We've decided to move our platform from OJB to Hibernate.

One very useful feature of OJB we made extensive use of was the conversion capability. It enabled you to do things like persist a collection to a clob or blob column.

Example from OJB mapping:


How would I accomplish this in Hibernate? If not built-in, what would be the recommended way we could build it into our Hibernate wrapper classes (i.e. in preStore or something like that)

TIA,

Alex

Hibernate has a much more sophisticated facility for this.

check out UserType and CompositeUserType

Thanks, looks very clean - any repositories of common UserType implementations? (i.e. OJB bundles a number of them)

Re: Does Hibernate have Column Conversion like OJB?

In contrast to OJB using Hibernate's PersistentEnum/UserType introduces unwanted dependency on Hibernate-specific classes. As result my business classes that require custom mapping will depend on Hibernate classes (something that "transparent persistence" OR mapping system should avoid).

Does Hibernate allow to delegate column conversion logic into separate class?






Thanks a lot!
Andy Malakov

Please read how UserType works. This is just wrong.

Thank you very much.

Now I see that my statement only applicable to PersistentEnum.

UserType is a bit heavy for one-field data mappings but will do the job.

All the Best,
Andy