Notes with attachment not working

[arams]

I use below code for uploading a note with attachments. But I received following error in response.

errorcode 400 - {"description":"Validation failed","errors":[{"field":"body","message":"It should be a/an String","code":"missing_field"}]}

If i comment out following line, able to upload body alone.

meb.addBinaryBody("attachments[]", attach2,
ContentType.TEXT_PLAIN.withCharset("utf-8"), attach2.getName());

`
public static String getArrayForUrlPostv2(String urlString) {

    try {

        final HttpClientBuilder hcBuilder = HttpClientBuilder.create();
        final RequestBuilder reqBuilder = RequestBuilder.post();
        final RequestConfig.Builder rcBuilder = RequestConfig.custom();

        // URL object from API endpoint:
        URL url = new URL(urlString);
        final String urlHost = url.getHost();
        final int urlPort = url.getPort();
        final String urlProtocol = url.getProtocol();
        reqBuilder.setUri(url.toURI());

        // Authentication:
        List<String> authPrefs = new ArrayList<>();
        authPrefs.add(AuthSchemes.BASIC);
        rcBuilder.setTargetPreferredAuthSchemes(authPrefs);
        CredentialsProvider credsProvider = new BasicCredentialsProvider();
        credsProvider.setCredentials(
                new AuthScope(urlHost, urlPort, AuthScope.ANY_REALM),
                new UsernamePasswordCredentials(PreferenceMgr.getString(PreferenceMgr.KEY_AGENT_EMAIL),
                                                PreferenceMgr.getString(PreferenceMgr.KEY_AGENT_PASSWORD)));
        hcBuilder.setDefaultCredentialsProvider(credsProvider);
        AuthCache authCache = new BasicAuthCache();
        AuthSchemeBase authScheme = new BasicScheme();
        authCache.put(new HttpHost(urlHost, urlPort, urlProtocol), authScheme);
        HttpClientContext hccContext = HttpClientContext.create();
        hccContext.setAuthCache(authCache);

        // Body:
        MultipartEntityBuilder meb = MultipartEntityBuilder.create();
        meb.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);


        File attach2 = ApplicationNekt.getContext().getFileStreamPath(Constants.LogFileName + ".txt");
        meb.addBinaryBody("attachments[]", attach2,
                ContentType.TEXT_PLAIN.withCharset("utf-8"), attach2.getName());

        //meb.addTextBody("body", "testing");
        meb.addTextBody("body", "test", ContentType.TEXT_PLAIN);
        meb.addTextBody("private", "true", ContentType.TEXT_PLAIN);


        reqBuilder.setEntity(meb.build());

        // Execute:
        RequestConfig rc = rcBuilder.build();
        reqBuilder.setConfig(rc);

        HttpClient hc = hcBuilder.build();
        HttpUriRequest req = reqBuilder.build();
        HttpResponse response = hc.execute(req, hccContext);


        // Print out:
        HttpEntity body = response.getEntity();
        InputStream is = body.getContent();
        BufferedReader br = new BufferedReader(new InputStreamReader(is, Charset.forName("utf-8")));
        String line;
        StringBuilder sb = new StringBuilder();
        while ((line = br.readLine()) != null) {
            sb.append(line);
        }
        int response_status = response.getStatusLine().getStatusCode();
        String response_body = sb.toString();

        Utilities.writeToLogFile(Constants.LOG_ERROR_LEVEL, "Response Status: " + response_status);
        Utilities.writeToLogFile(Constants.LOG_ERROR_LEVEL, "Body:\n");
        Utilities.writeToLogFile(Constants.LOG_ERROR_LEVEL, response_body);
        if (response_status > 400) {
            Utilities.writeToLogFile(Constants.LOG_ERROR_LEVEL, "X-Request-Id: " + response.getFirstHeader("x-request-id").getValue());
        } else if (response_status == 201) {
            //For creation response_status is 201 where are as for other actions it is 200
            try {
                Utilities.writeToLogFile(Constants.LOG_ERROR_LEVEL, "Update Successfull");
                //Creating JSONObject for the response string
                JSONObject response_json = new JSONObject(sb.toString());
                Utilities.writeToLogFile(Constants.LOG_ERROR_LEVEL, "Ticket ID: " + response_json.get("id"));
                return "success";
                //Utilities.writeToLogFile(Constants.LOG_ERROR_LEVEL, "Location : " + response.getFirstHeader("location").getValue());
            } catch (JSONException e) {
                Utilities.writeToLogFile(Constants.LOG_ERROR_LEVEL, "Error in JSON Parsing\n :" + e);
            }
        }

    } catch (Exception e) {
        e.printStackTrace();
    }
    return null;

`