网络编程：TCP实现客户端并发登录

刺骨的言语ヽ痛彻心扉 2021-10-01 01:50 409阅读 0赞

【需求】：TCP实现客户端并发登录

> 1.客户端通过键盘录入用户名  
> 2.服务端对用户名进行校验：如果该用户存在，服务端显示“XXX，已登录”，并在客户端显示“XXX,欢迎登录”  
> 如果该用户不存在，服务端显示“XXX，尝试登录”，并在客户端显示“XXX,该用户不存在”  
> 3.每个用户最多登录三次

【代码】：

import java.io.*;
    import java.net.*;
    class LoginClient
    {
    	public static void main(String[] args) throws Exception
    	{
    		Socket s=new Socket("127.0.0.1",10008);
    		//键盘录入
    		BufferedReader bufr=new BufferedReader(new InputStreamReader(System.in));
    		//输出
    		PrintWriter out=new PrintWriter(s.getOutputStream(),true);
    		//输入
    		BufferedReader in=new BufferedReader(new InputStreamReader(s.getInputStream()));
    		for(int i=0;i<3;i++){
    			String line=bufr.readLine();
    			if(line==null)
    				break;
    			out.println(line);
    
    			String info=in.readLine();
    			if(info.contains("欢迎"))  break;
    			System.out.println("info:"+info);
    		}
    		bufr.close();
    		s.close();
    	}
    }
    
    class  ServerThread implements Runnable
    {
    	private Socket s;
    	ServerThread(Socket s){
    		this.s=s;
    	}
    	public void run() 
    	{
    		String ip=s.getInetAddress().getHostAddress();
    		try{
    			for(int i=0;i<3;i++){
    				BufferedReader bufr=new BufferedReader(new FileReader("D:\\WorkSpace\\网络编程\\studentInfo.txt"));
    				BufferedReader in=new BufferedReader(new InputStreamReader(s.getInputStream()));
    				PrintWriter out=new PrintWriter(s.getOutputStream(),true);
    				String line=null;
    				String name=in.readLine();
    				boolean flag=false;
    				while((line=bufr.readLine())!=null){
    					if(name.equals(line)){
    						flag=true;
    						break;
    					}
    				}
    				if(flag){
    					System.out.println(name+",已登录");
    					out.println(name+",欢迎登录");
    					break;
    				}else{
    					System.out.println(name+",尝试登录");
    					out.println(name+",该用户不存在");
    				}
    				bufr.close();
    			}
    			s.close();
    		}
    		catch(Exception e){
    			throw new RuntimeException(ip+"校验失败");
    		}
    	}
    }
    
    class  LoginServer
    {
    	public static void main(String[] args) throws Exception
    	{
    		ServerSocket ss=new ServerSocket(10008);
    		while(true){
    			Socket s=ss.accept();
    			new Thread(new ServerThread(s)).start();
    		}
    	}
    }

【截图】：

![20190811173154878.png][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1RoZV9CZXN0X0hhY2tlcg_size_16_color_FFFFFF_t_70][]

[20190811173154878.png]: /images/20210811/55a481e35a0e4c2ebaf89149d78f4834.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1RoZV9CZXN0X0hhY2tlcg_size_16_color_FFFFFF_t_70]: /images/20210811/35a876d3651c49bfbf170af3f4acd892.png