单选按钮组件

public class asd extends JFrame{

    public asd() {
        // TODO Auto-generated constructor stub
        Container c = getContentPane();
        setLayout(new GridLayout(2,2,5,5));
        JRadioButton jr1 = new JRadioButton("男");
        JRadioButton jr2 = new JRadioButton("女");
        ButtonGroup group = new ButtonGroup();
        group.add(jr1);
        group.add(jr2);
        c.add(jr1);
        c.add(jr2);
        setSize(300,300);
        setVisible(true);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        new asd();
    }

}