如何使用JComboBox制作日历？

import javax.swing.*;
import javax.swing.table.DefaultTableModel;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.time.YearMonth;

public class CalendarApp extends JFrame {
    private JComboBox<Integer> yearComboBox;
    private JComboBox<String> monthComboBox;
    private JPanel calendarPanel;
    private JTable calendarTable;

    public CalendarApp() {
        setTitle("Calendar App");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLayout(new BorderLayout());

        // 创建年份选择的JComboBox
        yearComboBox = new JComboBox<>();
        int currentYear = YearMonth.now().getYear();
        for (int year = currentYear - 10; year <= currentYear + 10; year++) {
            yearComboBox.addItem(year);
        }

        // 创建月份选择的JComboBox
        monthComboBox = new JComboBox<>();
        String[] months = {"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"};
        for (String month : months) {
            monthComboBox.addItem(month);
        }

        // 创建日历显示的JPanel
        calendarPanel = new JPanel(new BorderLayout());

        // 添加年份和月份选择的JComboBox到主界面
        JPanel selectionPanel = new JPanel();
        selectionPanel.add(yearComboBox);
        selectionPanel.add(monthComboBox);
        add(selectionPanel, BorderLayout.NORTH);

        // 添加日历显示的JPanel到主界面
        add(calendarPanel, BorderLayout.CENTER);

        // 监听年份和月份选择的JComboBox的选择事件
        yearComboBox.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                updateCalendar();
            }
        });

        monthComboBox.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                updateCalendar();
            }
        });

        // 初始化日历显示
        updateCalendar();

        pack();
        setVisible(true);
    }

    private void updateCalendar() {
        int year = (int) yearComboBox.getSelectedItem();
        int month = monthComboBox.getSelectedIndex() + 1;
        YearMonth yearMonth = YearMonth.of(year, month);
        int daysInMonth = yearMonth.lengthOfMonth();

        // 创建日期数据
        Object[][] data = new Object[6][7];
        int day = 1;
        for (int row = 0; row < 6; row++) {
            for (int col = 0; col < 7; col++) {
                if (row == 0 && col < yearMonth.atDay(1).getDayOfWeek().getValue() % 7) {
                    data[row][col] = "";
                } else if (day > daysInMonth) {
                    data[row][col] = "";
                } else {
                    data[row][col] = day;
                    day++;
                }
            }
        }

        // 创建数据模型
        DefaultTableModel model = new DefaultTableModel(data, new String[]{"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"});

        // 创建日历表格
        calendarTable = new JTable(model);
        calendarTable.setRowHeight(30);
        calendarTable.setDefaultRenderer(Object.class, new CalendarCellRenderer());

        // 更新日历显示的JPanel
        calendarPanel.removeAll();
        calendarPanel.add(new JScrollPane(calendarTable), BorderLayout.CENTER);
        calendarPanel.revalidate();
        calendarPanel.repaint();
    }

    private class CalendarCellRenderer extends DefaultTableCellRenderer {
        @Override
        public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
            super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);

            if (value != null) {
                int day = (int) value;
                if (day == YearMonth.now().getDayOfMonth()) {
                    setForeground(Color.RED);
                } else {
                    setForeground(Color.BLACK);
                }
            }

            return this;
        }
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new CalendarApp();
            }
        });
    }
}