Java AWT BorderLayout add to top and bottom

import java.awt.BorderLayout;

import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Main extends JFrame {
  private static final String[] names = { "Red", "Green", "Blue", "Purple", "Greenish" };

  public Main() {

    setLayout(new BorderLayout(5, 5));

    JPanel center = new JPanel();
    JPanel bottom = new JPanel();

    add(new JComboBox(names), BorderLayout.NORTH);

    center.add(new JCheckBox("Background"));
    center.add(new JCheckBox("Foreground"));

    add(center, BorderLayout.CENTER);

    bottom.add(new JButton("Ok"));
    bottom.add(new JButton("Cancel"));

    add(bottom, BorderLayout.SOUTH);
  }/*from   w  w w.  j  a va 2s  . c om*/

  public static void main(String[] args) {
    Main gui = new Main();
    gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    gui.setSize(400, 125);
    gui.setVisible(true);
  }
}