private void fileUploadWithThumbnail(String attach_file_seq, String file_path, String user_id, String thumbnail) {
    File uploadFile = new File(file_path);
    MultipartEntityBuilder builder = MultipartEntityBuilder.create() //객체 생성
            .setCharset(Charset.forName("UTF-8")) //인코딩을 UTF-8로
            .setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
    builder.addPart("file", new FileBody(uploadFile)); //빌더에 FileBody 객체에 인자로 File 객체를 넣어준다.
    builder.addTextBody("attach_file_seq", attach_file_seq, ContentType.create("Multipart/related", "UTF-8"));
    builder.addTextBody("user_id", user_id, ContentType.create("Multipart/related", "UTF-8"));
    builder.addTextBody("thumbnail", thumbnail, ContentType.create("Multipart/related", "UTF-8"));

    try {
        InputStream inputStream = null;
        HttpClient httpClient = new DefaultHttpClient();
        HttpPost post = new HttpPost(server_domain + "/file/fileUploadDisk.json"); //전송할 URL
        HttpEntity multipart = builder.build();
        post.setEntity(multipart);
        HttpResponse httpResponse = httpClient.execute(post);
        HttpEntity httpEntity = httpResponse.getEntity();
    } catch (Exception e) {
        e.printStackTrace();
    }
}