Thread: can we use the Action Listener in a awt without using constructors? clarify the following error?

ClickMe2.java:21: non-static variable button1 cannot be referenced from a static context
button1 = new JButton("Click Me!");
^
ClickMe2.java:22: non-static variable cl cannot be referenced from a static context
button1.addActionListener(cl);
^
ClickMe2.java:22: non-static variable button1 cannot be referenced from a static context
button1.addActionListener(cl);
^
ClickMe2.java:23: non-static variable button1 cannot be referenced from a static context
panel1.add(button1);
^
4 errors

Code:

import javax.swing.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class ClickMe2
{
	public static void main(String [] args)
	{
	new ClickMe2();
	}
	private JButton button1;
	public ClickMe2()
	{
		JFrame f=new JFrame();
		f.setSize(200,100);
		f.setDefaultCloseOperation(
		JFrame.EXIT_ON_CLOSE);
		f.setTitle("I’m Listening");
		ClickListener cl = new ClickListener(); 
		JPanel panel1 = new JPanel(); 
		button1 = new JButton("Click Me!"); 
		    button1.addActionListener(cl); 
		    panel1.add(button1); 
		    f.add(panel1); 
		f.setVisible(true);
	}
 class ClickListener
implements ActionListener
{
	private int clickCount = 0;
	public void actionPerformed(ActionEvent e)
	{
		if (e.getSource() == button1)
		{
		clickCount++;
		if (clickCount == 1)
		button1.setText("I’ve been clicked!");
		else
		button1.setText("I’ve been clicked "
		+ clickCount + " times!");
	}
}
}
}