Spring for Android, file upload / download

I am starting to use Spring framework in my android project to upload / download file from server. My problem is how to update progress on upload / download? Does anyone have any idea?

My code for uploading a file using Spring:

public String editPersonalAvatar(UserProfile user, String url) {
        String result = "";
        File file = new File(user.getAvatar());
        MultiValueMap<String, Object> mapWithFile;
        mapWithFile = new LinkedMultiValueMap<String, Object>();
        mapWithFile.add("file", new FileSystemResource(file));
        RestTemplate restTemplate = new RestTemplateHelper().createRestTemplate(new FormHttpMessageConverter(),
                                                                   new StringHttpMessageConverter());
        result = restTemplate.postForObject(url, mapWithFile, String.class);

        return result;
    }

      

        
        
        
      

    

Another problem: I am requesting an HTTPPOST to the server and I am getting large JSON (example 2MB). Can I calculate the download percentage?

Sample code:

public static String confirmGetFile(String url, String username,String id) throws Exception {

        MultiValueMap<String, String> map = new LinkedMultiValueMap<String, String>();
                map.add("user", username);

        map.add("id", id);
        RestTemplate restTemplate = new RestTemplateHelper().createRestTemplate(new FormHttpMessageConverter(),
                                                                                new StringHttpMessageConverter());
        String result = restTemplate.postForObject(url, map, String.class);
        Log.d("***RESULT CONFIRM", result);
        return result;
    }