java:再次选择dropdown后，如何单击dropdown中的所有选项

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class DropdownExample {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Dropdown Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        String[] options = {"Option 1", "Option 2", "Option 3"};
        JComboBox<String> dropdown = new JComboBox<>(options);
        dropdown.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                String selectedOption = (String) dropdown.getSelectedItem();
                System.out.println("Selected option: " + selectedOption);

                // 点击下拉菜单中的所有选项
                for (int i = 0; i < dropdown.getItemCount(); i++) {
                    String option = (String) dropdown.getItemAt(i);
                    System.out.println("Clicking option: " + option);
                    // 执行相应的操作
                }
            }
        });

        frame.add(dropdown);
        frame.pack();
        frame.setVisible(true);
    }
}