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

public class App extends JFrame {
public App() {
super("Fundatec");

JPanel panel = new JPanel();
panel.setLayout( new FlowLayout() );

JButton btn = new JButton("Ok");
btn.addMouseListener( new MouseListener() {

public void mouseEntered(MouseEvent e) {
System.out.print("A");
}

public void mouseExited(MouseEvent e) {
System.out.print("B");
}
public void mouseReleased(MouseEvent e) {
System.out.print("C");
}
public void mousePressed(MouseEvent e) {
System.out.print("D");
}
public void mouseClicked(MouseEvent e) {
System.out.print("E");
}
});

panel.add(btn);
add(panel);
}

static public void main(String[] args) {
App app = new App();
app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
app.setSize( 200, 75 );
app.setVisible( true );
}
}