CGLIBLazyInitializer (Proxy) ignores final property methods

Pvblivs · **Joined:** Wed Jan 05, 2005 6:54 am **Posts:** 15

Hi,

Imagine the following class (in Hibernate3 3.1).

Code:

public abstract class LabelledEntity {

  private String label;

  public final String getLabel() {
    return label;
  }

  public final void setLabel(String label) {
    this.label = label;
  }

}

You can "finalize" methods to ensure that an implementing class does not override them.

I found out that, in a many-to-one association referring to implementors of LabelledEntity, accesses to the "Label" property of a many-to-one referred object are not intercepted by the CGLIBLazyInitializer. This is a bit ugly: one may wonder why his "label" is always null even if it has some label value in the database.

Deleting the "final" decoration of the label property is removing this issue.

Just wanted to share my new knowledge. :-)

Regards,

Stefan Schubert

baliukas · **Posted:** Mon Dec 05, 2005 5:44 am

"You can "finalize" methods to ensure that an implementing class does not override them"
Proxy overrides methods for interception and final methods can not intercepted ( you ensure that a proxy class does not override and intercept them ).

Pvblivs · **Joined:** Wed Jan 05, 2005 6:54 am **Posts:** 15

baliukas wrote:

Proxy overrides methods for interception and final methods can not intercepted ( you ensure that a proxy class does not override and intercept them ).

This is quite important, isn't it? For developers who are not familiar with Hibernate architecture details it is worth to be added to the documentation that POJOS should never contain any final property accessors if they want those methods to be used by Hibernate.
Even better would be if Hibernate checked for the final marker in accessors on creation of the session factory as Hibernate is knowing exactly whether it uses the proxies or not and therefore it knows the contract it needs to make with the developer (e.g. "don't you use final").

Thanks for your answer!

Stefan Schubert

axismundi · **Joined:** Mon Aug 22, 2005 5:45 am **Posts:** 146

Pvblivs wrote:

baliukas wrote:

Proxy overrides methods for interception and final methods can not intercepted ( you ensure that a proxy class does not override and intercept them ).

This is quite important, isn't it? For developers who are not familiar with Hibernate architecture details it is worth to be added to the documentation that POJOS should never contain any final property accessors if they want those methods to be used by Hibernate.
Even better would be if Hibernate checked for the final marker in accessors on creation of the session factory as Hibernate is knowing exactly whether it uses the proxies or not and therefore it knows the contract it needs to make with the developer (e.g. "don't you use final").

Hibernate 3.1 does check the accessor signature.

max · **Posted:** Mon Dec 05, 2005 6:04 am

As all things important it is already in the docs:

http://www.hibernate.org/hib_docs/v3/re ... pojo-final

and i also think that hibernate logs a warning if there is final methods.

Anything else ? ;)