Problem when save object, I have double object ?

Louevie · **Joined:** Wed Jan 28, 2009 10:16 am **Posts:** 37

Hello,

Here is my problem :
I have an object that I save using Hibernate.
I create another object and inject the same data (id, etc... I annoted my id to
@Id
@GeneratedValue(strategy = GenerationType.AUTO)

I do not know if this replae the id that I specifiy when I create the new object ?

But the fact is that I override the equals method like this :
@Override
public boolean equals(Object obj) {
if (obj instanceof Dossier) {
Dossier obDossier = (Dossier)obj;
return getId().equals(obDossier.getId());
}
return false;
}

And it appears that when I save another object is created. How can I do to say that this two instance are the same to save one time in data base ?

mmerder · **Posted:** Tue Feb 24, 2009 7:36 am

Can you post your example code?

Hibernate uses the Id to see if an object is new (transient) or just detached. So if you copy your object including the id-value, a merge() will result in an update of the "old" object's database-row.

littypreethkr · **Posted:** Tue Feb 24, 2009 7:38 am

Second time instead of save call saveOrUpdate

Louevie · **Joined:** Wed Jan 28, 2009 10:16 am **Posts:** 37

In fact, I do not understand :

I have my object, for example : Dossier
I have a model interface IDossier :
I have a implementation of this interface : DossierImpl

DossierImpl is like this :

DossierImpl implements IDossier {
...
private Dossier dossier;
...

And I update dossier data using my DossierImpl object.

I used this in the MVC context with a graphic interface.

So when I save my object, I used the interface method save();

IDossier dossier = new DossierImpl();
dossier.save();

And this method is like this :
Session session = HibernateUtil.getSession();
Transaction transaction = session.beginTransaction();
session.saveOrUpdate(dossier);
transaction.commit();
session.close();

When I exit and exucute again my application, I get my Dossier object and I inject it into a IDossier model :

public static IDossier createDossier(Dossier dossier) {
IDossier dosBean = new DossierImpl();
And I used the setter to put the same data that this dossier to the DossierImpl. So I have one dossier (argument) and another in DossierImpl().

In fact, I maybe I just need to create a DossierImpl(Dossier dossier) constructor...?

mmerder · **Posted:** Tue Feb 24, 2009 7:51 am

I do not really understand your problem, I guess. Do you mean you have a problem, because you have two different Java-objects, and want them to be the same ("==" should be true)? If yes, why?

Louevie · **Joined:** Wed Jan 28, 2009 10:16 am **Posts:** 37

The method equals is not called... ? I put a log in and it never pass in.
And hibernate use when I save.
select nextval ('hibernate_sequence')

littypreethkr · **Posted:** Tue Feb 24, 2009 8:33 am

Louevie wrote:

When I exit and exucute again my application, I get my Dossier object and I inject it into a IDossier model

Can you post the code which gets and inject the Dossier object?

Louevie · **Joined:** Wed Jan 28, 2009 10:16 am **Posts:** 37

Ok this is my code...

A method to translate...

Code:

// This class aims all the method to transform a IObject to Object or the // reverse
public class BeanFactoryFromModel {
public static IDossier createDossier(Dossier dossier) {
      IDossier dosBean = new DossierImpl(enumTypeVehicule);
      if (null != dossier) {
         dosBean.setId(dossier.getId());         
      }
      
      return dosBean;
   }
}

public class DossierImpl implements IDossier {
   
   private Dossier dossier;
   
   
   public DossierImpl() {
      dossier = new Dossier();
   }

   public DossierImpl(IDossier dossier) {
      this.dossier = BeanFactoryFromModel.createDossier(dossier);
   }


   @Override
   public int getId() {
      return dossier.getId();
   }

        public void save() {
      System.out.println("Save Dossier");
      Session session = HibernateUtil.getSession();
      Transaction transaction = session.beginTransaction();
      session.saveOrUpdate(dossier);
      transaction.commit();
      session.close();
   }
...
}


public interface IDossier l {
        public void save();
   public int getId();
        public void setId(int id);
}

// This is the method called when I want to create a IDossier
public class Util {
public static IDossier createDossierVehiculeAgricole () {
      IDossier dossier = new DossierImpl();
      saveDossier(dossier);
      createAllDirectoryForDossier(dossier);
      return dossier;
   }
...
}

[/code]

littypreethkr · **Posted:** Tue Feb 24, 2009 12:17 pm

Here I am a bit confused nw.

public static IDossier createDossier(Dossier dossier) { ... }

public DossierImpl(IDossier dossier) {
this.dossier = BeanFactoryFromModel.createDossier(dossier);
}

So Dossier also implements IDossier ?
I thot Dossier is ur entity class.

Can u give the exact code which causes the creation of a new object where you expect update?

Louevie · **Joined:** Wed Jan 28, 2009 10:16 am **Posts:** 37

In fact, no. I have a IDossier that is an interface for my model (MVC).
DossierImpl is the implementation that contains my Dossier object that is related to Hibernate :

Code:

@Entity
public class Dossier implements Serializable {
...

   @CollectionOfElements
   @JoinTable(name = "dossier_document_join", joinColumns = @JoinColumn(name = "file"))   
   @Cascade(value = CascadeType.ALL)
   private List<Document> documents;

....

littypreethkr · **Posted:** Wed Feb 25, 2009 12:32 am

Then what about this code?

Code:

public static IDossier createDossier(Dossier dossier) { ... }

public DossierImpl(IDossier dossier) {
this.dossier = BeanFactoryFromModel.createDossier(dossier);
}

Is it that the BeanFactoryFromModel has an overloaded createDossier method?

Also plz give the exact code which causes the creation of a new object where you expect update?