Upgrading to EhCache 1.6.2 with Hibernate to enable JMX Monitoring

I couldn't (easily) find this answer, so here goes: Yes, it is completely OK to use 1.6.2 with Hibernate (3.3.2 in my case).

For whatever reason, the maven package hibernate-ehcache uses an old version of ehcache, version 1.2.3. This version doesn't support JMX (which is why I wanted to upgrade) but supposedly there are significant performance improvements in newer ehcache versions as well.

My app is maven/spring/hibernate, so first in your spring config make sure to use the Singleton version of the ehcache provider, otherwise you won't be able to turn on JMX:

<entry key="hibernate.cache.provider_class" value="net.sf.ehcache.hibernate.SingletonEhCacheProvider" />

Then in maven, exclude the old version and bring in the new one:

        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-ehcache</artifactId>
            <version>3.3.2.GA</version>
            <exclusions>
                <exclusion>
                    <groupId>net.sf.ehcache</groupId>
                    <artifactId>ehcache</artifactId>
                </exclusion>
            </exclusions>    
        </dependency>
        <dependency>
            <groupId>net.sf.ehcache</groupId>
            <artifactId>ehcache</artifactId>
            <version>1.6.2</version>
        </dependency>

Finally you will need to register JMX mbeans for your cache when your app starts:

        CacheManager manager = CacheManager.getInstance();
        MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
        ManagementService.registerMBeans(manager, mBeanServer, false, false, false, true);

Now you can see how many items are in each cache region using JConsole. Enjoy!