1.Socket详解
https://blog.csdn.net/sight_/article/details/8138802
https://blog.csdn.net/qq_14996421/article/details/51472718
3.JAVA基于TCP和UDP的网络连接
https://blog.csdn.net/zhengyikuangge/article/details/51002849
原文：https://www.cnblogs.com/1950137408lxj/p/9175503.html