Native ID and custom types

PawelMiniewicz · **Joined:** Mon Dec 05, 2005 8:13 am **Posts:** 9

Hi,
I'm using Hibernate 3.1rc2.
In my application i'm using a wrapper class for the primary key of every entity, e.g.

Code:

@Entity
public class ProductEJB implements Serializable {
...
@Column(name = "id")
@Id( generate = GeneratorType.AUTO)
@Type( type="EntityId")
public ProductId getId() 

Class ProductId is a simple type safe wrapper for Integer and I want it to be generated natively by the database. I created apropriate custom Hibernate type, but it didn't work because of an assert in org.hibernate.id.IdentifierGeneratorFactory: ( getReturnedClass() in my case returned ProductId)

Code:

public static Serializable get(ResultSet rs, Type type) 
   throws SQLException, IdentifierGenerationException {
   
      Class clazz = type.getReturnedClass();
      if ( clazz==Long.class ) {
         return new Long( rs.getLong(1) );
      }
   ...
      else {
         throw new IdentifierGenerationException("this id generator generates long, integer, short or string");
      }
      
   }

I also tried to extend post insert generator class from Hibernate, but in the end the same static member from IdentifierGeneratorFactory was called.

The only solution I found was to patch Hibernate source, so I added to org.hibernate.type:

Code:

public interface AutoGeneratedIdType {
   public Serializable getGeneratedId( ResultSet rs) throws SQLException;
}

and changed IdentifierGeneratorFactory:

Code:

...
else if ( type instanceof AutoGeneratedIdType) {
         return ((AutoGeneratedIdType)type).getGeneratedId( rs);
      }
...

Is there a better solution to my problem?

cheers, Pawel

emmanuel · **Posted:** Tue Dec 06, 2005 5:47 pm

use a @GenericGenerator

PawelMiniewicz · **Joined:** Mon Dec 05, 2005 8:13 am **Posts:** 9

This is what I tried to do in the beggining, I extended your IdentityGenerator class, overriden the getResult method and annotated my type with @GenericGenerator of this class. But in AbstractEntityPersister (line: 1969) this code is called

Code:

return IdentifierGeneratorFactory.getGeneratedIdentity( 
                     GetGeneratedKeysHelper.getGeneratedKey(insert), 
                     getIdentifierType() 
               );

that results in calling static getGeneratedIdentity method with the behaviour I have described in my first message. So my generator is never called after the insert to database and IdentifierGenerationException is thrown.

emmanuel · **Posted:** Sat Dec 10, 2005 1:53 pm

@Id(generator="myGen")
@GenericGenerator(name="myGen", ...)

PawelMiniewicz · **Joined:** Mon Dec 05, 2005 8:13 am **Posts:** 9

Emmanuel,
My entity is annotated correctly, just like you show above. And of course generate method of my generator is called. But when this method returns IdentifierGeneratorFactory.POST_INSERT_INDICATOR constant - generator is never called again. After AbstractEntityPersister does insert to the DB, the IdentifierGeneratorFactory is called, which can only handle int, long etc. so exception is thrown.

Pawel