Hello!

I am using Hibernate Annotations 3.3.0 GA and Hibernate Core 3.2.5.GA with a MySQL 5 database.
One of my object attributes is annotated with

@Column(nullable = false, unique = true)
public String getPath() { ... }

and the MySQL table definition accordingly says

UNIQUE KEY `path` (`path`)

When I try to persist an object with an existing value for 'path' I get a ConstraintViolation, which is the correct and expected behavior.
I wonder, however, why I get a org.hibernate.exception.ConstraintViolationException instead of a javax.persistence.EntityExistsException.

My application consistently uses the EJB3 persistence API and no Hibernate-specific API calls. Why is a Hibernate exception thrown in an EJB3-only environment?

Thank you and best regards, Uwe

The exception is thrown because Hibernate is your EJB3 persistence provider. These are Runtime Exceptions so they dont have to be declared. The above behaviour is absolutely fine in my opinion.

So how can I detect a constraint violation when using Hibernate's EJB3 implementation without having to use Hibernate-specific classes, i.e. without catching Hibernate-specific exceptions?
In other words, how can I detect a constraint violation without using any vendor-specific code but only plain EJB3-compatible code?