Defina在Hibernate 4上的默认类型映射

Question

I need to define/override the default hibernate mapping to solve the problem of the java.util.UUID default mapping.

I've been looking at several comments related to this topic: Here Postgresql UUID supported by Hibernate? and Postgres + Hibernate + Java UUID and Persisting UUID in PostgreSQL using JPA and and Hibernate documentation.

However the easier solution of annotate; something like @Type(type="pg-uuid"), does not works for me since i need to run with different databases (eg H2)

So what i need is to "register org.hibernate.type.PostgresUUIDType as the default Hibernate type mapping for all attributes exposed as java.util.UUID" as has been said in several of the comments.

Sadly after checking the documentation i still don't get exactly how to do it.

Could you, please, explain or point me to a more detailed information about how to override the default type mapping in Hibernate 4.2?

Thanks, and regards,

Answer 1

The best solution i've found is to define a custom type that will switch depending on environmental variables, similar to what is done here:

https://zorq.net/b/2012/04/21/switching-hibernates-uuid-type-mapping-per-database/

So i defined a MyUuid class, annotate the related UUID fields in the entity with @Type(type="whatever") and, at entity level, i defined the new mapping

@TypeDef(name="whatever", defaultForType = UUID.class, typeClass = MyUuid.class)