Hibernate不是坚持嵌套关系
我有4个实体:播放,演员,播放表示和类别。 每场比赛属于一个类别,并且在某个特定时间,比赛将比赛与剧院和一些演员相关联。 下面是实体:Hibernate不是坚持嵌套关系
@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是试图找到play_representation和类别之间的关系!我一直试图坚持关系的戏剧,但它似乎我得到了错误,无法找出最好的办法做到这一点...这是一个postgresql数据库顺便说一句。
我还在学习,所以如果您有关于我分享的代码的任何其他提示,请让我知道!
编辑:错误是:
org.postgresql.util.PSQLException: ERROR: relation "play_representation_category" does not exist
Position: 281
我并不需要的mappedBy,它实际上是一个错字 - 我写play_representation_category代替play_representation_actors的。很愚蠢,是吧?至少我终于找到了:)
那么你确实需要一个mappedBy,如果这个关系是双向的。否则,它是两个独立的关系,你会在以后得到问题 –
好吧,我会检查出来的!谢谢! –
和错误信息是?! –
你的ManyToMany是双向的,但你还没有把'mappedBy'链接到它们 –