How to validate database schema programmatically in hibernate with annotations?

Question

It seems that org.hibernate.cfg.Configuration object can be used to perform validation programmatically, by calling the validateSchema method. However, this method needs dialect and databaseMetadata objects. I am using Spring and I can get a hold of AnnotationSessionFactoryBean object from spring context. So far I have the following code:

    AnnotationSessionFactoryBean factory = null;
    factory = (AnnotationSessionFactoryBean) context.getBean("AnnotationSessionFactory");
    Configuration configuration = factory.getConfiguration();

    //the following line does not work, ConnectionHelper hierarchy is not visible outside the package
    ConnectionHelper connectionHelper =  
   new ManagedConnectionProviderConnectionHelper(factory.getHibernateProperties());

    Dialect dialect = Dialect.getDialect(factory.getHibernateProperties());
    Connection connection = null;
    DatabaseMetadata databaseMetadata = null;
    try {
        databaseMetadata = new DatabaseMetadata(connection, dialect);
    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    configuration.validateSchema(dialect, databaseMetadata);

Am I on the right track? ConnectionHelper hierarchy is not visible out of the package so I can’t obtain the connection object that way, in order to construct databaseMetadata. How can I implement this?

EDIT: I think I have made some progress. There is a SchemaValidator class. The code now looks like this:

AnnotationSessionFactoryBean factory = context.getBean("&AnnotationSessionFactory");
Configuration configuration = factory.getConfiguration();       
SchemaValidator validator = new SchemaValidator(configuration);
validator.validate();       

Howerver, now I am getting the following error:

org.hibernate.HibernateException: No local DataSource found for configuration - 'dataSource' property must be set on LocalSessionFactoryBean

Answer 1

In the end, when using Spring this is not that simple. I managed to do it extending the AnnotationSessionFactoryBean like this:

public class SchemaValidatingAnnotationSessionFactoryBean extends
    AnnotationSessionFactoryBean {

public void validateDatabaseSchema() throws DataAccessException {
    logger.info("Validating database schema for Hibernate SessionFactory");
    HibernateTemplate hibernateTemplate = new HibernateTemplate(
            getSessionFactory());
    hibernateTemplate.setFlushMode(HibernateTemplate.FLUSH_NEVER);
    hibernateTemplate.execute(new HibernateCallback() {
        public Object doInHibernate(Session session)
                throws HibernateException, SQLException {
            Connection con = session.connection();
            Dialect dialect = Dialect.getDialect(getConfiguration()
                    .getProperties());
            DatabaseMetadata metadata = new DatabaseMetadata(con, dialect);
            Configuration configuration = getConfiguration();
            configuration.validateSchema(dialect, metadata);
            return null;
        }
    });

}
}

Answer 2

I have found a simpler solution for invoking hibernate mapping validation that works for me : LocalSessionFactoryBean.validateDatabaseSchema() (which effectively does the same thing as the code in Dan's answer above)

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = { "/some-test-context.xml" })
public class TestMapping {

    @Autowired
    ApplicationContext context; 

    @Test
    public void validateSchema() {
        AnnotationSessionFactoryBean factory = (AnnotationSessionFactoryBean)context
                .getBean("&mySessionFactory");
        factory.validateDatabaseSchema(); 
    }
}