@Override
  public void grantRole(List<HivePrincipal> hivePrincipals, List<String> roles,
      boolean grantOption, HivePrincipal grantorPrinc) throws HiveAuthzPluginException, HiveAccessControlException {
    accessController.grantRole(hivePrincipals, roles, grantOption, grantorPrinc);
  }
Convenience implementation of HiveAuthorizer.
You can customize the behavior by passing different implementations of
{@link HiveAccessController} and {@link HiveAuthorizationValidator} to constructor.
ql/src/java/org/apache/hadoop/hive/ql/security/authorization/plugin/HiveAuthorizerImpl.java