switch(operation){
case CREATE_ROLE:
authorizer.createRole(roleDDLDesc.getName(), null);
break;
case DROP_ROLE:
authorizer.dropRole(roleDDLDesc.getName());
break;
case SHOW_ROLE_GRANT:
boolean testMode = conf.getBoolVar(HiveConf.ConfVars.HIVE_IN_TEST);
List<HiveRoleGrant> roles = authorizer.getRoleGrantInfoForPrincipal(
new HivePrincipal(roleDDLDesc.getName(), getHivePrincipalType(roleDDLDesc.getPrincipalType())));