How to Use Checkboxes?

import java.awt.*;

public class TestCheckbox {

public static void main(String[] args){

Frame f = new Frame("TestCheckboxes");

f.setSize(200,200);

CheckboxGroup cbg = new CheckboxGroup();

Checkbox cb1 = new Checkbox("Checkbox 1", cbg, false);

Checkbox cb2 = new Checkbox("Checkbox 2", cbg, false);

Checkbox cb3 = new Checkbox("Checkbox 3", cbg, true);

f.add(cb1,"North");

f.add(cb2,"Center");

f.add(cb3,"South");

f.show();

}