java - 没有为实体指定标识符 : content. ContentType

Question

我有两个表，Content 和 ContentType

每个内容都有一种内容类型

每种内容类型可能包含在许多内容中。

这是我的模型:

@Entity
@Table(name = "content")
public class Content implements Serializable {

public Content() {}

@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE)
private long id;

@ManyToOne
private ContentType contentType;

@NotNull
private String title;

//getter/setters }

ContentType 类:

@Entity
@Table(name = "contentType")
public class ContentType implements Serializable {

    public ContentType() {  }

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
    private long id;

    @NotNull
    private String type;

    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "content")
    private Set<Content> content;
//getter/setters }

但是我得到了这个异常:

No identifier specified for entity: content.ContentType

Answer 1

尝试进行以下更改。

mappedBy 应指向 Content 类中 ContentType 对象的名称。

@OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "contentType")
private Set<Content> content;

希望这有帮助。