如何在JavaFX中为ComboBox添加掩码？

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.ComboBox;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.stage.Stage;
import javafx.util.Callback;

public class ComboBoxMaskExample extends Application {

    @Override
    public void start(Stage primaryStage) {
        ComboBox<String> comboBox = new ComboBox<>();
        comboBox.getItems().addAll("Option 1", "Option 2", "Option 3");

        // 设置CellFactory
        comboBox.setCellFactory(new Callback<ListView<String>, ListCell<String>>() {
            @Override
            public ListCell<String> call(ListView<String> param) {
                return new ListCell<String>() {
                    @Override
                    protected void updateItem(String item, boolean empty) {
                        super.updateItem(item, empty);
                        if (item != null) {
                            // 添加掩码
                            setText("****" + item.substring(4));
                        } else {
                            setText(null);
                        }
                    }
                };
            }
        });

        primaryStage.setScene(new Scene(comboBox, 200, 100));
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}