java - hibernate - 防止获取某些属性

Question

我有一个包含电影列表的导演类和一个包含导演对象的电影类。

问题是每当我获取一部电影时，它也会获取相应的导演，结果，它还会返回该导演执导的电影列表。

我的问题是如何防止每次取电影时都取电影列表？(我仍然想在单独取导演时取电影列表)

这是我的 Director 类:

@Entity
@Table(name = "DIRECTOR")
@JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")
public class Director {

    @Id
    @Column(name = "ID", nullable = false)
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private String id;


    @NotNull
    @Column(name = "D_NAME", nullable = false)
    private String name;

    @NotNull
    @Column(name = "LOCATION", nullable = false)
    private String location;

    @OneToMany(fetch = FetchType.EAGER)
    @JoinColumn(name = "director_id")
    private List<Movie> movies;

    @Column(name = "POSITIONS")
    @Enumerated(EnumType.ORDINAL)
    private Position positions;
    @Column(name = "PHOTO_URL")
    private String photoUrl;

    //setters and getters
}

和一个示例返回的 JSON:

{
  "id": "christopher-nolan",
  "name": "Christopher Nolan",
  "location": "London, England, UK",
  "movies": [
    {
      "id": "inception",
      "title": "Inception",
      "rate": 8.8,
      "numberOfRates": 1470268,
      "categories": "ACTION",
      "director": "christopher-nolan",
      "duration": 123,
      "photoUrl": "http://cdn.persiangig.com/preview/Ku3leEm3N7/MV5BMjAxMzY3NjcxNF5BMl5BanBnXkFtZTcwNTI5OTM0Mw%40%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
      "description": "A thief, who steals corporate secrets through use of dream-sharing technology, is given the inverse task of planting an idea into the mind of a CEO."
    },
    {
      "id": "interstellar",
      "title": "Interstellar",
      "rate": 8.6,
      "numberOfRates": 930496,
      "categories": "ADVENTURE",
      "director": "christopher-nolan",
      "duration": 169,
      "photoUrl": "http://cdn.persiangig.com/preview/tSqxSLMKg5/MV5BMjIxNTU4MzY4MF5BMl5BanBnXkFtZTgwMzM4ODI3MjE%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
      "description": "A team of explorers travel through a wormhole in space in an attempt to ensure humanity's survival."
    },
    {
      "id": "the-dark-knight",
      "title": "The Dark Knight",
      "rate": 9,
      "numberOfRates": 1678434,
      "categories": "ACTION",
      "director": "christopher-nolan",
      "duration": 152,
      "photoUrl": "http://cdn.persiangig.com/preview/SyC1yqkQ55/MV5BMTMxNTMwODM0NF5BMl5BanBnXkFtZTcwODAyMTk2Mw%40%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
      "description": "When the menace known as the Joker wreaks havoc and chaos on the people of Gotham, the caped crusader must come to terms with one of the greatest psychological tests of his ability to fight injustice."
    },
    {
      "id": "the-dark-knight-rises",
      "title": "The Dark Knight Rises",
      "rate": 8.5,
      "numberOfRates": 1146075,
      "categories": "ACTION",
      "director": "christopher-nolan",
      "duration": 164,
      "photoUrl": "http://cdn.persiangig.com/preview/UTo1oyUVDH/MV5BMTk4ODQzNDY3Ml5BMl5BanBnXkFtZTcwODA0NTM4Nw%40%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
      "description": "Eight years after the Joker's reign of anarchy, the Dark Knight, with the help of the enigmatic Selina, is forced from his imposed exile to save Gotham City, now on the edge of total annihilation, from the brutal guerrilla terrorist Bane."
    }
  ],
  "positions": "DIRECTOR",
  "photoUrl": "http://cdn.persiangig.com/preview/xNYollZv1Y/MV5BNjE3NDQyOTYyMV5BMl5BanBnXkFtZTcwODcyODU2Mw%40%40._V1_UY317_CR7%2C0%2C214%2C317_AL_.jpg"
}

和我的电影课:

@Entity
@Table(name = "MOVIE")
public class Movie {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "ID")
    private String id;

