运行ServerData.java 启动服务器，然后服务器处于等待状态

运行LoginData.java 启动(客户端)登陆界面 输入用户名 ip为本机localhost

在登陆后的界面文本框输入文本，然后发送

可以同时启动多个客户端 实现群聊-Running ServerData.java start the server, and the server in a wait state

Running LoginData.java start enter a user name (client) login screen IP-based machine localhost

After landing interface text box to enter text, and then send

Can be active at multiple clients to achieve group chat