Change the HttpParams code to httpurlconnection

Dude the httpURLConnection for me works fine. Look at my class that has the get and the post:

public class HttpConnections {
 //método get
public static String get(String urlString){
    HttpURLConnection urlConnection = null;
    BufferedReader reader = null;
    String resposta = null;
    try {
        URL url = new URL(urlString);
        urlConnection = (HttpURLConnection) url.openConnection();
        urlConnection.connect();

        InputStream in = new BufferedInputStream(urlConnection.getInputStream());

        reader = new BufferedReader(new InputStreamReader(in));
        String line = "";
        StringBuffer buffer = new StringBuffer();
        while ((line = reader.readLine()) != null){
            buffer.append(line);
        }
        resposta = buffer.toString();
    }catch (Exception e){
        e.printStackTrace();
    }finally {
        if (urlConnection != null){
            urlConnection.disconnect();
        }
        try {
            reader.close();
        }catch (Exception e){
            e.printStackTrace();
        }
    }
    return resposta;
}
//post
public static String  performPostCall(String requestURL,HashMap<String, String> postDataParams) {
    URL url;
    String response = "";
    try {
        url = new URL(requestURL);

        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setReadTimeout(15000);
        conn.setConnectTimeout(15000);
        conn.setRequestMethod("POST");
        conn.setDoInput(true);
        conn.setDoOutput(true);


        OutputStream os = conn.getOutputStream();
        BufferedWriter writer = new BufferedWriter(
                new OutputStreamWriter(os, "UTF-8"));
        writer.write(getPostDataString(postDataParams));

        writer.flush();
        writer.close();
        os.close();
        int responseCode=conn.getResponseCode();

        if (responseCode == HttpsURLConnection.HTTP_OK) {
            String line;
            BufferedReader br=new BufferedReader(new InputStreamReader(conn.getInputStream()));
            while ((line=br.readLine()) != null) {
                response+=line;
            }
        }
        else {
            response="";

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

    return response;
}
private static String getPostDataString(HashMap<String, String> params) throws UnsupportedEncodingException{
    StringBuilder result = new StringBuilder();
    boolean first = true;
    for(Map.Entry<String, String> entry : params.entrySet()){
        if (first)
            first = false;
        else
            result.append("&");

        result.append(URLEncoder.encode(entry.getKey(), "UTF-8"));
        result.append("=");
        result.append(URLEncoder.encode(entry.getValue(), "UTF-8"));
    }

    return result.toString();
} 
}

Then just call:

HttpConnections.get("sua url");//get

The post:

HashMap<String,String> login = new HashMap<>();
login.put("username","nome");
login.put("password","senha");
HttpConnections.performPostCall("sua url",login);

The two methods return a String with the answer. Example in your code:

private class AsyncDataClass extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
    //aqui fica quase da mesma forma

    HashMap<String,String> login = new HashMap<>();
    login.put("username",params[1]);
    login.put("password",params[2]);//passe quantos campos você quizer

    String resposta = HttpConnections.performPostCall(params[0],login);//já retorna uma String, então seu código de converter para String é desnecessário       
    return resposta;
}
@Override
protected void onPreExecute() {
    super.onPreExecute();
}
@Override
protected void onPostExecute(String result) {
    super.onPostExecute(result);
    System.out.println("Resulted Value: " + result);
    if(result.equals("") || result == null){
        Toast.makeText(MainActivity.this, "Server connection failed", Toast.LENGTH_LONG).show();
        return;
    }
    int jsonResult = returnParsedJsonObject(result);
    if(jsonResult == 0){
        Toast.makeText(MainActivity.this, "Invalid username or password", Toast.LENGTH_LONG).show();
        return;
    }
    if(jsonResult == 1){
        Intent intent = new Intent(MainActivity.this, LoginActivity.class);
        intent.putExtra("USERNAME", enteredUsername);
        intent.putExtra("MESSAGE", "You have been successfully login");
        startActivity(intent);
    }
}    
private int returnParsedJsonObject(String result){
    JSONObject resultObject = null;
    int returnedResult = 0;
    try {
        resultObject = new JSONObject(result);
        returnedResult = resultObject.getInt("success");
    } catch (JSONException e) {
        e.printStackTrace();
    }
    return returnedResult;
}
}