I am trying to give second level cache and query cache a try for my project. here is the versio information:

1. Hibernate: 3.3.2
2. EHCache: 1.6.0

However, although query cache seems to be working. It always return result with lazy collections, even if my original query eagerly fetch the collections. For example:

In Service class
// open session
criteria = session.createCriteria(Podcast.class);
criteria.setFirstResult(offset);
org.hibernate.Criteria criteria = session.createCriteria(Podcast.class);
criteria.setFetchMode("podcastCategoryMappings", FetchMode.JOIN);
criteria.add(Restrictions.in("id", podIds));
criteria.setResultTransformer(CriteriaSpecification.DISTINCT_ROOT_ENTITY);
criteria.addOrder(Order.asc("title"));
criteria.setCacheable(true); // turn on cache
podcasts = criteria.list();
// close session

In client class, I expect getting a podcast class, with podcastCategoryMappings collection fetched.

@Test
public void testGetAllPodcasts() {
// first time, it goes through database, and put into cache the query result (id=1), entity (podcast), collections(podcastCategoryMapppings)
List<Podcast> podcasts = _service.getPodcasts(0, 1);

for (Podcast pod: podcasts) {

Set<PodcastCategoryMapping> mappings = pod.getPodcastCategoryMappings();
for (PodcastCategoryMapping mapping: mappings) {
System.out.println("pod title/id: " + pod.getTitle() + "/" + pod.getId() + " category id: " + mapping.getCategoryId());
}


// second time, the results come from cache. I shall expect cache hit for query result, entity(podcast), and collections.
// However, i only see cache hit for query result and entity, not the collections.
podcasts = _service.getPodcasts(0, 1);

// It will fail with LazyInitializationException since collection is not fully initialized when result returned from cache
for (Podcast pod: podcasts) {
System.out.println("pod id: " + pod.getId());

Set<PodcastCategoryMapping> mappings = pod.getPodcastCategoryMappings();
for (PodcastCategoryMapping mapping: mappings) {
System.out.println("pod title/id: " + pod.getTitle() + "/" + pod.getId() + " category id: " + mapping.getCategoryId());
}

}
}


I turned on the debug message for hibernate cache related classes, so that I know what is wrong with cache.
log4j.logger.org.hibernate.cache.ReadWriteCache=TRACE
log4j.logger.org.hibernate.cache.UpdateTimestampsCache=TRACE
log4j.logger.org.hibernate.cache.StandardQueryCache=TRACE


Can someone from hibernate team take a look at this and confirm if this is a bug? I am very close to place this into a project. If this is not working, I guess, I have to manage cache myself, rather than using hibernate to manage the cache. The bottom line is that cache should not return inconsistent result like this.

Thanks.