Question

我有4个实体：Play，Actor，Play-representation和Category。每个游戏都属于一个类别，并且游戏表现将游戏与剧院和一些演员在给定时间相关联。以下是实体：

@Entity
@Table(name = "category")
public class Category {

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

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

    @OneToMany(mappedBy="category")
    private List<Play> playList = new ArrayList<Play>();

@Entity
@Table(name = "actor")
public class Actor {

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

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

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

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

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

    @ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinTable(name = "play_representation_category",
            joinColumns = {@JoinColumn(name = "actor_id")},
            inverseJoinColumns = {@JoinColumn(name = "play_representation_id")})
    private Set<PlayRepresentation> playRepresentations = new HashSet<>(0);

@Entity
@Table(name = "play")
public class Play {

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

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

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

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

    @NotNull
    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    private Category category;

@Entity
@Table(name = "play_representation")
public class PlayRepresentation {

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

    @OneToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = "play_id")
    private Play play;

    @OneToOne
    @JoinColumn(name = "theater_id")
    private Theater theater;

    @Column(name = "date")
    private Timestamp airingDate;

    @ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinTable(name = "play_representation_category",
            joinColumns = {@JoinColumn(name = "play_representation_id", nullable=false)},
            inverseJoinColumns = {@JoinColumn(name = "actor_id", nullable=false)})
    private Set<Actor> actors = new HashSet<>(0);

我遇到的问题是hibernate试图找到play_representation和类别之间的关系！我一直试图坚持这种戏剧的关系，但似乎我弄错了，无法弄清楚最好的方法......顺便说一句，这是一个postgresql数据库。

我还在学习，所以如果您对我分享的代码有任何其他提示，请告诉我们！

编辑：错误是：

org.postgresql.util.PSQLException: ERROR: relation "play_representation_category" does not exist
  Position: 281

Answer 1

我不需要mappedBy，它实际上是一个错字 - 我写了play_representation_category而不是play_representation_actors。非常愚蠢，对吧？至少我终于找到了它：）

Hibernate不是持久的嵌套关系

1 个答案: