code: private HashMap<String, String> createAuthorizationParams() {
  
          HashMap<String, String> params = new HashMap<>(3);
          params.put("response_type", "code");
          params.put("client_id", preferences.clientId.get());
          params.put("redirect_uri", HTTP_LOCALHOST);
  
          return params;
      }
docs: Generate the params that will be used during the authorization phase
  @return Map with all the params