Java 类在添加到集合时不持久化新的关联对象

我正在制作一个餐厅管理应用程序，但我在坚持用户关联方面遇到了问题。对于Chef类，有一组与Dish类的关联，以便特定的菜肴可以与特定的厨师关联

我创建了一个将菜肴与厨师关联的方法，当我尝试在我的REST客户端上调用它时，该方法似乎有效，它返回一个带有更新信息的厨师对象的JSON，但是当我调用get chef方法时，JSON不再显示添加的菜肴项

这是chef类以及与Dish对象相关的所有内容

@Table(name="chef")
public class Chef {

    //Chef Attributes
    @Id private String username;
    private String firstName;
    private String lastName;
    private String email;
    private String password;
    private String address;
    private String bio;
    private Boolean delivery;
    private String photoURL;


    // @OneToOne
    // private ChefMenu menu;


    @Transient
    @OneToMany(mappedBy = "chef", cascade = CascadeType.ALL)
    @JsonIgnoreProperties("chef")
    private Set<Dish> menuItems;

    public Set<Dish> getMenuItems() {
        if (this.menuItems == null) {
            this.menuItems = new HashSet<Dish>();
        }
        return this.menuItems;
    }

以下是用于从存储库向厨师添加新菜的方法

@Transactional
    public Chef addDishToMenu(Chef c, Dish d) {
        c.addDish(d);
        entityManager.merge(c);
        return c;
    }

最后是控制器类的代码：

@PostMapping("dish/create/{dishName}/{cuisine}/{price}/{maxQuantity}/{dietaryRestriction}/{mealIngredients}/{cookingTime}")
    public ResponseEntity createDish(String username,
            @PathVariable("dishName") String dishName, @PathVariable("cuisine") String cuisine,
            @PathVariable("price") String price, @PathVariable("maxQuantity") String maxQuantity,
            @PathVariable("dietaryRestriction") String dietaryRestriction,
            @PathVariable("mealIngredients") String mealIngredients, @PathVariable("cookingTime") String cookingTime)
           {
        Dish d = new Dish();
        Double p = Double.parseDouble(price);
        //int mQ = Integer.parseInt(maxQuantity);

            try {
            d = foodRepository.createDish(dishName, cuisine, p, maxQuantity, dietaryRestriction,
                    mealIngredients, cookingTime);
        } catch (InvalidInputException e) {
            return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(new Response(false, e.getMessage()));
        }

            return ResponseEntity.status(HttpStatus.OK).body(d);

     }



@PostMapping("dish/add/{username}/{dishName}")
     public ResponseEntity addDishToMenu(@PathVariable("username") String username, @PathVariable("dishName") String dishName) throws NullObjectException {
         Chef c = new Chef();
         Dish d = new Dish();
         c= chefRepository.getChef(username);
         d = foodRepository.getSpecificDish(dishName);
         c = foodRepository.addDishToMenu(c, d);
         return ResponseEntity.status(HttpStatus.OK).body(c);
     }

 @GetMapping("/get/{username}")
    public ResponseEntity getChef(@PathVariable("username") String username) {
        // List<AppUser> user;
        Chef chef = new Chef();
        try {
            chef = chefRepository.getChef(username);
            // user = userRepository.getAppUserQuery(username);
        } catch (NullObjectException e) {
            return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(new Response(false, e.getMessage()));
        }
        return ResponseEntity.status(HttpStatus.OK).body(chef);// user.get(0));

    }

但是，当我使用getChef REST调用时，我得到以下信息：

{
"username": "Favreau4",
"firstName": "Jon",
"lastName": "Favreau",
"email": "chefFavreau@email.com",
"password": "j+9UECq/PLA=$I+HsXngf/b82+rMtPQQO",
"address": null,
"bio": null,
"delivery": null,
"photoURL": null,
"menuItems": [],
"order": [],
}

---

有人知道如何解决这个问题吗？

您知道@Transient annotation吗？瞬态用于将变量标记为不可预测。因此，您的菜单项没有得到持久化或保存在数据库中。

是的，谢谢，我去掉了临时注释，它开始出现，我想我对@transient注释的作用有错误的想法。非常感谢。

{
"username": "Favreau4",
"firstName": "Jon",
"lastName": "Favreau",
"email": "chefFavreau@email.com",
"password": "j+9UECq/PLA=$I+HsXngf/b82+rMtPQQO",
"address": null,
"bio": null,
"delivery": null,
"photoURL": null,
"menuItems": [
  {
"dishName": "Big sandwich",
"cuisine": "american",
"price": 5,
"maxQuantity": "3",
"dietaryRestriction": "bacon",
"mealIngredients": "bacon,lettuce,tomato,bread",
"cookingTime": "10mins"
}
],
"order": [],
}

{
"username": "Favreau4",
"firstName": "Jon",
"lastName": "Favreau",
"email": "chefFavreau@email.com",
"password": "j+9UECq/PLA=$I+HsXngf/b82+rMtPQQO",
"address": null,
"bio": null,
"delivery": null,
"photoURL": null,
"menuItems": [],
"order": [],
}