// 获取Client
   MQClient mqClient = new MQClient(endpoint, accessKey, secretKey);

   // 获取Topic的Consumer  
   MQConsumer consumer = mqClient.getConsumer(namespace, topicName, groupName, "TAG");

do {
    List<Message> messages = null;

    try {
        // 长轮询顺序消费消息, 拿到的消息可能是多个分区的, 一个分区的内的消息一定是顺序的
        // 对于顺序消费，如果一个分区内的消息只要有没有被确认消费成功的，则对于这个分区下次还会消费到相同的消息
        // 对于一个分区，只有所有消息确认消费成功才能消费下一批消息
        // 如果对消费延迟比较敏感，强烈建议使用多线程并发拉取消息
        messages = consumer.consumeMessageOrderly(
                Integer.parseInt(batchSize),
                Integer.parseInt(waitSeconds)
        );
    } catch (Throwable e) {
        e.printStackTrace();
    }
    if (messages == null || messages.isEmpty()) {
        System.out.println(Thread.currentThread().getName() + ": no new message, continue!");
        continue;
    }

    for (Message message : messages) {
        System.out.println("Receive message: " + message);
    }

    {
        List<String> handles = new ArrayList<String>();
        for (Message message : messages) {
            handles.add(message.getReceiptHandle());
        }

        try {
            consumer.ackMessage(handles);
        } catch (Throwable e) {
            if (e instanceof AckMessageException) {
                AckMessageException errors = (AckMessageException) e;
                System.out.println("Ack message fail, requestId is:" + errors.getRequestId() + ", fail handles:");
                if (errors.getErrorMessages() != null) {
                    for (String errorHandle :errors.getErrorMessages().keySet()) {
                        System.out.println("Handle:" + errorHandle + ", ErrorCode:" + errors.getErrorMessages().get(errorHandle).getErrorCode()
                                + ", ErrorMsg:" + errors.getErrorMessages().get(errorHandle).getErrorMessage());
                    }
                }
                continue;
            }
            e.printStackTrace();
        }
    }
} while (true);