Zk是怎么读取myid文件的

dataDir=/data/zookeeper
dataLogDir=/data/zookeeper/version-2
# the port at which the clients will connect
clientPort=2181


server.1=10.243.55.100:2888:3888
server.2=10.243.55.101:2888:3888
server.3=10.243.55.102:2888:3888

　　　　　　  File myIdFile = new File(dataDir, "myid");//你敢相信嘛 zk竟然用最low的File，而没有用nio，而且myid文件名固定
            if (!myIdFile.exists()) {
                throw new IllegalArgumentException(myIdFile.toString()
                        + " file is missing");
            }
            BufferedReader br = new BufferedReader(new FileReader(myIdFile));
            String myIdString;
            try {
                myIdString = br.readLine();//只读第一行
            } finally {
                br.close();
            }
            try {
                serverId = Long.parseLong(myIdString);
                MDC.put("myid", myIdString);