I get a ClassCastException when I try to do the following:
Map cacheEntries = sessionFactory.getStatistics().getSecondLevelCacheStatistics(regionName).getEntries();

Any pointers to what could be wrong here?

I am using:
Java 1.6
Hibernate 3.5.3
GWT 2.0

I get the same exception when I use EhCache as well. However, I was expecting Hashtable cache to work.

My second level cache config is
<!-- second-level cache related properties -->
<property name="cache.provider_class">org.hibernate.cache.HashtableCacheProvider</property>
<property name="hibernate.cache.use_second_level_cache">true</property>
<property name="hibernate.cache.use_structured_entries">true</property>
<property name="hibernate.cache.use_query_cache">true</property>

The stack trace of the exception
Caused by: java.lang.ClassCastException: org.hibernate.cache.QueryKey cannot be cast to org.hibernate.cache.CacheKey
at org.hibernate.stat.ConcurrentSecondLevelCacheStatisticsImpl.getEntries(ConcurrentSecondLevelCacheStatisticsImpl.java:57)
at xx.server.util.HibernateUtil.printCacheStatistics(HibernateUtil.java:68)
at xx.server.staff.ManageStaffServiceImpl.searchStaff(ManageStaffServiceImpl.java:147)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:562)
... 22 more

Thanks.

I was aware of the bug, but my understanding was that it was resolved in Hibernate 3.3, and I am using version 3.5.

Hi Sunesh,
I am facing the same problem. Whther did you find solution for avioding this exception.

java.lang.ClassCastException: org.hibernate.cache.QueryKey cannot be cast to org.hibernate.cache.CacheKey
at org.hibernate.stat.SecondLevelCacheStatistics.getEntries(SecondLevelCacheStatistics.java:74)
at com.adenyo.app.adserver.controllers.CacheManagerController.manageCache(CacheManagerController.java:90)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.doInvokeMethod(HandlerMethodInvoker.java:710)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:167)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:414)
at

Please let me know if you have a solution. Or whether you had applied any patch.

My hibernate version is
3.3.2.GA

I am facing same issue in hibernate ver 4.1.4

Is there any workaround or fix to this issue?

Hibernate 4.x is no longer under development. You need to try it with 5.2 as the bug might have been fixed a very long time ago.