import java.awt.BorderLayout;
import java.awt.Component;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main {
public static void main(String[] argv){
JFrame f = new JFrame();
f.setLayout(new BorderLayout());
JPanel panel = new JPanel();
JButton button = new JButton("A-ha!");
button.setAlignmentX(Component.CENTER_ALIGNMENT);
panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS));
panel.add(Box.createVerticalGlue());
panel.add(button);
panel.add(Box.createVerticalGlue());
f.getContentPane().add(panel);
f.setVisible(true);
}
}