Continue after Exception was thrown??

steggo · **Joined:** Mon Apr 22, 2013 4:53 am **Posts:** 2

Hi all,

I'm facing the problem that my custom DAO object (derived from HibernateDaoSupport) breaks after a DataIntegrityViolationException was thrown.

I've a MySQL table with 2 different unique keys (email and username must be unique in that table). When I'm trying to insert a new entity in that table and one of the attributes violates an unique key constraint, a DataIntegrityViolationException is thrown. After that exception I like to figure out what was the reason (either a duplicated key on column "username" or "email" or on both columns), but my HibernateDaoSupport object seems to be broken then:

I'm using Hibernate 3.1.3 on a multitheaded spring-based webservice. I assume that the session handling is "thread-bound". What is the common way to distinguish what was the reason for that exception? I really don't like to parse the MySQL error string.

Code:

try {
   final Entity entity = new Entity();
   entity.setUserName(username);
   entity.setEmail(email);
   dao.persist(entity); // fails on duplicated key violation
} catch (DataIntegrityViolationException e) {
    // trying to figure out if there is an existing entity with the given email or username to return the right error message.

    // that call also fails because getHibernateTemplate() returns null then... so I can't submit a new query.
    if (dao.getByEmail(email) != null) { 
        throw new DuplicateEmailException(email);
    }

    // that call also fails because getHibernateTemplate() returns null then... so I can't submit a new query.
    if (dao.getByUsername(username) != null) {
        throw new DuplicateUsernameException(username);
    }
}

steggo · **Joined:** Mon Apr 22, 2013 4:53 am **Posts:** 2

In addition: When trying to lookup an existing Entity by email within the catch block then I get a org.hibernate.AssertionFailure

"null id in [...] entry (don't flush the Session after an exception occurs)"

Is there any way to recover the current Session or at least to manually close/reopen a new Session? It seems that "thread-bound" sessions are in place here.

Thank you

Akash Mittal · **Joined:** Wed Apr 10, 2013 1:02 am **Posts:** 50

I think you gotta Check what should you set a value of current session context if you are using it with springs thread or application I will try to simulate this meanwhile can u show the full stack trace