java不知道如何查找ByRole以返回自定义的用户列表

Question

我正在尝试根据角色列出应用程序中的用户。我的控制器中有一个端点，它试图调用我的userService类。findByRoles方法，但我不知道如何在没有字符串角色的情况下放置我想要的角色（行不通）

管理员控制器。java方法：

@GetMapping(path="/users")
public String showUsers( Model model){
    var userList = (List<User>) userService.findByRoles("ROLE_TEACHER"); // dont know how to pass a role here
    model.addAttribute("userList", userList);
    return "users";
}

用户。java：

@Entity
@Table(name = "user_table", schema = "public")
public class User {

    @Id
    @Column(name = "user_id")
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    private Long user_id;

    @Column(name = "name")
    private String name;

    @Column(name = "username")
    private String username;

    @Column(name = "password")
    private String password;

    @Column(name = "email")
    private String email;

    @Column(name = "confirmed")
    private boolean confirmed;

    @ManyToMany(cascade = {CascadeType.MERGE, CascadeType.PERSIST, CascadeType.DETACH}, fetch = FetchType.EAGER)
    @JoinTable(
            name = "user_role_table",
            joinColumns = @JoinColumn(name = "user_id", referencedColumnName = "user_id"),
            inverseJoinColumns = @JoinColumn(name = "role_id", referencedColumnName = "role_id"))
    private Collection<Role> roles = new HashSet<>();



    /*******************************************
     * Setters and getters
     *******************************************/

    public Long getId() {
        return user_id;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getUsername() {
        return username;
    }

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

    public String getPassword() {
        return password;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getEmail() {
        return email;
    }

    public void setConfirmed(Boolean confirmed) {
        this.confirmed = confirmed;
    }

    public Boolean getConfirmed() {
        return confirmed;
    }

    public void setRoles(Collection roles) {
        this.roles = roles;
    }

    public Collection<Role> getRoles() { return this.roles;
    }
}

用户存储库：

public interface UserRepository extends JpaRepository<User, Long> {
    User findByUsername(String username);
    User findByEmail(String email);
    User findByRoles(Role role);
}

角色还原性：

public interface RoleRepository extends JpaRepository<Role, Long> {

    Role findByName(String name);
}

IUserService。java：

public interface IUserService {

    User registerNewUserAccount(UserDto userDto);

    List<User> findAll();

    Optional<User> findById(Long id);

    User findByRoles(Role role);

    public void delete(Long id);

    public User updateConfirmed(Long id);

}

用户服务。java方法：

@Override
public User findByRoles(Role role) {
    return userRepository.findByRoles(role);
}

有什么建议可以帮助我解决这个问题吗

Answer 1

在对这些类进行了调整之后，我认为解决这个问题最合理的方法是使用roleRepository方法findByName。此外，在userRepository、IUserService&；用于返回列表的UserService（请查看我对此答案的评论）

已更改IUserService。java到：

public interface IUserService {

     User registerNewUserAccount(UserDto userDto);

     List<User> findAll();

     Optional<User> findById(Long id);

     List<User> findAllByRoles(String roles); //Added this new method (VERY IMPORTANT for returning multiple users)

     User findByRoles(String roles);

     public void delete(Long id);

     public User updateConfirmed(Long id);
}

已更改用户服务。java方法，用于：

@Override
public User findByRoles(String roles) {
    return userRepository.findByRoles(roleRepository.findByName(roles)); // Using roleRepository here
}

// Added below findAllbyRoles to return a list

@Override
public List<User> findAllByRoles(String roles){
    return userRepository.findAllByRoles(roleRepository.findByName(roles));
}

更改了管理员控制器。java方法，用于：

@GetMapping(path="/users")
public String showUsers( Model model){
    List<User> userList = userService.findAllByRoles("ROLE_STUDENT");
    userList.addAll(userService.findAllByRoles("ROLE_TEACHER"));
    model.addAttribute("userList", userList);
    return "users";
}