使用@ManyToOne如何將我的一個用戶映射到汽車？

每當用戶添加優惠時，我都會嘗試將所有者（用戶）與優惠（汽車）映射。像下面這樣的設定 user_id 始終為空。我錯過了什么？我認為這與控制器有關。映射對我來說似乎沒問題，但我可能錯了。所有者是登錄并添加報價的人，因此應該通過他的 id 映射。

編輯我發現我的@AuthenticationPrincipal 身份驗證身份始終為空，即使只有經過身份驗證的用戶才能訪問 POST /api/cars 端點。似乎違反直覺

汽車控制器

    @Controller
    public class CarController {

    @Autowired
    private CarService carService;
    
    
    @Autowired
    UserRepository userRepository;
    
    @GetMapping("/api/cars")
    public String getCars(Model model) {
        model.addAttribute("cars", carService.getAllCars());
        return "cars";
    }
    
    @GetMapping("/api/cars/new")
    public String createNewCarOfferForm(Model model) {
        Car car = new Car();
        model.addAttribute("car", car);
        return "createNewOfferForm";
    }
    
    @PostMapping("/api/cars")
    public String saveCar(@ModelAttribute("car") Car car, @AuthenticationPrincipal Authentication auth) {
        User customUser = (User)auth;
        car.setOwner(customUser);
        carService.saveCar(car);
        return "redirect:/api/cars";
    }
    
    @GetMapping("/api/cars/view/{id}")
    public String viewOffer(@PathVariable Long id, Model model) {
        model.addAttribute("car", carService.getCarById(id));
        return "viewOffer";
    }
    
     }

用戶物體

@Entity
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String username;
private String password;
private String roles = "ROLE_USER";

@OneToMany(mappedBy = "owner")
private Set<Car> cars = new HashSet<>();

public User() {
    super();
}

public User(String username, String password, String roles) {
    super();
    this.username = username;
    this.password = password;
    this.roles = roles;
//GETTERS SETTERS

汽車物體

@Entity
public class Car {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String carPhotoUrl;
private String carTitle;
private double price;
private int yearModel;
private int mileage;
private String engineType;
private float engineCapacity;
private int enginePower;
private String gearboxType;
private String driveType;
private String colour;
private Boolean isDamaged;

@ManyToOne(cascade = CascadeType.ALL)
@JoinColumn(name="user_id", referencedColumnName = "id")
private User owner;

public Car() {
    super();
}

public Car(String carPhotoUrl, String carTitle, double price, int yearModel, int mileage, String engineType,
        float engineCapacity, int enginePower, String gearboxType, String driveType, String colour,
        Boolean isDamaged) {
    super();
    this.carPhotoUrl = carPhotoUrl;
    this.carTitle = carTitle;
    this.price = price;
    this.yearModel = yearModel;
    this.mileage = mileage;
    this.engineType = engineType;
    this.engineCapacity = engineCapacity;
    this.enginePower = enginePower;
    this.gearboxType = gearboxType;
    this.driveType = driveType;
    this.colour = colour;
    this.isDamaged = isDamaged;
}

 //GETTERS SETTERS

用戶存盤庫

public interface UserRepository extends JpaRepository<User, Long> 
{

Optional<User> findByUsername(String username);

Optional<User> findById(Long id);
}

用戶詳情服務

public class UserDetailsService implements UserDetails{

private String username;
private String password;
private List<GrantedAuthority> authorities;

public UserDetailsService() {
    super();
}

public UserDetailsService(User user){
    this.username=user.getUsername();
    this.password=user.getPassword();
    this.authorities = Arrays.stream(user.getRoles().split(","))
                        .map(SimpleGrantedAuthority::new)
                        .collect(Collectors.toList()); 
}

@Override
public Collection<? extends GrantedAuthority> getAuthorities() {
    return authorities;
}

@Override
public String getPassword() {
    return password;
}

@Override
public String getUsername() {
    return username;
}

@Override
public boolean isAccountNonExpired() {
    return true;
}

@Override
public boolean isAccountNonLocked() {
    return true;
}

@Override
public boolean isCredentialsNonExpired() {
    return true;
}

@Override
public boolean isEnabled() {
    return true;
}

uj5u.com熱心網友回復：

我相信您需要在所有者“cascade=CascadeType.ALL”中提及級聯型別，這實質上意味著用戶（所有者）發生的任何更改也必須級聯到 Car。

如果我們保存一個用戶（所有者），那么所有關聯的汽車也將保存到資料庫中。如果您洗掉用戶（所有者），則與該用戶（所有者）關聯的所有汽車也將被洗掉。夠簡單！

uj5u.com熱心網友回復：

我修好了，但我花了一些時間。現在這是添加汽車的端點（所以沒有@AuthenticationPrincipal）

@PostMapping("/api/cars/addCar")
    public String saveCar(@ModelAttribute("car") Car car, Principal 
    principal) {
        User user = userService.getUserByName(principal.getName());
        car.setOwner(user);
        carService.saveCar(car);
        return "redirect:/api/cars";
    }

我敢打賭這不是一個干凈的解決方案。我已將 UserRepository 的回傳型別從 Optional 更改為 User。我認為這會在未來帶來更多的問題。但現在它有效。

標籤：爪哇 春天 休眠

上一篇：restapiwithspring：基于另一個物體創建一個新物體

下一篇：Spring依賴關系還是默認值？