@MappedSuperclass ：持久化实体应该有主键

Question

I'm working with Spring Data JPA and I'm trying to create 4 different entities that will have exactly the same fields but they will be stored in 4 different tables.

This is my key class

public class IndexId implements Serializable {

    private int seqNo;
    private String index;

    // getters and setters
}

Then I have the base class:

@MappedSuperclass
public class BaseIndex {

    @Id
    @Column(name = "seq_no", nullable = false)
    protected int seqNo;

    @Id
    @Column(name = "index", nullable = false)
    protected String index;

    @Column(name = "value", nullable = false)
    protected String value;

    //getters/setters
}

Then my entity that will store in the database:

@Entity
@IdClass(IndexId.class)
@Table(name = "bibliographic_single_index")
public class BibliographicSingleIndex extends BaseIndex implements Serializable { }

This is the error I get: Persistent entity 'BibliographicSingleIndex' should have primary key . I also tried with the properties declared as private and the articles I see on this subject seem to do the same thing.

With these pieces of code is it possible to identify what I'm doing wrong?

Answer 1

I believe every entity needs a separate java class for the id class. You wouldn't have the problem with embedded ids I think.