Can you get this SwingWorker code to work more than once

Here is a project that works perfectly only the first time. This is what it does on the first button press:

It starts-up with only a "Start" button.

(1) Pressing start displays "Hello World".
(2) The three "for" loops are executed in the code.
(3) "Hello World" disappears.

But, when you press the "Start" button a second time this happens:

(1) Displays "Hello World",

How do you modify the below code so that the second button press matches the first button press.

The code has a button and a label.

After answering the above question, another question that I have is: can you make this code better in any way imaginable.

Thank you,

//Code:
package Test_SwingWorker;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.List;
import javax.swing.SwingWorker;

public class Test_SwingWorker extends javax.swing.JFrame
{
    public Test_SwingWorker()
    {
        initComponents();

        //The "Hello World" label that is not seen on Start-up
        jLabel1.setVisible (false);
        
        final Non_GUI_Stuff task = new Non_GUI_Stuff();
        
        jButton1.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent e)
            {
                //The "Hello World" label that appears when button is pressed
                jLabel1.setVisible (true);
        
                task.execute();
            }
         });
    }
                      
    private void initComponents() {

        jPanel1 = new javax.swing.JPanel();
        jButton1 = new javax.swing.JButton();
        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jButton1.setText("Start");

        jLabel1.setText("Hello World");

        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGap(167, 167, 167)
                .addComponent(jButton1)
                .addGap(51, 51, 51)
                .addComponent(jLabel1)
                .addContainerGap(55, Short.MAX_VALUE))
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jButton1)
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addContainerGap()
                        .addComponent(jLabel1)))
                .addContainerGap(283, Short.MAX_VALUE))
        );

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
        );

        pack();
    }

    public static void main(String args[])
    {
        java.awt.EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                new Test_SwingWorker().setVisible(true);
            }
        });
    }
    
class Non_GUI_Stuff extends SwingWorker<Integer, Integer>
{
  protected Integer doInBackground() throws Exception
  {
      //"for" loops mentioned above
      for (int i = 0;i < 100000; i++)
          for (int i2 = 0;i2 < 100000; i2++);
      for (int i3 = 0;i3 < 100000; i3++);
                 
    return 0;
  }
   
  protected void done()
  {
      //The "Hello World" label that disappears
      jLabel1.setVisible (false);
  }
}
                     
    private javax.swing.JButton jButton1;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JPanel jPanel1;
}