我有问题帮帮我啊。。。

import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;

public class StudentData extends JFrame {
  final static int NAME_SIZE = 32;
  final static int GENDER_SIZE = 6;
  final static int RECORD_SIZE =
    (NAME_SIZE + GENDER_SIZE);

  private RandomAccessFile raf;

  private JTextField jtfName = new JTextField(NAME_SIZE);
  private JRadioButton rb1 = new JRadioButton("Male");  
  private JRadioButton rb2 = new JRadioButton("Female");  

  private JButton jbtAdd = new JButton("Add");

  public StudentData() {
    // Open or create a random access file
    try {
      raf = new RandomAccessFile("StudentData.dat", "rw");
    }
    catch(IOException ex) {
      System.out.print("Error: " + ex);
      System.exit(0);
    }

    JPanel p1 = new JPanel();
    p1.setLayout(new GridLayout(1, 2));
    p1.add(new JLabel("Name"));
    p1.add(new JLabel("Gender"));

    JPanel jpGender = new JPanel();
    jpGender.setLayout(new GridLayout(1, 2));
    jpGender.add(rb1);
    jpGender.add(rb2);
   
    ButtonGroup group1 = new ButtonGroup();  
    group1.add(rb1);  
    group1.add(rb2);  

我只能读取name的资料。。。
要怎样才能读取以及保存所选的radio button数值??
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你为radio button创建一个事件监听。
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怎样说呢??
我是新手不太会呢...
可以详解吗??
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