Tratarea evenimentelor in aplicatiile Java cu interfata grafica

Contor1.java

package ro.virtualcampus.ev;

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

public class Contor1 extends JFrame implements ActionListener {

    private static final long serialVersionUID = 1L;
    JButton buton;
    JLabel eticheta;
    static int contor = 0;

    public Contor1() {
        super("Contor");
        setLayout(new GridLayout(2, 1));
        setLocation(100, 100);
        buton = new JButton("Apasa!");
        eticheta = new JLabel("", JLabel.CENTER);
        getContentPane().add(buton);
        getContentPane().add(eticheta);
        buton.addActionListener(this);
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getActionCommand().equals("Apasa!")) {
            contor++;
            eticheta.setText(contor + "");
        }
    }

    public static void main(String args[]) {
        Contor1 app = new Contor1();
        app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        app.pack();
        app.setVisible(true);
    }

}