Как работать с API Яндекс переводчика через Json на Java Android

String key = "CggVAgAAA...dnQ=";
        key = "trnsl.1.1.2017031...d35ed564f787";
        String baseUrl = "https://translate.yandex.net/api/v1.5/tr/translate";
        String finalUrl = baseUrl + "?lang=" + lang + "&key=" + key; //"ru-en"
        try {
            URL url = new URL(finalUrl);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setDoOutput(true);
            connection.setRequestMethod("POST");
            connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            connection.setRequestProperty("Content-Length", out.length + "");
            connection.setRequestProperty("Accept", "*/*");
            OutputStream outstr = connection.getOutputStream();
            outstr.write(out);
            connection.connect();
            if (connection.getResponseCode() == 200) {
                JsonObject jobj = new JsonParser().parse(
                        new InputStreamReader(connection.getInputStream())).getAsJsonObject();
                JsonArray jarr = jobj.get("text").getAsJsonArray();
                return jarr.get(0).getAsString();
            } else {
                return "Error. Site response non 200";
            }
 
        } catch (IOException e) {
            e.printStackTrace();
            return "Error";
        }

URL url = new URL("https://translate.api.cloud.yandex.net/translate/v2/translate");
            urlConnection = (HttpURLConnection) url.openConnection();
            urlConnection.setRequestProperty("targetLanguageCode", "ru");
            urlConnection.setRequestProperty("sourceLanguageCode", "en");
            urlConnection.setRequestProperty("format", "PLAIN_TEXT");
            urlConnection.setRequestProperty("texts", "[\"Hello dog\"]");
            urlConnection.setRequestProperty("folderId", "b1ghs...3b9bv");
            urlConnection.setRequestProperty("Content-Type", "application/json");
            urlConnection.setRequestProperty("Authorization", "Bearer ${AQVNzcuC...bIE7pKh}");
            urlConnection.setRequestMethod("POST");
            urlConnection.setDoInput(true);
            urlConnection.setDoOutput(true);
            urlConnection.connect();
 
            JSONObject jo = new JSONObject();
            jo.put("folder_id", "b1gh...3b9bv");
            jo.put("texts", "[\"Hello dog\"]");
            jo.put("targetLanguageCode", "ru");
 
            bos = new BufferedOutputStream(urlConnection.getOutputStream());
            bos.write(jo.toString().getBytes());
 
//            InputStream response = urlConnection.getInputStream();
 
            String result = urlConnection.getResponseMessage();
            Log.d("", "server response: " + result); //проверить, что вернет сервер
            return result;

   Gson gson = new Gson();
            JSONObject jo = new JSONObject();
            JSONArray ar = new JSONArray();
            String w = this.text;
            ar.put(w);
 
            jo.put("sourceLanguageCode", this.langFrom);
            jo.put("targetLanguageCode", this.langTo);
            jo.put("languageCode", this.langFrom);
            jo.put("texts", ar);
            String joString = jo.toString();
 
            URL url = new URL("https://translate.api.cloud.yandex.net/translate/v2/translate");
 
            urlConnection = (HttpURLConnection) url.openConnection();
            urlConnection.setRequestProperty("Content-Type", "application/json");
            urlConnection.setRequestProperty("Authorization", "Api-Key "+ this.key);
            urlConnection.setRequestMethod("POST");
            urlConnection.setDoInput(true);
            urlConnection.setDoOutput(true);
 
            urlConnection.setRequestProperty("file", jo.toString());
            urlConnection.connect();
 
            DataOutputStream dataOutputStream = new DataOutputStream(urlConnection.getOutputStream());
            dataOutputStream.write(joString.getBytes()); // .writeBytes(joString) - этот вариант путает кодировку
            dataOutputStream.flush();
            dataOutputStream.close();
 
            // при неудачном соединении - выход
            if (!urlConnection.getResponseMessage().equals("OK")) {return result;}
 
            InputStream inputStream = urlConnection.getInputStream();
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
 
            StringBuffer stringBuffer = new StringBuffer();
 
            String inputLine;
            while ((inputLine = bufferedReader.readLine()) != null) {
                stringBuffer.append(inputLine);
            }
            bufferedReader.close();
            JSONObject JOb = new JSONObject(stringBuffer.toString());