如何使用java从数据包中删除IP地址

我在一个文件中有这样的文件包格式：srcip、destIP、协议号、帧长度。我只需要得到纸条

49.112.250.206,0.217.206.74,171458 25.82.23.122211.231.164.237,6,46 218.55.186.252211.231.171.101,6,46 36.63.70.74,73.151.138.2,61504 232.60.178.64,78.217.241.214,61504 181.175.235.118,58.57.101.205,61504 133.203.23.94,74.110.251.121,6,1504 ......

使用Stringsplit代替StringTokenizer。

for (List<String> read : readFiles.values())
    {       
        while(last>=0)
        {
            last=1;
            String element=read.get(first);
            StringTokenizer st=new StringTokenizer(element, ",");
            //int token=Integer.parseInt(st.nextToken(","));

            first++;
        }
    }

String tmp[]=element.split(" "); //get one by one

for(String s:tmp) {
    System.out.println(s.split(",")[0]); //get only srcIP
}