//server

import java.lang.*;
import java.io.*;
import java.net.*;
import java.lang.Thread.*;

class Server {
   public static void main(String args[]) {
      String data = "test data";
        while(true){
      try {
         ServerSocket srvr = new ServerSocket(1234);
         Socket skt = srvr.accept();
         System.out.print("Server has connected!\n");
         PrintWriter out = new PrintWriter(skt.getOutputStream(), true);
         System.out.print("Sending string: '" + data + "'\n");
         out.print(data);
         out.close();
         skt.close();
         srvr.close();
      }
      catch(Exception e) {
         System.out.print("Whoops! It didn't work!\n");
      }
   }
}
}


//client:


package myclient;

import javax.swing.JFrame.*;
import javax.swing.*;
import java.io.*;
import java.net.*;

public class myclient {

    private static String call = "Call from: ";

  public static void main(  String args[]){
    //new MainFrame("from asterisk");
    String phone = null;

    JFrame fr = new JFrame();
    JButton btn = new JButton("BUTTON");
    JPanel panel = new JPanel();   
    panel.add(btn);
    //panel.add(label);
    panel.setBorder(BorderFactory.createEmptyBorder());
    fr.getContentPane().add(panel);
  //  fr.pack();
//    fr.setVisible(true);


while(true){
    try{
        Socket skt = new Socket("ip", 1234);
        BufferedReader in = new BufferedReader(new InputStreamReader(skt.getInputStream()));
        System.out.print("Received string: '");
        while(!in.ready()) {}

        phone = in.readLine();
        System.out.println(phone);
        System.out.println("'\n");
        //
    JLabel label = new JLabel(call + phone);
    label.setLabelFor(btn);
    panel.add(label);
    fr.pack();
    fr.setVisible(true);
        //

        in.close();
    }
    catch(Exception e){
        System.out.print("Didn't work\n");
    }
   }
  }
}