rocketmq 之namesrv（三十八）mqclient admin请求处理查看broker的状态数据

查看broker的状态数据 AdminBrokerProcessor#ViewBrokerStatsData

这里ViewBrokerStatsData方法命名不符合规范，没看出来为啥必须要用这个方法名
AdminBrokerProcessor#processRequest#this.ViewBrokerStatsData(ctx, request)

 private RemotingCommand ViewBrokerStatsData(ChannelHandlerContext ctx,
        RemotingCommand request) throws RemotingCommandException {
        final ViewBrokerStatsDataRequestHeader requestHeader =
            (ViewBrokerStatsDataRequestHeader) request.decodeCommandCustomHeader(ViewBrokerStatsDataRequestHeader.class);
        final RemotingCommand response = RemotingCommand.createResponseCommand(null);
        MessageStore messageStore = this.brokerController.getMessageStore();

        /**从缓存中获取broker的状态数据*/
        StatsItem statsItem = messageStore.getBrokerStatsManager().getStatsItem(requestHeader.getStatsName(), requestHeader.getStatsKey());
        if (null == statsItem) {
            response.setCode(ResponseCode.SYSTEM_ERROR);
            response.setRemark(String.format("The stats <%s> <%s> not exist", requestHeader.getStatsName(), requestHeader.getStatsKey()));
            return response;
        }

        BrokerStatsData brokerStatsData = new BrokerStatsData();
        /**这里方法块的作用是限定变量生命周期，及早释放，提高内存利用率*/
        {
            BrokerStatsItem it = new BrokerStatsItem();
            StatsSnapshot ss = statsItem.getStatsDataInMinute();
            it.setSum(ss.getSum());
            it.setTps(ss.getTps());
            it.setAvgpt(ss.getAvgpt());
            brokerStatsData.setStatsMinute(it);
        }

        {
            BrokerStatsItem it = new BrokerStatsItem();
            StatsSnapshot ss = statsItem.getStatsDataInHour();
            it.setSum(ss.getSum());
            it.setTps(ss.getTps());
            it.setAvgpt(ss.getAvgpt());
            brokerStatsData.setStatsHour(it);
        }

        {
            BrokerStatsItem it = new BrokerStatsItem();
            StatsSnapshot ss = statsItem.getStatsDataInDay();
            it.setSum(ss.getSum());
            it.setTps(ss.getTps());
            it.setAvgpt(ss.getAvgpt());
            brokerStatsData.setStatsDay(it);
        }

        response.setBody(brokerStatsData.encode());
        response.setCode(ResponseCode.SUCCESS);
        response.setRemark(null);
        return response;
    }

BrokerStatsManager#getStatsItem

public StatsItem getStatsItem(final String statsName, final String statsKey) {
        try {
            return this.statsTable.get(statsName).getStatsItem(statsKey);
        } catch (Exception e) {
        }

        return null;
    }