实现“一对多的自由”聊天程序：

（1）服务器端用户可以和多个客户聊天；

（2）服务器端通过多线程与与每个客户端用户连接；

（3）服务器端线程ID标识客户端用户；其中一方通过控制台输入消息，依次轮流向另一方发送数据。-Achieve " the freedom of one to many"　chat program: (1) server-side user can chat with multiple customers　(2) through a multi-threaded server and each client with the user connection　(3) server-side thread ID identifies the customer end users　one of the parties enter a message through the console, followed in turn send data to the other party.