udp file transfer java with gui

package udpclientserverapp;

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;


public class Client extends JFrame{
   private final JTextField msgField=new JTextField();
   private final JTextArea msgArea=new JTextArea();
   private DatagramSocket socket;

   public Client(){
      super("UDP Client");
      super.add(msgField, BorderLayout.NORTH);
      super.add(new JScrollPane(msgArea),
         BorderLayout.CENTER);
      super.setSize(new Dimension(450,350));
      super.setVisible(true);
      super.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      msgArea.setEditable(false);

      try{
         socket=new DatagramSocket();
      }catch(SocketException ex){
         System.exit(1);
      }

      msgField.addActionListener((ActionEvent evt) -> {
         try{
            String msg=evt.getActionCommand();
            showMsg("\nSendng message packet: "+msg);
            byte buff[]=msg.getBytes();
            DatagramPacket packetSend=
               new DatagramPacket(buff, buff.length,
               InetAddress.getLocalHost(), 12345);
            socket.send(packetSend);
            showMsg("\nPacket sent");
         }catch(IOException ex){
            showMsg(ex.getMessage());
         }
      });

   }


   public void readyToReceivPacket(){
      while(true){
         try{
            byte buff[]=new byte[128];
            DatagramPacket packet=
               new DatagramPacket(buff,buff.length);
            socket.receive(packet);
            showMsg("\nHost: " + packet.getAddress()
                    + "\nPort: " + packet.getPort()
                    + "\nLength: " + packet.getLength()
                    + "\nData: "
                    + new String(packet.getData()));

         }catch(IOException ex){
            showMsg(ex.getMessage());
         }
      }
   }

   public void showMsg(final String msg) {
      SwingUtilities.invokeLater(() -> {
         msgArea.append(msg);
      });
   }

}

package udpclientserverapp;

public class StartClient {
   public static void main(String[] args) {
      Client client=new Client();
      client.readyToReceivPacket();
   }
}