    @NotNull
    @Column(name = "TITLE", nullable = false)
    private String title;
    @NotNull
    @Column(name = "RATE", nullable = false)
    private double rate;
    @NotNull
    @Column(name = "NUMBER_OF_RATES", nullable = false)
    private int numberOfRates;
    @Column(name = "CATEGORIES")
    @Enumerated(EnumType.ORDINAL)
    private Category categories;
    @NotNull
    @ManyToOne
    private Director director;
    @NotNull
    @Column(name = "DURATION", nullable = false)
    private int duration;
    @NotNull
    @Column(name = "PHOTO_URL", nullable = false)
    private String photoUrl;
    @Column(name = "DESCRIPTION")
    private String description;

//setters and getters
}

和一个示例返回的 JSON:

{
  "id": "interstellar",
  "title": "Interstellar",
  "rate": 8.6,
  "numberOfRates": 930496,
  "categories": "ADVENTURE",
  "director": {
    "id": "christopher-nolan",
    "name": "Christopher Nolan",
    "location": "London, England, UK",
    "movies": [
      {
        "id": "inception",
        "title": "Inception",
        "rate": 8.8,
        "numberOfRates": 1470268,
        "categories": "ACTION",
        "director": "christopher-nolan",
        "duration": 123,
        "photoUrl": "http://cdn.persiangig.com/preview/Ku3leEm3N7/MV5BMjAxMzY3NjcxNF5BMl5BanBnXkFtZTcwNTI5OTM0Mw%40%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
        "description": "A thief, who steals corporate secrets through use of dream-sharing technology, is given the inverse task of planting an idea into the mind of a CEO."
      },
      {
        "id": "interstellar",
        "title": "Interstellar",
        "rate": 8.6,
        "numberOfRates": 930496,
        "categories": "ADVENTURE",
        "director": "christopher-nolan",
        "duration": 169,
        "photoUrl": "http://cdn.persiangig.com/preview/tSqxSLMKg5/MV5BMjIxNTU4MzY4MF5BMl5BanBnXkFtZTgwMzM4ODI3MjE%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
        "description": "A team of explorers travel through a wormhole in space in an attempt to ensure humanity's survival."
      },
      {
        "id": "the-dark-knight",
        "title": "The Dark Knight",
        "rate": 9,
        "numberOfRates": 1678434,
        "categories": "ACTION",
        "director": "christopher-nolan",
        "duration": 152,
        "photoUrl": "http://cdn.persiangig.com/preview/SyC1yqkQ55/MV5BMTMxNTMwODM0NF5BMl5BanBnXkFtZTcwODAyMTk2Mw%40%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
        "description": "When the menace known as the Joker wreaks havoc and chaos on the people of Gotham, the caped crusader must come to terms with one of the greatest psychological tests of his ability to fight injustice."
      },
      {
        "id": "the-dark-knight-rises",
        "title": "The Dark Knight Rises",
        "rate": 8.5,
        "numberOfRates": 1146075,
        "categories": "ACTION",
        "director": "christopher-nolan",
        "duration": 164,
        "photoUrl": "http://cdn.persiangig.com/preview/UTo1oyUVDH/MV5BMTk4ODQzNDY3Ml5BMl5BanBnXkFtZTcwODA0NTM4Nw%40%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
        "description": "Eight years after the Joker's reign of anarchy, the Dark Knight, with the help of the enigmatic Selina, is forced from his imposed exile to save Gotham City, now on the edge of total annihilation, from the brutal guerrilla terrorist Bane."
      }
    ],
    "positions": "DIRECTOR",
    "photoUrl": "http://cdn.persiangig.com/preview/xNYollZv1Y/MV5BNjE3NDQyOTYyMV5BMl5BanBnXkFtZTcwODcyODU2Mw%40%40._V1_UY317_CR7%2C0%2C214%2C317_AL_.jpg"
  },
  "duration": 169,
  "photoUrl": "http://cdn.persiangig.com/preview/tSqxSLMKg5/MV5BMjIxNTU4MzY4MF5BMl5BanBnXkFtZTgwMzM4ODI3MjE%40._V1_UX182_CR0%2C0%2C182%2C268_AL_.jpg",
  "description": "A team of explorers travel through a wormhole in space in an attempt to ensure humanity's survival."
}

我该如何解决这个问题？

Answer 1

只需将电影的获取类型从 Eager 更改为 Lazy。