public GroupList queryTopicConsumeByWho(final String addr, final String topic, final long timeoutMillis)
        throws RemotingConnectException, RemotingSendRequestException, RemotingTimeoutException, InterruptedException,
        MQBrokerException {
        QueryTopicConsumeByWhoRequestHeader requestHeader = new QueryTopicConsumeByWhoRequestHeader();
        requestHeader.setTopic(topic);

        RemotingCommand request = RemotingCommand.createRequestCommand(RequestCode.QUERY_TOPIC_CONSUME_BY_WHO, requestHeader);
        RemotingCommand response = this.remotingClient.invokeSync(MixAll.brokerVIPChannel(this.clientConfig.isVipChannelEnabled(), addr),
            request, timeoutMillis);
        switch (response.getCode()) {
            case ResponseCode.SUCCESS: {
                GroupList groupList = GroupList.decode(response.getBody(), GroupList.class);
                return groupList;
            }
            default:
                break;
        }

        throw new MQBrokerException(response.getCode(), response.getRemark(), addr);
    }
@Test
    public void assertQueryTopicConsumeByWho() throws RemotingException, InterruptedException, MQBrokerException {
        mockInvokeSync();
        GroupList responseBody = new GroupList();
        responseBody.getGroupList().add("");
        setResponseBody(responseBody);
        GroupList actual = mqClientAPI.queryTopicConsumeByWho(defaultBrokerAddr, defaultTopic, defaultTimeout);
        assertNotNull(actual);
        assertEquals(1, actual.getGroupList().size());
    }