private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        up.upload(jTextField1.getText());
        upload = new UploadThread(up,jTextField1.getText());
        UploadThr = new Thread(upload);
        UploadThr.start();     
    }

import java.awt.*;
import java.io.*;
import java.util.StringTokenizer;
import javax.swing.*;
import java.awt.event.*;
 
public class Test extends JFrame
{
             JButton b1=new JButton("Start");
             JTextField t1=new JTextField("",20);
 
               public Test() {
                      super("Simple Program");
                      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                      getContentPane().setLayout(new FlowLayout());
 
                      getContentPane().add(t1);
                      getContentPane().add(b1);
 
                      b1.addActionListener(new ActionListener() {
                            public void actionPerformed(ActionEvent e) {
                                 try {
                                         new AnyAction(t1);
                                       }catch(Exception ex) { }
                             }
                      });
 
                      pack();
                      setVisible(true); 
                }
	public static void main(String[] args) {
		 new Test();
	}
}
class AnyAction extends Thread
{
    JTextField tx;
     int i=0;   
    public AnyAction(JTextField t) {
       tx=t;
       start();          
    }
   public void run() {
          while(true) {
                i++;
                tx.setText("" + i);
          }
   }  
}