);
        }

        return null;
    }

服务器端代码是

     @RequestMapping(value = "/*", method = RequestMethod.POST, headers = 
     "Content-Type=multipart/form-data")
     public @ResponseBody String 
    handleFormUpload(@RequestParam("description") String description,
        @RequestParam("file") MultipartFile file) {

    if (!file.isEmpty()) {
        byte[] bytes = null;
        try {
            bytes = file.getBytes();
        } catch (IOException e) {
            System.out.println("error processing uploaded file");
        }
        return "file upload received! Name:[" + description + "] Size:["
                + bytes.length + "]";
    } else {
        return "file upload failed!";
    }
}