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我破解了代码，但是我不知道怎么做。完全没有

一方面，编译和运行代码每次都会渲染一个窗口。然后，我工作了大约15分钟，并且帧不再在运行时出现。我尝试撤消工作，添加运行方法，添加主要方法，甚至直接从我的教科书中复制和粘贴代码。没事。

我试图粘贴尽可能少的代码。如果我的代码草率，请原谅我。这是我第一次使用秋千。谢谢！

public class LibraryFrame extends JFrame implements ActionListener
{
    private JScrollPane studentScroller = new JScrollPane();
    private JPanel addStudent = new JPanel();
    private JTextField UID   = new JTextField();
    private JTextField name  = new JTextField();
    private JTextField email = new JTextField();
    private JButton okButton = new JButton("OK");
    private JButton closeButton = new JButton("Close");
    private JPanel buttonPane = new JPanel();

    public LibraryFrame() 
    {

        setTitle("Student Enrollment");
        setSize(500,200);
        setLocationByPlatform(true);


        addStudent.setLayout(new GridLayout(0, 2, 0, 0));
        addStudent.add(new JLabel("Enter Student UID:"));
        addStudent.add(UID);
        addStudent.add(new JLabel("Enter Student Name:"));
        addStudent.add(name);
        addStudent.add(new JLabel("Enter Student Email:"));
        addStudent.add(email);
        addStudent.add(Box.createRigidArea(new Dimension(0, 5)));
        addStudent.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));

        okButton.setActionCommand(null);
        closeButton.addActionListener(new ActionListener() //implement window close only
        {
            @Override
            public void actionPerformed(ActionEvent e) 
            { dispose(); }
        });

        buttonPane.setLayout(new BoxLayout(buttonPane, BoxLayout.LINE_AXIS));
        buttonPane.setBorder(BorderFactory.createEmptyBorder(0, 10, 10, 10));
        buttonPane.add(Box.createRigidArea(new Dimension(0, 0)));
        buttonPane.add(okButton);
        buttonPane.add(Box.createRigidArea(new Dimension(10,  0)));
        buttonPane.add(closeButton);

        Container studentPane = getContentPane();
        studentPane.add(addStudent, BorderLayout.CENTER);
        studentPane.add(buttonPane, BorderLayout.PAGE_END);
        pack();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
        setVisible(true);
    }
}