Public void actionPerfomed(ActionEvent evt)

import javax.swing.*;
import java.awt.event.*;
import java.awt.*;

//implementando ActionListener vc precisa criar o método actionPerformed
public class Teste extends JFrame implements ActionListener
{
    JButton teste = new JButton("Fale!");

     public Teste()
    {
          teste.addActionListener(this); //a sua classe implementa ActionListener
          this.getContentPane().add(teste);
    }

     public void actionPerformed(ActionEvent evt)
    {
        Object ob = evt.getSource();
        if(ob==this.teste)
        {
            System.out.println("Falei!");
        }
    }
}