Hibernate Search and Ehcache

atrilogy · **Joined:** Mon Nov 28, 2005 12:32 pm **Posts:** 3

Relevant Environment

Hibernate Search v3.4.1
Hibernate Core v3.6.7
EHcahce v2.4.1

Solution I am trying to achieve is to back Lucene indexes via the ehcache and i was given to understand from reading the documentation here (http://relation.to/18621.lace) that you can specify to fetch the entities from the second level cache before extracting the same from the DB.

In our Search API I have the following

Code:

      FullTextQuery fullTextQuery = buildQuery(filterParameters, false);
      
      fullTextQuery.initializeObjectsWith(ObjectLookupMethod.SECOND_LEVEL_CACHE, DatabaseRetrievalMethod.QUERY);
      List<Object> results = new ArrayList<Object>();
      Iterator<?> iterator = fullTextQuery.iterate();
      
      while (iterator.hasNext()) {
         Object element = iterator.next();
         results.add(element);
      }

While this does not break anything and search results behave and come back like we expect We get no In Memory Hits for the second level cache. I have verified this by observing the real time cache statistics via jconsole.

So we have
Entities in Second Level Cache (memory)
Projected attributes of the Entities in Index (directory)

but I am missing something since it never seems to extract the entities that resulted in the hits from the second level cache.

Any ideas or am I missing something obvious? Should this be even possible?

Thanks in advance
-a

sanne.grinovero · **Posted:** Wed Sep 07, 2011 1:57 pm

Quote:

Any ideas or am I missing something obvious? Should this be even possible?

Yes this should be possible.

Did you enable second level caching for these entities ?
Does it work when doing a simple load ?
Did you enable Hibernate statistics ?

atrilogy · **Joined:** Mon Nov 28, 2005 12:32 pm **Posts:** 3

Code:

<property name="jpaPropertyMap">
         <props>
            <!-- <prop key="hibernate.show_sql">true</prop> -->
            <!-- <prop key="hibernate.format_sql">true</prop> -->
            <!-- Cache-->
            <prop key="hibernate.cache.use_second_level_cache">${hibernate.cache.use.second.level.cache}</prop>
            <prop key="hibernate.cache.use_query_cache">${hibernate.cache.use.query.cache}</prop>
            <prop key="hibernate.generate_statistics">${hibernate.cache.generate.statistics}</prop>
            <prop key="hibernate.cache.use_structured_entries">${hibernate.cache.use.structured.entries}</prop>
            <prop key="hibernate.cache.region.factory_class">net.sf.ehcache.hibernate.SingletonEhCacheRegionFactory</prop>
            <prop key="hibernate.cache.provider_configuration_file_resource_path">/ehcache/ehcache.xml</prop>
      

is a snippet of the cache settings in the dbmsContext where all the properties are set to true so

Quote:

Did you enable second level caching for these entities ?

Yes via the ehcache.xml and correspondingly via the

Code:

@Cache(usage=CacheConcurrencyStrategy.READ_WRITE)

annotation for the domain object
In looking @ jconsole cache statistics I see the ObjectStoreMemmoryCount go up so I know these are being cached

Does it work when doing a simple load ?
I have not tried this yet since all of our results or catalog page get driven by executing against the search service, but I will write a simple load and see what I get

Did you enable Hibernate statistics ?
I am assuming you mean "hibernate.generate_statistics" and that has been set to true as in point 1.