未在cfg中映射的休眠加载实体

Question

I have been using Hibernate for some time with great success. However I ran into an issue yesterday and an answer here would save a lot of debugging time in the future.

I forgot to add a hibernate mapping to my hibernate.cfg for a new Entity.

I would have expected to get some sort of run time exception when I tried to load this entity, but instead it just loaded nothing and continued as if everything was fine.

I am using the following code to load the entities.

protected List<T> findByCriteria(Session session, Criterion... criterion) {
    Criteria crit = session.createCriteria(getPersistentClass()); /getPersistentClass returns a Class<T>
    for (Criterion c : criterion) {
        crit.add(c);
    }
    return crit.list();
}

I would like an error if I try an load an Entity that is not mapped in my hibernate.cfg.

Is there a way to do this?

Answer 1

Are you running your code in j2EE server. As posted in previous answer are you using annotations on your entity class ? If so try removing entity annotation.

Answer 2

In the end, I abandoned the mappings in the hibernate.cfg and added the following method when building the Configuration object for my SessionFactory.

private static void addAnnotatedEntityClasses(Configuration configuration) {
    Reflections reflections = new Reflections("com.mypackage");
    Set<Class<?>> classes = reflections.getTypesAnnotatedWith(Entity.class);

    logger.debug("Adding Hibernate Mapping for: ");
    for (final Class<?> clazz : classes) {
        logger.debug(clazz.getName());
        configuration.addAnnotatedClass(clazz);
    }
}

This finds all classes in my project with the Entity annotation and adds a mapping.

This uses the Reflections library for simplicity. Found here:

<dependency>
    <groupId>org.reflections</groupId>
    <artifactId>reflections</artifactId>
    <version>0.9.9-RC1</version>
</dependency>