在Hibernate中使用超类中的@OneToOne注释字段

Question

我有课程Document，其中包含带Ad ad注释的字段@OneToOne。 类ResultDocument扩展Document，应用JOINED继承策略。当我启动我的应用程序时，我收到错误： org.hibernate.MappingException: property [ad] not found on entity [ua.translate.model.ad.ResultDocument]

请解释我这个错误的原因。

班级文件：

@Entity
@Table(name = "INIT_DOCUMENT_TEST")
@Inheritance(strategy = InheritanceType.JOINED)
public class Document {


@Id
@SequenceGenerator(name = "standart",initialValue = 1)
@GeneratedValue(generator = "standart",strategy =GenerationType.SEQUENCE)
@Column(name = "DOCUMENT_ID")
private long id;

@Lob
@Column(name = "DOCUMENT_FILE",nullable = false)
private byte[] file;

@Column(name = "DOCUMENT_FILE_NAME",nullable = false)
private String fileName;

@Column(name = "DOCUMENT_CONTENT_TYPE",nullable = false)
private String contentType;

@OneToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "DOCUMENT_AD_ID")
private Ad ad;
.....
}

class ResultDocument：

@Entity
@Table(name = "RESULT_DOCUMENT_TEST")
@PrimaryKeyJoinColumn(name= "result_document_id")
public class ResultDocument extends Document{

    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "TRANSLATOR",nullable = false)
    private Translator downloader;
    .....
}

Answer 1

我认为您不应该从Document扩展，因为如果您使用的是hibernate或JPA，则该技术使用该关系而不执行继承。