Use Okhttp to implement upload file + parameter request interface form-data

    /**
      * Writing comments is a good habit
      *
      * @param mFile
      * @param accountIndex
      * @param exportType
      * @param clear
      * @param email
      * @param dimensions
      * @return
      * @throws IOException
      */
    public String upload(MultipartFile mFile, Integer accountIndex, String exportType,
                         Boolean clear, String email, String dimensions) throws IOException {
        // This is the process of converting MultipartFile to File        File file = new File((()));
        ((), file);
        // URL interface path        String url = "http://localhost:8080/upload";
        // file is the file to be uploaded File() Here I upload excel, and other types can change this parse by yourself        RequestBody fileBody = (("application/"), file);//This is the file written in, and there is also a path, but I am writing the file file here. If parse does not work, you can directly change the "multipart/form-data"        // Create an OkHttpClient instance and set the timeout time        OkHttpClient okHttpClient = new ()
                .connectTimeout(60L, )
                .writeTimeout(60L, )
                .readTimeout(60L, )
                .build();
        // Not only can it support file transmission, but it can also pass parameters while passing files.        MultipartBody requestBody = new ()
                .setType() // Set the parameter transfer to form-data format                .addFormDataPart("account_index", (accountIndex))
                .addFormDataPart("export_type", exportType)
                .addFormDataPart("clear", (clear))
                .addFormDataPart("email", email)
                .addFormDataPart("dimensions", dimensions)
                .addFormDataPart("file", (), fileBody) // The intermediate parameter is the file name                .build();

        // Build a request request body, and if you need to pass the request header, add it yourself        Request request = new ()
                .url(url)
                .post(requestBody)
                .build();
        Response response = null;
        String result = "";
        try {
            // Send a request            response = (request).execute();
            result = ().string();
            (url + "Send request result:" + result);
            if (!()) {
                ("Request failed");
                return "Request failed";
            }
            ().close();
        } catch (IOException e) {
            (());
        }
        // Temporary files will be generated locally and need to be deleted after use        if (()) {
            ();
        }
        return result;
    }

(@RequestPart("file") MultipartFile file,
@RequestParam("accountIndex") Integer accountIndex,
@RequestParam("exportType") String exportType,
@RequestParam(value = "clear", required = false) Boolean clear,
@RequestParam("email") String email,
@RequestParam(value = "dimensions", required = false) String dimensions)

(@RequestPart("file") MultipartFile file, RequestVo req)