一个基于Socket Coding的小型聊天应用

import java.io.*;
import java.net.Socket;
import java.util.Scanner;

public class Client {
    public static void main(String[] args) {
        try {
            Socket s = new Socket("localhost", 3000);            
            BufferedReader inputStream = new BufferedReader(new InputStreamReader(s.getInputStream()));            
            BufferedWriter outputStream = new BufferedWriter(new OutputStreamWriter(s.getOutputStream()));            
            String clientMsg;            
            String serverMsg;            

            Scanner sc = new Scanner(System.in);            
            clientMsg = sc.nextLine();            

            while (clientMsg != "bye") {                
              outputStream.write(clientMsg + "\r\n"); 
              outputStream.flush();                
              serverMsg = inputStream.readLine(); 
              System.out.println("serever say：" + serverMsg);                
              clientMsg = sc.nextLine();            
            }        
          } catch (IOException e) {            
              e.printStackTrace();        
          }    
    }
}

public class Server {    
  public static final int port = 3000;    
  public static void main(String[] args) {        
    try {            
      ServerSocket ss= new ServerSocket(port);            
      System.out.println("开始在3000上启动服务器");            
      Socket socket = ss.accept();            
      System.out.println("建立了连接");            
      BufferedReader inputStream = new BufferedReader(new InputStreamReader(socket.getInputStream()));            
      BufferedWriter outputStream = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));            

      String clientMsg;            
      String serverMsg;            

      Scanner sc = new Scanner(System.in);            
      clientMsg = inputStream.readLine();            
      while (clientMsg != "bye") {                
        System.out.println(clientMsg);                
        serverMsg = sc.nextLine();                
        outputStream.write(serverMsg + "\r\n");                
        outputStream.flush();                

        clientMsg = inputStream.readLine();            
      }        
    }catch (IOException e) {            
      e.printStackTrace();        
    }    
  }
}

这里有一个注意点，就是Server和Client的Port必须保持一致。并且，有时候设定的端口号不起作用，因为电脑上运行的其他程序可能已经把这个端口号占用了，这时候就需要换一个端口号。