@Override
    public boolean hasNext() {
      if (currentAuthorizerPosition < authorizers.size()
          || authorizationProviderPosition < authorizationProviders.size()) {
        return true;
      }
      return false;
    }
Wrapper of policy provider no matter this is in authorizer v1 or v2
ql/src/java/org/apache/hadoop/hive/ql/security/authorization/PolicyProviderContainer.java