Hi,

Would it be a good or bad idea to create a org.hibernate.validator.annotation.BusinessKey annotation?

The goal is create a mean to use Entities in hash-based classes no matter the Entity is transient, detached or persistent.

So the use case: I have an "normal" entity with @Id, @OneToMany aso.

I add..

@BusinessKey
String email;

...to the email and possibly to several other fields. And then:

1) A unique constraint will be added in the DDL for those properties forming the business key

2) @PrePersist and @PreUpdate will verify the the business key is set

3) If build-time bytecode instrumentation has been used, the equals and hashcode methods will be enhanced to use the business key in the comparison.

Then, hopefully, I'd be able to use my entities in any hash-based collection regardless of the state? Or is there a more clever way to achieve this declaratively?

br,
Jens

that sounds nice, though I don't like part 3.

Hi jensaug,

It's funny that you're mentioning this @BusinessKey annotation, I've just implemented something like this yesterday. It allows you to declare a business key for an object using a @BusinessObject annotation.
Then you can declare in the annotation if the business key inherits from the parent class (or interfaces) in the case you have inheritance.

It works like a charm except for entities having all fields nullable (except the ID). In that case I've no other way than using a business key containing the ID of the entity.

This annotation can then be used with an AnnotatedBusinessObject class that read the business key from the @BusinessObject annotation and then redefine the hashCode() and equals() methods to use that business key.

If you're interested I can compile a tar file containing the source (I don't have an open source project for this).


Cheers,
/Benoit