@Override
    protected Configuration initialValue() {
      return new HiveConf(AuthorizationPreEventListener.class);
    }
AuthorizationPreEventListener : A MetaStorePreEventListener that
performs authorization/authentication checks on the metastore-side.

Note that this can only perform authorization checks on defined
metastore PreEventContexts, such as the adding/dropping and altering
of databases, tables and partitions.
ql/src/java/org/apache/hadoop/hive/ql/security/authorization/AuthorizationPreEventListener.java