Java 如何在JFrame中声明类（包含SACache Poi）的对象

所以我一直在开发一个程序，搜索excel文件。所以我创建了两个类，一个叫做GUI，另一个叫做

ExcelReader

。当我试图在GUI类中创建

ExcelReader

对象时，GUI程序崩溃。下面是我的GUI代码：

public class GUI {

    private JFrame frmExcelReader;
    private JTextField textField;
    private JTextField textField_1;
    private JTextField textField_2;
    private JTextField textField_3;
    private JTextField textField_4;
    private JTextField textField_5;
    private static ExcelReader excelreader;
    private JTextField textField_6;
    private JTextField textField_7;
    private JTextField textField_8;
    private JTextField textField_9;
    private JTextField textField_10;
    private JTextField textField_11;
    private JTextField textField_12;
    private JTextField textField_13;
    private JTextField textField_14;
    private JTextField textField_15;
    private JTextField textField_16;
    private JTextField textField_17;
    private JTextField textField_18;
    private JTextField textField_19;
    private JLabel lblLocation;

    /**
     * Launch the application.
     *
     * @throws IOException
     */
    public static void main(String[] args) throws IOException {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    GUI window = new GUI();
                    window.frmExcelReader.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the application.
     *
     * @throws IOException
     */
    public GUI() throws IOException {
        initialize();
    }

    /**
     * Initialize the contents of the frame.
     *
     * @throws IOException
     */
    private void initialize() throws IOException {
        frmExcelReader = new JFrame();
        excelreader = new ExcelReader();
        frmExcelReader.setFont(new Font("Dialog", Font.BOLD, 26));
        frmExcelReader.setAutoRequestFocus(false);
        frmExcelReader.setTitle("Excel Reader\n");
        frmExcelReader.getContentPane().setBackground(Color.ORANGE);
        frmExcelReader.setBounds(100, 100, 674, 432);
        frmExcelReader.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frmExcelReader.getContentPane().setLayout(null);

        textField = new JTextField();
        textField.setBounds(131, 45, 367, 32);
        frmExcelReader.getContentPane().add(textField);
        textField.setColumns(10);

        textField_1 = new JTextField();
        textField_1.setColumns(10);
        textField_1.setBounds(131, 95, 367, 32);
        frmExcelReader.getContentPane().add(textField_1);

        JButton btnNewButton = new JButton("Search");
        btnNewButton.setBounds(495, 48, 117, 29);
        frmExcelReader.getContentPane().add(btnNewButton);

        JButton button = new JButton("Search");
        button.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
            }
        });
        button.setBounds(495, 98, 117, 29);
        frmExcelReader.getContentPane().add(button);

        textField_2 = new JTextField();
        textField_2.setBounds(66, 189, 251, 26);
        frmExcelReader.getContentPane().add(textField_2);
        textField_2.setColumns(10);

        textField_3 = new JTextField();
        textField_3.setBounds(66, 251, 251, 26);
        frmExcelReader.getContentPane().add(textField_3);
        textField_3.setColumns(10);

        textField_4 = new JTextField();
        textField_4.setBounds(66, 220, 251, 26);
        frmExcelReader.getContentPane().add(textField_4);
        textField_4.setColumns(10);

        textField_5 = new JTextField();
        textField_5.setBounds(66, 282, 251, 26);
        frmExcelReader.getContentPane().add(textField_5);
        textField_5.setColumns(10);

        JLabel lblProductName = new JLabel("Product Name");
        lblProductName.setBounds(31, 53, 98, 16);
        frmExcelReader.getContentPane().add(lblProductName);

        JLabel lblModelName = new JLabel("Model Number");
        lblModelName.setBounds(21, 103, 98, 16);
        frmExcelReader.getContentPane().add(lblModelName);

        JLabel lblProductName_1 = new JLabel("Product Name");
        lblProductName_1.setBounds(98, 161, 109, 16);
        frmExcelReader.getContentPane().add(lblProductName_1);

        textField_6 = new JTextField();
        textField_6.setBounds(66, 313, 251, 26);
        frmExcelReader.getContentPane().add(textField_6);
        textField_6.setColumns(10);

        textField_7 = new JTextField();
        textField_7.setBounds(66, 344, 251, 26);
        frmExcelReader.getContentPane().add(textField_7);
        textField_7.setColumns(10);

        textField_8 = new JTextField();
        textField_8.setBounds(329, 189, 66, 26);
        frmExcelReader.getContentPane().add(textField_8);
        textField_8.setColumns(10);

        textField_9 = new JTextField();
        textField_9.setColumns(10);
        textField_9.setBounds(405, 189, 130, 26);
        frmExcelReader.getContentPane().add(textField_9);

        textField_10 = new JTextField();
        textField_10.setColumns(10);
        textField_10.setBounds(329, 220, 66, 26);
        frmExcelReader.getContentPane().add(textField_10);

        textField_11 = new JTextField();
        textField_11.setColumns(10);
        textField_11.setBounds(329, 251, 66, 26);
        frmExcelReader.getContentPane().add(textField_11);

        textField_12 = new JTextField();
        textField_12.setColumns(10);
        textField_12.setBounds(329, 282, 66, 26);
        frmExcelReader.getContentPane().add(textField_12);

        textField_13 = new JTextField();
        textField_13.setColumns(10);
        textField_13.setBounds(329, 313, 66, 26);
        frmExcelReader.getContentPane().add(textField_13);

        textField_14 = new JTextField();
        textField_14.setColumns(10);
        textField_14.setBounds(329, 344, 66, 26);
        frmExcelReader.getContentPane().add(textField_14);

        textField_15 = new JTextField();
        textField_15.setColumns(10);
        textField_15.setBounds(405, 220, 130, 26);
        frmExcelReader.getContentPane().add(textField_15);

        textField_16 = new JTextField();
        textField_16.setColumns(10);
        textField_16.setBounds(405, 251, 130, 26);
        frmExcelReader.getContentPane().add(textField_16);

        textField_17 = new JTextField();
        textField_17.setColumns(10);
        textField_17.setBounds(405, 282, 130, 26);
        frmExcelReader.getContentPane().add(textField_17);

        textField_18 = new JTextField();
        textField_18.setColumns(10);
        textField_18.setBounds(405, 313, 130, 26);
        frmExcelReader.getContentPane().add(textField_18);

        textField_19 = new JTextField();
        textField_19.setColumns(10);
        textField_19.setBounds(405, 344, 130, 26);
        frmExcelReader.getContentPane().add(textField_19);

        JLabel lblQty = new JLabel("QTY");
        lblQty.setBounds(351, 161, 61, 16);
        frmExcelReader.getContentPane().add(lblQty);

        lblLocation = new JLabel("Location");
        lblLocation.setBounds(434, 161, 61, 16);
        frmExcelReader.getContentPane().add(lblLocation);

    }
}

---

我还包括了所有相关的导入，但只是没有在上面的问题中编写。gui冻结还是崩溃？您的excel reader到底在做什么？我们如何知道excel reader类的真正含义，以及调用new ExcelReader（）时执行的代码？？