Can I create a validator from an already existing annotation

javierpaniza · **Posted:** Mon Jun 18, 2007 10:50 am

Hi,

I want to write something like this:

Code:

@Column(length=40, nullable=false)
private String name;

instead of this:

Code:

@Length(max=40) @NotNull
@Column(length=40, nullable=false)
private String name;

That is, I want that Hibernate validator validates from a JPA annotation, or
from whatever annotation although I cannot change the source code of it.

Is this possible ?

Thank you in advance

emmanuel · **Posted:** Mon Jun 18, 2007 11:08 am

javierpaniza · **Posted:** Mon Jun 18, 2007 11:41 am

Hi Emmanuel,

why not in addition of ...

Code:

@ValidatorClass(ColumnValidator.class) 
@Target(METHOD) 
@Retention(RUNTIME) 
@Documented public 
@interface Column { 
...
}

for linking annotation to the validator class, we add the option:

validators.xml:

Code:

<validator annotation="javax.persistence.Column" class="mypackage.ColumnValidator"/>

Or, if you hate XML, something like this:

Code:

@AnnotationToValidate(javax.persistence.Column.class)
public class CapitalizedValidator implements PropertyConstraint {

  public boolean isValid(Object value) {
  ...
  }

}

What do you think ?

emmanuel · **Posted:** Mon Jun 18, 2007 6:43 pm

The idea is interesting, but really the JPA provider should consume the data from Validator. This is how we intend it in JSR-303. Several annotations expressing the same constraint will fragment things more than helping.

emmanuel · **Posted:** Mon Jun 18, 2007 6:43 pm

The idea is interesting, but really the JPA provider should consume the data from Validator. This is how we intend it in JSR-303. Several annotations expressing the same constraint will fragment things more than helping.

javierpaniza · **Posted:** Tue Jun 19, 2007 5:53 am

emmanuel wrote:

the JPA provider should consume the data from Validator.

It's an option. But ALL JPA implementations will need to understand Hibernate validator.

emmanuel wrote:

This is how we intend it in JSR-303.

This is good news, at least for me.

Thanks

leopinho · **Joined:** Sun Sep 30, 2007 2:58 pm **Posts:** 26

More informations at:
http://opensource.atlassian.com/projects/hibernate/browse/HV-43

Regards,
Leonardo