有人可以详细解释一下这段代码吗

辛苦各位了TT

        JOptionPane.showMessageDialog(this,"测试得分:" + score + "\n测试评语:" + comment);
        System.exit(0);
    }

 
public class TestFrame extends JFrame {//窗体类，继承了JFrame
    Exam exam;//一些成员变量
    Student student;
    JPanel[] panels;
    JLabel timeLabel;
    JButton button;
    boolean timeOver = false;
 
    public TestFrame(Student student) {//构造函数
        this.student = student;//形参保存至成员变量
        exam = Database.getOneExam();//初始化试卷
        setLayout(null);//挂起布局逻辑
        setTitle("在线心理测试");//设置窗口标题
        setResizable(false);//不可修改窗口大小
        setLocationRelativeTo(null);//设置居中显示
        setSize(700, 640);//设置窗口大小
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//关闭按钮退出程序
        initComponents();//执行函数
        new TimingThread().start();//启动timer
        setVisible(true);//设置可见
    }
 
    //初始化控件
    //这都是窗体布局，你亲自运行一下看看效果会比较好，干讲没什么概念
    public void initComponents() {
        JPanel tipPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
        tipPanel.setBounds(0,0,getWidth(),50);
        add(tipPanel);
 
        timeLabel = new JLabel("考试时间:");
        timeLabel.setFont(new Font("微软雅黑",Font.BOLD,24));
        tipPanel.add(timeLabel);
 
        //盒子+滚动布局
        Box box = Box.createVerticalBox();
        JScrollPane scrollPane = new JScrollPane(box);
        scrollPane.setBounds(0,50,getWidth() - 20,getHeight() - 150);
        add(scrollPane);
 
        //设置20个面板装20道题
        ArrayList<Question> questions = exam.getQuestions();
        panels = new JPanel[20];
        for (int i = 0; i < panels.length; i++) {
            JPanel panel = new JPanel(new FlowLayout());
            panels[i] = panel;
            box.add(panel);
            //获取本题
            Question question = questions.get(i);
            //题目标题标签
            JLabel label = new JLabel((i + 1) + "." + question.getTitle());
            panel.add(label);
            //创建按钮组
            ButtonGroup group = new ButtonGroup();
            JRadioButton[] boxes = new JRadioButton[4];
            for (int j = 0; j < 4; j++) {
                JRadioButton radioButton = new JRadioButton(question.getOption(j));
                group.add(radioButton);
                panel.add(radioButton);
                boxes[j] = radioButton;
            }
        }
 
        button = new JButton("交卷");
        button.setBounds(280,560,100,30);
        add(button);
        button.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                handIn();//点交卷按钮执行的函数
            }
        });
    }
 
    //交卷
    public void handIn(){//这里注释已经够多了，具体哪句看不懂可以粘到网上搜一搜
        ArrayList<Question> questions = exam.getQuestions();
        for (int i = 0; i < panels.length; i++) {
            JPanel panel = panels[i];
            //获取题目
            Question question = questions.get(i);
            //获取面板的子控件
            Component[] components = panel.getComponents();
            for (int j = 1; j < components.length; j++) {
                JRadioButton radioButton = (JRadioButton) components[j];
                if (radioButton.isSelected()){
                    //设置问题答案
                    question.setAnswer(j - 1);
                    break;
                }
            }
        }
 
        if (!timeOver){
            for (Question question : exam.getQuestions()) {
                if(question.getScore() == -1){
                    if(JOptionPane.showConfirmDialog(this,"还有未答的题,确定要交卷吗?") != 0){
                        return;
                    }else {
                        break;
                    }
                }
            }
        }
 
        int score = 0;
        for (Question question : exam.getQuestions()) {
            if (question.getScore() != -1){
                score += question.getScore();
            }
        }
 
        String comment;
        if (score < 10){
            comment = "重度抑郁";
        }else if (score < 30){
            comment = "中度抑郁";
        }else if (score < 50){
            comment = "轻度抑郁";
        }else if (score < 70){
            comment = "心情不好";
        }else{
            comment = "身心健康";
        }
        student.setScore(score);
        student.setComment(comment);
        //添加测评记录
        Database.students.add(student);
        Database.writeData();
        JOptionPane.showMessageDialog(this,"测试得分:" + score + "\n测试评语:" + comment);
        System.exit(0);
    }