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

class Teller {
    public static void main (String[] arg) {
	Kontroll kontroll = new Kontroll();
    }
}

class Modell {
    private GUI gui;
    private int tellerverdi = 0;

    Modell (GUI g) {
	gui = g;
    }

    void oekTeller () {
	++tellerverdi;
	gui.visTeller(tellerverdi);
    }

    void nullstillTeller () {
	tellerverdi = 0;
	gui.visTeller(tellerverdi);
    }
}

class GUI {
    private JButton tell, resett, slutt;
    private JFrame vindu;
    private JLabel antall;
    private JPanel panel;
    private Kontroll kontroll;

    GUI (Kontroll k) {
	kontroll = k;
        try {
            UIManager.setLookAndFeel(
                UIManager.getCrossPlatformLookAndFeelClassName());
        } catch (Exception e) { System.exit(1); }

        vindu = new JFrame("Teller");
        vindu.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        panel = new JPanel();
        vindu.add(panel);

        antall = new JLabel("  0  ");

        tell = new JButton(" +1 ");
        class OekTeller implements ActionListener {
            @Override
            public void actionPerformed (ActionEvent e) {
                kontroll.oekTeller();
            }
        }
        tell.addActionListener(new OekTeller());

        resett = new JButton(" = 0 ");
        class Nuller implements ActionListener {
            @Override
            public void actionPerformed (ActionEvent e) {
                kontroll.nullstillTeller();
            }
        }
        resett.addActionListener(new Nuller());

        slutt = new JButton("Exit");
        class Stopper implements ActionListener {
            @Override
            public void actionPerformed (ActionEvent e) {
                kontroll.avslutt();
            }
        }
        slutt.addActionListener(new Stopper());

        panel.add(antall);  panel.add(tell);
	panel.add(resett);  panel.add(slutt);
        vindu.pack();  vindu.setVisible(true);
    }

    void visTeller (int t) {
	antall.setText("  " + t + "  ");
    }
}

class Kontroll {
    private GUI gui;
    private Modell modell;
    
    Kontroll () {
	gui = new GUI(this);
	modell = new Modell(gui);
    }

    void oekTeller () {
	modell.oekTeller();
    }

    void nullstillTeller () {
	modell.nullstillTeller();
    }

    void avslutt () {
	System.exit(0);
    }
}