import java.io.*; import java.net.*; class Thr extends Thread { Socket s; Thr(){s=null; } Thr(Socket s1) { s=s1;} public void run() { String clientSentence; String capitalizedSentence; try{ BufferedReader inFromClient =new BufferedReader(new InputStreamReader(s.getInputStream())); DataOutputStream outToClient=new DataOutputStream(s.getOutputStream()); clientSentence = inFromClient.readLine(); System.out.println(clientSentence); capitalizedSentence = clientSentence.toUpperCase() + '\n'; outToClient.writeBytes(capitalizedSentence); s.close(); if(clientSentence.equals("exit")) System.exit(1); } catch(Exception e){} } } class TCPServer { public static void main(String argv[]) throws Exception { ServerSocket dataReceive = new ServerSocket(4444); while(true) { Socket connectionSocket = dataReceive.accept(); Thr t=new Thr(connectionSocket); t.start(); } } }