无法用长键获取Thymeleaf中的HashMap值

Question

@Controller
public class ThymeleafController {

    private final ListController listController = new ListController();
    private final UserController userController = new UserController();
    private final ItemController itemController = new ItemController();

    @RequestMapping("/user/{user_id}")
    public String user_page(@PathVariable("user_id") long user_id, Model model) {
        // model.addtoAttribute("name", "World");
        UserMetaData user = userController.getUserMetaData(user_id);
        ArrayList<User> users = (ArrayList)userController.allUsers();
        HashMap<Long, String> userMap = new HashMap<Long, String>();

        for (int i = 0; i < users.size(); i++) {
            userMap.put(users.get(i).getId(), users.get(i).getUserName());
        }

        model.addAttribute("user", user);
        model.addAttribute("userMap", userMap);
        return "user";
    }
}

<table class="table table-striped">
  ...
  <tbody>
    <tr th:each="publicList: ${user.public_lists}">
      ...
      <td th:text="${userMap[__${publicList.owner}__]}">Default Owner</td>
      ...
    </tr>
  </tbody>
</table>

但是，在加载模板时，我得到了以下异常。

Caused by: org.springframework.expression.spel.SpelParseException: EL1035E: The value '5760744339537920' cannot be parsed as an int

我不知道为什么要在键为long时将其解析为int。有什么方法可以让Thymeleaf将值解析为长吗？

Answer 1

看起来有两种方法可以让它发挥作用：

<td th:text="${userMap.get(publicList.owner)}">Default Owner</td>

或

<td th:text=${userMap[__${publicList.owner + 'L'}__]}">Default Owner</td>

我会用第一个。我想，在表单的情况下，你必须使用第二个。