JPA继承无法确定类型

Question

我有一个简单的JPA映射,但我不断得到一个Could not determine type for例外.设置器和getter被省略.

@Entity
@Inheritance(strategy = InheritanceType.JOINED)
public class SupervisionCommand {

    @Id
    @GeneratedValue
    protected Long id;

}

@Entity
public class MySupervisionCommand extends SupervisionCommand {

}

@Entity
public class Job {

    @Id
    @GeneratedValue
    private Long id;

    private SupervisionCommand command;

}

完整的异常消息: Could not determine type for: com.family.model.SupervisionCommand, at table: job, for columns: [org.hibernate.mapping.Column(command)]

Answer 1

您需要在命令上使用OneToOne或ManyToOne注释(取决于实际的基数):

@ManyToOne
private SupervisionCommand command;

字段的默认映射是@Column.并且Hibernate不知道使用哪种类型的列(varchar？number？)来存储SuperVisionCommand实例.如果它实现了Serializable,Hibernate会将它序列化并将其存储在BLOB列中,但这不是你想要的.