我在尝试更新用户时出错，但无法使用 SpringBoot 显示我的用户角色

Question

登录后我想做什么，在用户页面中，我试图向所有用户显示他们的角色，当我点击其中一个的编辑时，我会进入 edit_user 页面，我将允许我编辑用户，但我得到这样做时出错，在 usersPage 中我看不到用户的角色。

用户实体：

@Entity
@Table(name = "users" ,uniqueConstraints = @UniqueConstraint(columnNames = "userName"))
public class Users {

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String userName;
private String password;



@ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
@JoinTable(
        name = "users_roles",
        joinColumns = @JoinColumn(
                name = "user_id",referencedColumnName ="id"),
        inverseJoinColumns = @JoinColumn(
                name ="role_id" ,referencedColumnName ="id"
        )

)
private Collection<Roles> roles;


public Users(String userName, String password, Collection<Roles> roles) {
    this.userName = userName;
    this.password = password;
    this.roles = roles;
}
public Users()
{
    super();
}
public Long getId() {
    return id;
}

public void setId(Long id) {
    this.id = id;
}

public String getUserName() {
    return userName;
}

public void setUserName(String userName) {
    this.userName = userName;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public Collection<Roles> getRoles() {
    return roles;
}

用户注册Dto

public class UserRegistrationDto {

private String userName;
private String password;
private Collection<Roles> role;

public UserRegistrationDto(String userName, String password, Collection<Roles> role) {
    this.userName = userName;
    this.password = password;
    this.role = role;
}

public UserRegistrationDto()
{
    super();
}

public String getUserName() {
    return userName;
}

public void setUserName(String userName) {
    this.userName = userName;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public Collection<Roles> getRole() {
    return role;
}

public void setRole(Collection<Roles> role) {
    this.role = role;
}

}

用户控制器

在这个控制器层它负责获取、删除、编辑用户

@Controller
public class UserController {

@Autowired
private UserService userService;

@Autowired
private RoleRepository roleRepository;

public UserController(UserService userService, RoleRepository roleRepository) {
    this.userService = userService;
    this.roleRepository = roleRepository;
}

@ModelAttribute("roles")
public List<Roles> initializeRoles(){
    List<Roles> roles = roleRepository.findAll();
    return roles ;
}

@GetMapping("/users/AllUsers")
public String getAllUsers(Model model)
{
    model.addAttribute("user",userService.getAlluser());
    return "Users/users";
}

@GetMapping("/user/edit/{id}")
public String editUserForm(@PathVariable long id, Model model)
{
    model.addAttribute("user",userService.getUserById(id));

    return "Users/edit_user";
}

@RequestMapping(value = "/user/update/{id}",method = RequestMethod.POST)
public String updateUser(@PathVariable Long id, @ModelAttribute("user") UserRegistrationDto registrationDto)
{
    Users userExisting = userService.getUserById(id);

    userExisting.setId(id);

    userExisting.setUserName(registrationDto.getUserName());

    userExisting.setRoles(registrationDto.getRole());

    userService.updateUser(userExisting);

    return "redirect:/users/AllUsers";

}

@GetMapping("/user/delete/{id}")
public String deleteUser(@PathVariable long id)
{
    userService.deleteUser(id);
    return "redirect:/users/AllUsers";
}

}

用户服务

//save a user from the userRegistration form that been shown in the class model
public Users save(UserRegistrationDto registrationDto)
{
    //Users user = new Users(registrationDto.getUserName(),passwordEncoder.encode(registrationDto.getPassword()),Arrays.asList(new Roles(registrationDto.setRole(registrationDto.getRole()))));;//Arrays.asList(new Roles("ROLE_USER"))

    Users usersEntity = new Users();

    usersEntity.setUserName(registrationDto.getUserName());
    usersEntity.setRoles(registrationDto.getRole());
    usersEntity.setPassword(passwordEncoder.encode(registrationDto.getPassword()));

    return userRepository.save(usersEntity);
}
@Override
public Users getUserById(Long id) {
    return userRepository.findById(id).get();
}
//we converting roles to authorities
private Collection <? extends GrantedAuthority> mapRolesToAuthorities(Collection<Roles> roles) {
    return roles.stream()
            .map(role -> new SimpleGrantedAuthority(role.getName()))
            .collect(Collectors.toList());
}

edit_user.html

      <form th:action="@{/user/update/{id}}" method="post" th:object="${user}">

    <div class="form-group">
      <label class="control-label" for="userName"> Username </label>
      <input id="userName" class="form-control" th:field="*{userName}" required autofocus="autofocus" />
    </div>

    <div class="col-1.5">
      <label th:for="roles"> User Type: </label>
      <select class="form-control form-control-sm" id="roles" name="roles">
        <option value="">Select User Type</option>
        <option th:each = "role: ${roles}"
                th:value="${role.id}"
                th:text="${role.name}"
        >
        </option>
      </select>
    </div>



    <div class="form-group">
      <label class="control-label" for="password"> Password  </label> <input
            id="password" class="form-control" th:field="*{password}" required autofocus="autofocus" type="password" />
    </div>

    <div class="form-group">
      <button type="submit" class="btn btn-success">Submit</button>
    </div>
  </form>

users.html 我将在其中显示所有用户

<section class="table_content">

<!--main-container-part-->
<div id="content">

    <!--End-breadcrumbs-->

    <!--Action boxes-->
    <div class ="container">

        <div class = "row">
            <h1> All Users </h1>
        </div>

        <br>
        <br>

        <table class = "table table-striped table-bordered">
            <thead class = "table-dark">
            <tr>
                <th> Name </th>
                <th> Roles </th>
                <th> Edit </th>
                <th> Delete </th>
            </tr>
            </thead>

            <tbody>

            <tr th:each = "user: ${user}"> <!-- this attribute to list up products  -->

                <td th:text="${user.userName}" ></td>
                <td th:text="${user.roles}"></td>

                <td> <center> <a th:href="@{/user/edit/{id}(id=${user.id})}" style="color: green"> Edit </a> </center> </td>

                <td> <center> <a th:href="@{/user/delete/{id}(id=${user.id}) }" style="color: red"> Delete </a> </center> </td>

            </tr>

            </tbody>

        </table>

    </div>
</div>

Answer 1

您犯的第一个错误是在 edit_user.html 中，正如您提供的堆栈跟踪所说，端点 /user/update/{id} 无法将 '{id}' 转换为 long。 那是因为您传递的 id 不是用户 id，而是字符串 '{id}' 本身。

在 edit_user.html 中更改：

 <form th:action="@{/user/update/{id}}" method="post" th:object="${user}">

到

 <form th:action="@{/user/update/{id}(id=${user.id})}" method="post" th:object="${user}">

如果这仍然不起作用，我建议也将 userID 作为模型中的属性传递。

对于第二个问题，由于 users.html 中的这一行，您无法可视化用户角色：

<td th:text="${user.roles}"></td>

由于 User.roles 是一个集合，它不能“一次”呈现，您必须使用 edit_user 中使用的相同语法，因此：

<td>
    <p th:each="role: ${user.roles}" th:text="${role.name}"></p>
</td>