I'm using Hibernate Validator to validate form submissions; currently, however, validation is not taking place. I've annotated certain properties with @NotEmpty, and even though I submit an empty form (all blank) the validator returns 0 violations. Any one know what is causing this malfunction? Below is my code:

Spring DI --


Data Transfer Object with validation annotations --


Controller --

Registration is an instance of RegistrationDto? Is there anything in the log file? Turn on debug level log for org.hibernate.validator and check if this gives any hints on what's going on.

--Hardy

Yes, registration is an instance of RegistrationDto.

I turned on debug level logging and the following is what was returned:
Do you see what's wrong?

The log shows that the validator framework properly bootstraps.
Are you sure that the fields you are validating don't have any whitespaces or something? @NotEmpty is not trimming the string.

My app is grails based with chunks of pure java ( I don't know if that makes a difference, but I thought it best to share that fact).

In any event, I reloaded my (ivy2) dependency cache, and in doing so I got the following error message:
I'm confused as to why I'm getting this error. I checked my dependency report, and hibernate-validator pulls in jpa-api by org.hibernate.java-persistence (Revision: 2.0.Beta-20090815) As I understand it, the problem is when you have a missing or incomplete JPA 2.0 in the classpath.

Also it seems the way to resolve this is to "bootstrap Bean Validation with a custom TraversableResolver... use DefaultTraversableResolver just without the JPA checking code." (viewtopic.php?p=2422807)

Is my understanding of the problem correct? Are there any alternative resolutions? How would you recommend I proceed? Thanks.

Hibernate Validator itself does not depend on JPA 2. It is an optional dependency. Validator will check at runtime whether the JPA dependencies are on the classpath. If so it will delegate to a JPATraversableResolver.
Which version of Validator are you using, btw? The current version of the JPA dependency is org.hibernate.javax.persistence:hibernate-jpa-2.0-api:1.0.0.Final. That's why I'm asking. I recommend you upgrade to Validator 4.1.0.Final.
And yes, you can force a specific TraversableResolver during bootstrapping.

I was using 4.0.2.GA (that was the latest version in the jboss maven2 repo). As you suggested I upgraded to 4.1.0.Final. Unfortunately, however, I continue to get:
I even added org.hibernate.javax.persistence:hibernate-jpa-2.0-api:1.0.0.Final to my dependency list, but that didn't solve the error either.

Any other suggestions on what could be causing the error & how to resolve it? Does the getPersistenceUtil() error mean I have to implement a custom TraversableResolver?

Hi,

Interesting, which jpa api version does get included now? org.hibernate.javax.persistence:hibernate-jpa-2.0-api:1.0.0.Final?
To solve your problem regarding the traversable resolvers - you have several options:

• JPA is an optional dependency for Validator. If you are not using JPA find out where and why the JPA dependency gets included and remove/exclude it.
• As you mentioned earlier, the error indicates a incomplete JPA 2 implementation. Hibernate Validator checks for javax.persistence.PersistenceUtil on the classpath. If this class is on the classpath it assumes JPA 2 is available and instantiates a JPATraversableResolver. This resolver in turn will call Persistence.getPersistenceUtil().isLoaded(). If javax.persistence.PersistenceUtil is on the classpath, but Persistence.getPersistenceUtil() does not exist you are having a old/incomplete version of the JPA 2 on the classpath. Make sure you are using the right JPA 2 version if you want to use JPA.
• You can implement a custom TraversableResolver and avoid the problem altogether, but somehow you are covering up some dependency resolving issues which seem to exist in your setup. Implementing a TraversableResolver is btw very easy. Just return true in both of the methods you have to implement.

--Hardy

The current jpa version that is included is: org.hibernate.javax.persistence:hibernate-jpa-2.0-api:1.0.0.Final

I ensured that persistence-api was NOT in the classpath, but the error (see below) continued



I was able to solve the problem by excluding hibernate-jpa from the build. However, I'm confused about the following:

• Why did the error continue in spite of there being (only) hibernate-jpa in the classpath?
• What is the difference between JPATraversableResolver and any other TraversableResolver?

Thanks

-Dan

I can this only happen if you have only the jpa api on the classpath, but no implementation. But maybe this is exactly what you have, since you don't seem to need JPA.



For the first question see above. Regarding the second, TraversableResolver is not a concrete class, but an interface. There is however something like a default implementation if the interface which will for both methods of the interface (isReachable and isCascadable) will just always return true. The idea is that in the case of JPA and lazy loaded association you want to avoid loading lazy data from the database in order to validate it. If it is already persistent in the database it should already have been validated and there is no need to retrieve and validate it again. Have a look at the Bean Validation specification if you want to know more.

--Hardy

Aha! I mis-interpreted the docs and thought that ONLY the jpa api was needed.
Thanks for the explanation; it cleared up my understanding.