code: private void setExpectedAnswers(ArrayList<String> realms) {
          if (answers == null) {
              return;
          }
  
          for (String realm : realms) {
              try {
                  answers.put(realm, "");
              } catch (JSONException t) {
                  logger.error("setExpectedAnswers failed with exception: " + t.getLocalizedMessage(), t);
              }
          }
      }
docs: Initializes the collection of expected challenge answers.
  
  @param realms List of realms