EhCache + Hibernate Cache is not alive

Question

After configuring EhCache v2.4.5 as the second level cache for hibernate v3.6.7 I get the following error while trying to load all objects of a particular entity using hibernate session. (There is no error for loading the objects for the first time)

java.lang.IllegalStateException: The country Cache is not alive.
at net.sf.ehcache.Cache.checkStatus(Cache.java:2438)
at net.sf.ehcache.Cache.get(Cache.java:1541)
at net.sf.ehcache.hibernate.regions.EhcacheTransactionalDataRegion.get(EhcacheTransactionalDataRegion.java:105)
at net.sf.ehcache.hibernate.strategy.AbstractReadWriteEhcacheAccessStrategy.putFromLoad(AbstractReadWriteEhcacheAccessStrategy.java:90)
at net.sf.ehcache.hibernate.nonstop.NonstopAwareEntityRegionAccessStrategy.putFromLoad(NonstopAwareEntityRegionAccessStrategy.java:180)
at org.hibernate.engine.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:195)
at org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:982)
at org.hibernate.loader.Loader.doQuery(Loader.java:857)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:274)
at org.hibernate.loader.Loader.doList(Loader.java:2533)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2276)
at org.hibernate.loader.Loader.list(Loader.java:2271)
at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:119)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1716)
at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:347)
at dataAccess.CountryDAO.loadAll(CountryDAO.java:80)

My hibernate configuration is:

<property name="hibernate.cache.region.factory_class">
        net.sf.ehcache.hibernate.SingletonEhCacheRegionFactory
</property>
<property name="hibernate.cache.provider_configuration">
    /ehcache.xml
</property>
<property name="hibernate.cache.use_second_level_cache">
    true
</property>
<property name="hibernate.cache.use_query_cache">
    true
</property>

My EhCache configuration is:

<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="ehcache.xsd" updateCheck="true"
monitoring="autodetect" dynamicConfig="true">

<diskStore path="java.io.tmpdir" />

<transactionManagerLookup
    class="net.sf.ehcache.transaction.manager.DefaultTransactionManagerLookup"
    properties="jndiName=java:/TransactionManager" propertySeparator=";" />

<cacheManagerEventListenerFactory
    class="" properties="" />

<defaultCache maxElementsInMemory="0" eternal="false"
    overflowToDisk="true" timeToIdleSeconds="1200" timeToLiveSeconds="1200">
</defaultCache>
<cache name="country"
    maxElementsInMemory="300" eternal="false" overflowToDisk="false"
    timeToIdleSeconds="12000" timeToLiveSeconds="12000" diskPersistent="false"
    diskExpiryThreadIntervalSeconds="120" memoryStoreEvictionPolicy="LRU" />
<cache name="city"
    maxElementsInMemory="300" eternal="false" overflowToDisk="false"
    timeToIdleSeconds="12000" timeToLiveSeconds="12000" diskPersistent="false"
    diskExpiryThreadIntervalSeconds="120" memoryStoreEvictionPolicy="LRU" />
</ehcache>

I have no clue what is going wrong. any ideas?

Answer 1

I don't know the actual reason why this is happening, but I have a suggestion for tracking it down.

Looking at the source code for net.sf.ehcache.Cache, one can see that the 'alive' check just checks an in-memory flag, Cache.cacheStatus. It should be straightforward to run your code under the debugger, and set a breakpoint either in Cache.dispose() (where status is set to Status.STATUS_SHUTDOWN) or even in Cache.CacheStatus.changeState() (to catch any status transition).

You may find that there is in fact a bug with Hibernate, or it may be your usage. Either way, you should be able to find exactly who's changing the state of your cache to 'not alive'.

Good luck.