Server.java

import java.net.*;
import java.io.*;

public class Server{
    ServerSocket server;
    Socket socket;
    BufferedReader br;
    PrintWriter out;

    public Server()
    {
       try{
           server = new ServerSocket(5555); 
            System.out.println("server is ready to accept connection");
            System.out.println("waiting...");
            socket = server.accept();     
            
            br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            out = new PrintWriter(socket.getOutputStream());

            startReading();
            startWriting();
        } catch (Exception e){
           e.printStackTrace();
       }
    }

    public void startReading(){
       Runnable r1 = ()->{
          System.out.println("reader started..");
          try{
          while(true){
             
              String msg =br.readLine();
              if(msg.equals("exit")){
                System.out.println("client terminate the chat");
                socket.close();
                break;
              }
              System.out.println("client : "+msg);
            
          }
        }catch (Exception e){
            System.out.println("connection is closed");
            // e.printStackTrace();
        }
        };
        new Thread(r1).start();
    }

    public void startWriting(){
       Runnable r2 =()->{
           System.out.println("writer started...");
           try{
           while(!socket.isClosed()){
           
            BufferedReader br1 = new BufferedReader(new InputStreamReader(System.in));
            String context = br1.readLine();
            out.println(context);
            out.flush();

            if(context.equals("exit")){
                socket.close();
                break;
            }
            
           

         }
        }catch(Exception e){
            System.out.println("connection is closed");
            // e.printStackTrace();
        }
        
       };
        new Thread(r2).start();
    }
    public static void main(String[]args){
        System.out.println("this is server ... gojng to start");
        new Server();  
    }
}