import java.awt.Container;
import java.awt.GridLayout;
import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JRadioButton;
public class SwingRadioButtonTest {
public static void main(String args[]) {
JFrame frame = new JFrame();
Container contentPane = frame.getContentPane();
contentPane.setLayout(new GridLayout(0, 1));
ButtonGroup group = new ButtonGroup();
JRadioButton option = new JRadioButton("French Fries", true);
group.add(option);
contentPane.add(option);
option = new JRadioButton("Onion Rings", false);
group.add(option);
contentPane.add(option);
option = new JRadioButton("Ice Cream", false);
group.add(option);
contentPane.add(option);
frame.setSize(200, 200);
frame.show();
}
}