我的方法在負責 Vaadin View 的類中調用。當他們嘗試在主類中調用它進行測試時，一切正常。這是我在 Repository 類中的方法，我的問題是關于 findAll 類：@Repositorypublic class SeansRepository {    @Autowired    JdbcTemplate jdbcTemplate;    public Seans findById(long id) {        return jdbcTemplate.queryForObject("select * from seans where id=? ", new Object[] { id },                new BeanPropertyRowMapper<Seans>(Seans.class));    }    public Collection<Seans> findAll() {        Collection<Seans> seans = (Collection<Seans>) jdbcTemplate.query("select * from seans", new BeanPropertyRowMapper(Seans.class));        return seans;    }    public int deleteById(long id) {        return jdbcTemplate.update("delete from seans where id=?", new Object[] { id });    }}這是在 View 類中調用方法的方式：@DesignRoot@AutoGenerated@SuppressWarnings("serial")public class ChoseNumberOfTicketsView extends AbsoluteLayout implements View{    protected TextField nameTextField;    protected TextField surnameTextField;    protected Label menuLabel;    protected TextField emailTextField;    protected TextField dticketsTextField;    protected TextField nticketsTextField;    protected ComboBox<Seans> movieComboBox;    private SeansRepository repository;    public ChoseNumberOfTicketsView() {        Design.read(this);          repository = new SeansRepository();        movieComboBox = new ComboBox<>("Chose the movie");        movieComboBox.setItems(repository.findAll());    }}我正在嘗試獲取電影列表并將其放在 ComboBox 中以供選擇。我正在添加一個 UI 類，其中包含我的視圖實例：@SpringUIpublic class KinoUI extends UI{    Navigator navigator;    @Override    protected void init(VaadinRequest request) {        getPage().setTitle("Exam");        navigator = new Navigator(this, this);        navigator.addView("", new StartView());        navigator.addView("chosenumberoftickets",  new ChoseNumberOfTicketsView());    }}