basic java SocketServer sample code

= server =
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class SampleServer {
 
  public void startServer() {
    int port = 9999;
    try {
      ServerSocket serverSocket = new ServerSocket(port);
      while (true) {
        Socket socket = serverSocket.accept();
        BufferedReader is = new BufferedReader(
            new InputStreamReader(socket.getInputStream()));
        PrintWriter os = new PrintWriter(socket.getOutputStream());
        BufferedReader sin = new BufferedReader(new InputStreamReader(System.in));
        String line = is.readLine();
        System.out.println("Client: " + line);
        while (!line.equals("bye")) {
          sendOne(os, line);
          line = is.readLine();
        }
        os.close();
        is.close();
        socket.close();
        serverSocket.close();
      }
    } catch (Exception e) {
      System.out.println(e.getMessage());
    }
  }
 
  protected void sendOne(PrintWriter os, String line) {
    os.println(line);
    os.flush();
    System.out.println("Server: " + line);
  }
 

  /**
   * @param args
   */
  public static void main(String[] args) {
    // TODO Auto-generated method stub
    SampleServer ss = new SampleServer();
    ss.startServer();
  }

}



= client =
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;

public class SampleClient {
  public void startClient() {
    try {
      Socket socket = new Socket("127.0.0.1", 9999);
      BufferedReader sin = new BufferedReader(new InputStreamReader(System.in));
      PrintWriter os = new PrintWriter(socket.getOutputStream());
      BufferedReader is = new BufferedReader(
          new InputStreamReader(socket.getInputStream()));
      String readline = sin.readLine();
      while (!readline.equals("bye")) {
        sendOne(os, readline);
        System.out.println(is.readLine());
        readline = sin.readLine();
      }
      os.println(readline);
      os.flush();
      os.close();
      is.close();
      socket.close();
    } catch (Exception e) {
      System.out.println("Error " + e);
    }
  }
 
  protected void sendOne(PrintWriter os, String readline) {
    os.println(readline);
    os.flush();
    System.out.println("Client: " + readline);
  }

  /**
   * @param args
   */
  public static void main(String[] args) {
    // TODO Auto-generated method stub
    SampleClient sc = new SampleClient();
    sc.startClient();
  }

}