How override getter of id column in jpa configuration

Question

I have a problem for @Id in JPA that is described as follow? There is a generic class as follow?

    @MappedSuperclass
    public abstract class BaseEntity<T> implements Serializable {

        private static final long serialVersionUID = 4295229462159851306L;

        private T id;
        public T getId() {
          return id;
        }
        public void setId(T id) {
           this.id = id;
        }

    }

There is another class that extends from it as follow?

@Entity
@Table(name = "DOC_CHANGE_CODE" )
 public class ChangeCode extends BaseEntity<Long> {

     @Id
     @GeneratedValue(generator = "sequence_db", strategy = GenerationType.SEQUENCE)
     @SequenceGenerator(name = "sequence_db", sequenceName = "SEQ_DOC_CHANGE_CODE", allocationSize = 1)     
     public Long getId () {
       return super.getId();
     }
}

Because any sub class has its own sequence, I must specific any subclass @Id, because of that I override the its getter and put some annotations in top of that. Unfortunately it does not work correctly. How do I fix problem and get my goal?

"_Unfortunately it does not work correctly_" Can you be more specific ? — AxelH, Nov 30 '17 at 07:09
As i has explained, any table has its own sequence. I want to assign those sequence to its table instead of @Generator. — reza ramezani matin, Nov 30 '17 at 07:12
try using `return this.getId()` instead of `return super.getId()` — Mehraj Malik, Nov 30 '17 at 07:20

score 0 · Answer 1 · answered Nov 30 '17 at 07:10

0

Try this:

@Entity
@Table(name = "DOC_CHANGE_CODE" )
@SequenceGenerator(name = "sequence_db", sequenceName = "SEQ_DOC_CHANGE_CODE", allocationSize = 1)     
@AttributeOverride(name = "id", column = @Column(name = "ID"))
public class ChangeCode extends BaseEntity<Long> {

    @Override
    @Id
    @GeneratedValue(generator = "sequence_db", strategy = GenerationType.SEQUENCE)
    public Long getId() {
        return id;
    }
}

answered Nov 30 '17 at 07:10

Gal Shaboodi

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Are you sure that it works correctly? – reza ramezani matin Nov 30 '17 at 07:13
just found this (almost exactly same question) : https://stackoverflow.com/questions/5257921/hibernate-how-override-an-attribute-from-mapped-super-class – Gal Shaboodi Nov 30 '17 at 07:30
Your answer does not work – reza ramezani matin Nov 30 '17 at 10:09

Vlad Mihalcea · Answer 2 · 2018-01-06T10:38:52.080

0

It's not possible to override the @Id from a base class.

The only way to do it is to provide your own custom IentifierGenerator and provide a different logic based on the subclass (e.g. using a sequence name based on the subclass name).

That's why adding the @Id attribute in the @MappedSuperclass only makes sense for the assigned generator or for IDENTITY.

edited Jan 06 '18 at 10:38

answered Nov 30 '17 at 08:07

Vlad Mihalcea

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I remove @MappedSuperclass from Generic class and override getter of any filed that i want to be in my entity.It works. Is it correct solution? – reza ramezani matin Nov 30 '17 at 10:15
If you removed `@MappedSuperclass`, no property will be inherited, so of course, it works. However, there is no reason why you should keep the base class anymore. – Vlad Mihalcea Nov 30 '17 at 10:57
@VladMihalcea why this is work ? https://stackoverflow.com/questions/8589928/mappedsuperclass-change-sequencegenerator-in-subclass – ali akbar azizkhani Dec 04 '17 at 16:14

How override getter of id column in jpa configuration

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