Set JCheckBox to selected in Java

import java.awt.FlowLayout;
/*w  w  w . j  a  v a 2 s  .c  om*/
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class Main {

  public static void main(String[] args) {

    JFrame frame = new JFrame("JCheckBox Test");
    frame.setLayout(new FlowLayout());
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JCheckBox ac = new JCheckBox("A/C");
    ac.setSelected(true);
    
    JCheckBox cdPlayer = new JCheckBox("A");
    JCheckBox cruiseControl = new JCheckBox("B");
    JCheckBox keylessEntry = new JCheckBox("C");
    JCheckBox antiTheft = new JCheckBox("D");
    JCheckBox centralLock = new JCheckBox("E");

    frame.add(new JLabel("Car Features"));
    frame.add(ac);
    frame.add(cdPlayer);
    frame.add(cruiseControl);
    frame.add(keylessEntry);
    frame.add(antiTheft);
    frame.add(centralLock);
    frame.pack();
    frame.setVisible(true);
  }
}