public class AsyncTaskDatabase {
    public final static String TAG = "AsyncTaskDatabase";
    private Context context;
    private UserDao userDao;
    private User user;
    private List<User> users;

    public AsyncTaskDatabase(Context context){
        this.context = context;
        AppDatabase db = Room.databaseBuilder(context,
                AppDatabase.class, "database-name").fallbackToDestructiveMigration().build();
        userDao = db.userDao();
    }

    public void inserUser(final User user){
        new AsyncTask<User, Void, Void>(){

            @Override
            protected Void doInBackground(User... users) {
                userDao.insert(user);
                return null;
            }
        }.execute();
    }

    public User getUser(){
        new AsyncTask<Void, Void, User>(){
            @Override
            protected User doInBackground(Void... voids) {
                user = userDao.getUser();
                return null;
            }

            @Override
            protected void onPostExecute(User user) {
                super.onPostExecute(user);
            }
        }.execute();
        return user;
    }

    public List<User> getAll(){
        new AsyncTask<Void, Void, List<User>>(){
            @Override
            protected List<User> doInBackground(Void... voids) {
                users = userDao.getAll();
                return null;
            }

            @Override
            protected void onPostExecute(List<User> users) {
                super.onPostExecute(users);
            }
        }.execute();
        Log.i(TAG, "getAll: " + users.toString());
        return users;
    }

}