@Override
  public HivePolicyProvider getHivePolicyProvider() throws HiveAuthzPluginException {
    return null;
  }
Abstract class that extends HiveAuthorizer. This will help to shield
Hive authorization implementations from some of the changes to HiveAuthorizer
interface by providing default implementation of new methods in HiveAuthorizer
when possible.
ql/src/java/org/apache/hadoop/hive/ql/security/authorization/plugin/AbstractHiveAuthorizer.java