ntddparcticals

//TCPCLIENT

 

import java.io.*;

import java.net.*;

class TCPclient

 public static void main(String args[])throws Exception

 {

  String sentence,modifiedsentence;

  BufferedReader infromuser=new BufferedReader(new InputStreamReader(System.in));

  Socket clientSocket=new Socket("localhost",6789);

  DataOutputStream ToServer =new DataOutputStream(clientSocket.getOutputStream());

  BufferedReader infromserver = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));

  sentence=infromuser.readLine();

  ToServer.writeBytes(sentence+"\n");

  modifiedsentence=infromserver.readLine();

  System.out.println(modifiedsentence);

  clientSocket.close();

 }

 

//TCPSERVER

 

 

import java.net.*;

import java.io.*;

class TCPserver

 public static void main(String args[]) throws Exception

 {

  String clientsentance,capital;

  ServerSocket welcomesocket=new ServerSocket(6789);

  while(true)

  {

   Socket connectionsocket=welcomesocket.accept();

   System.out.println(" Connected");

   BufferedReader infromclient=new BufferedReader(new InputStreamReader(connectionsocket.getInputStream()));

   DataOutputStream outtoclient=new DataOutputStream(connectionsocket.getOutputStream());

   clientsentance=infromclient.readLine();

   System.out.println("From client:"+clientsentance);

   capital=clientsentance.toUpperCase();

   outtoclient.writeBytes("From server:"+capital+ '\n');

  }

 }

}