import java.awt.Color;
import java.awt.BorderLayout;
import java.awt.event.*;
import javax.swing.*;
 
import java.io.*;
import java.net.*;
 
class SocketClient extends JFrame
		 implements ActionListener {
 
   JLabel text, clicked;
   JButton button;
   JPanel panel;
   JTextField textField;
   Socket socket = null;
   PrintWriter out = null;
   BufferedReader in = null;
 
   SocketClient(){ //Begin Constructor
     text = new JLabel("Text to send over socket:");
     textField = new JTextField(20);
     button = new JButton("Click Me");
     button.addActionListener(this);
 
     panel = new JPanel();
     panel.setLayout(new BorderLayout());
     panel.setBackground(Color.white);
     getContentPane().add(panel);
     panel.add("North", text);
     panel.add("Center", textField);
     panel.add("South", button);
   } //End Constructor
 
  public void actionPerformed(ActionEvent event){
     Object source = event.getSource();
 
     if(source == button){
//Send data over socket
          String text = textField.getText();
          out.println(text);
	  textField.setText(new String(""));
//Receive text from server
       try{
	  String line = in.readLine();
          System.out.println("Text received :" + line);
       } catch (IOException e){
	 System.out.println("Read failed");
       	 System.exit(1);
       }
     }
  }
 
  public void listenSocket(){
//Create socket connection
     try{
       socket = new Socket("124.243.213.225", 4444);
       out = new PrintWriter(socket.getOutputStream(), true);
       in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
     } catch (UnknownHostException e) {
       System.out.println("Unknown host: kq6py.eng");
       System.exit(1);
     } catch  (IOException e) {
       System.out.println("No I/O");
       System.exit(1);
     }
  }
 
   public static void main(String[] args){
        SocketClient frame = new SocketClient();
	frame.setTitle("Client Program");
        WindowListener l = new WindowAdapter() {
                public void windowClosing(WindowEvent e) {
                        System.exit(0);
                }
        };
 
        frame.addWindowListener(l);
        frame.pack();
        frame.setVisible(true);
	frame.listenSocket();
  }
}
 

Socket

public Socket(String host,
              int port)
       throws UnknownHostException,
              IOException

    Creates a stream socket and connects it to the specified port number on the named host.

    If the specified host is null it is the equivalent of specifying the address as InetAddress.getByName(null). In other words, it is equivalent to specifying an address of the loopback interface.

    If the application has specified a server socket factory, that factory's createSocketImpl method is called to create the actual socket implementation. Otherwise a "plain" socket is created.

    If there is a security manager, its checkConnect method is called with the host address and port as its arguments. This could result in a SecurityException.

    Parameters:
        host - the host name, or null for the loopback address.
        port - the port number. 
    Throws:
        UnknownHostException - if the IP address of the host could not be determined. 
        IOException - if an I/O error occurs when creating the socket. 
        SecurityException - if a security manager exists and its checkConnect method doesn't allow the operation.
    See Also:
        setSocketImplFactory(java.net.SocketImplFactory), SocketImpl, SocketImplFactory.createSocketImpl(), SecurityManager.checkConnect(java.lang.String, int)

        socket = new Socket("124.243.213.225", 4444);

       socket = new Socket("Tony_Arcos.", 5555);