java中單選框和複選框

package Second;import java.awt.*;import javax.swing.*;import sun.org.mozilla.javascript.internal.Kit;import java.awt.event.*;public class Text2 {/** * @param args */public Label l1=new Label("性別");public Label l2=new Label("學曆");public Label l3=new Label();public JRadioButton s1=new JRadioButton("男");public JRadioButton s2=new JRadioButton("女",true);public JCheckBox s3=new JCheckBox("初中");public JCheckBox s4=new JCheckBox("高中",true);public JCheckBox s5=new JCheckBox("本科");    public JCheckBox s6=new JCheckBox("碩士");public ButtonGroup g=new ButtonGroup();public void display(){JFrame jf=new JFrame("測試程式");    Toolkit kit=Toolkit.getDefaultToolkit();    Dimension screenSize=kit.getScreenSize();    int x=screenSize.height;    int y=screenSize.width;    int xx=(x-200)/2;    int yy=(y-300)/2;jf.setSize(300,200);jf.setVisible(true);jf.setLocation(yy,xx);JPanel pane=new JPanel(new GridLayout(5,2));jf.setContentPane(pane);jf.setResizable(false);    g.add(s1);    g.add(s2);    pane.add(l1);    pane.add(l3);    pane.add(s1);    pane.add(s2);    pane.add(l2);    pane.add(s3);    pane.add(s4);    pane.add(s5);    pane.add(s6);}public static void main(String[] args) {// TODO Auto-generated method stubnew Text2().display();}}