ObjectDB ObjectDB

PostUpdate collection null

#1

Hello,

I have an entity MyEntity with a collection attribute myCollection. I have an EntityListener on MyEntity with a @PostUpdate method. When I try to access myCollection from the PostUpdate method, this collection is null. If I try to access the collection from the PreUpdate method, the collection is populated. The collection is eagerly fetched.

public class MyEntity {

    @OneToMany(fetch=FetchType.EAGER)

    private ArrayList<OtherEntity> myCollection = new ArrayList<OtherEntity>();

}


Thanks,

farid

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#2

It is very difficult to provide help without a test case that demonstrates the problem.

Please look at the following test case:

import java.util.*;

import javax.persistence.*;


public final class T1473
{
    static java.sql.Date myDate;

    public static void main(String[] args) {

        EntityManagerFactory emf =
            Persistence.createEntityManagerFactory(
                "objectdb:$objectdb/db/test.tmp;drop");

        EntityManager em = emf.createEntityManager();
        em.getTransaction().begin();
        MyEntity e = new MyEntity(1);
        e.myCollection.add(new MyEntity(2));
        e.myCollection.add(new MyEntity(3));
        em.persist(e);
        em.getTransaction().commit();
        em.close();

        em = emf.createEntityManager();
        e = em.find(MyEntity.class, 1);
        em.getTransaction().begin();
        e.myCollection.add(new MyEntity(4));
        em.getTransaction().commit();

        em.close();
        emf.close();
    }

    @Entity
    public static class MyEntity {
        @Id int id;
       
        @OneToMany(fetch=FetchType.EAGER, cascade=CascadeType.PERSIST)
        List<MyEntity> myCollection = new ArrayList<MyEntity>();
       
        MyEntity(int id) {
            this.id = id;
        }
       
        @PostUpdate
        public void postUpdate() {
            System.out.println(myCollection.size());
        }
    }
}

The postUpdate method is invoked as expected and the output is 3.

You may try to modify this test in order the demonstrate the issue that you have.

ObjectDB Support
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