Resolve Jbosscache using JNDI

analogboy · **Joined:** Mon Feb 02, 2004 4:18 pm **Posts:** 16

I'm using Spring to wire an application together, but intead of linking Hibernate and TreeCache thru JMX, I'd prefer to pass the cache provider to Hibernate using JNDI. The reason is that I'd prefer to wire everything using Spring rather than depending on JMX to provide a similar function.

In my Spring config, I'd like to be able to swap between datasources and cache providers depending on the platform. Is there any else in the same boat as myself?

I was thinking of writing an implementation that would perform the JNDI resolution and then delegates the methods from the interface. Then I could still use the current implementation (setting the cache.provider_class property to xxx.MyCacheProviderDelegate), but the calls would be delegated to the correct implementation.

Any ideas folks?

mpruden · **Joined:** Fri Sep 10, 2004 9:46 am **Posts:** 10

I have implemented what you require. To do it I copied the two java classes TreeCache, and TreeCacheProvider from the net.sf.hibernate.cache into my own package, and changed the constructor of TreeCache as follows, this handles the lookup of TreeCache from JNDI. Then you register you new Provider class in the Hibernate configuration, and ensure there is a MBean depends clause on the Tree Cache sevice. I have tidied up the code further, but only cosmetic, can post the full code if you want it.

Code:

public TreeCache(String regionName, Properties props) 
   throws CacheException {

   this.regionName = '/' + regionName.replace('.', '/');
   try {
            synchronized (TreeCache.class) {
                if (cache==null) {
                    cache = (TreeCache)new InitialContext().lookup( "java:/TreeCache" );
                    if ( cache == null ) 
                       throw new CacheException("Failed to lookup TreeCache in JNDI");
                }
            }
   }
   catch (Exception e) {
      throw new CacheException(e);
   }
}

steve · **Posted:** Wed Oct 27, 2004 9:56 am

Funny. I just added this to the JBoss-Hibernate integration code. It will be available in the next 4.0 release as well as the next 3.2 release (as well as the HEAD branch).

It's a little different. It changes the Hibernate MBean to add a new attribute named "DeployedTreeCacheJndiName". Just set the "CacheProviderClass" attribute to "org.jboss.hibernate.cache.DeployedTreeCacheProvider" and then set the "DeployedTreeCacheJndiName" attribute to the place TreeCache is being bound into JNDI.

Note that this is only available OOTB with TreeCache 1.2 (the automatic binding of the TreeCache, that is).

mpruden · **Joined:** Fri Sep 10, 2004 9:46 am **Posts:** 10

Steve Can I make a suggestion.

Change the existing net.sf.cache.TreeCache constructor to the following.

Code:

public TreeCache(String regionName, org.jboss.cache.TreeCache cache) 
    throws CacheException {
    this.cache = cache;
    this.regionName = '/' + regionName.replace('.', '/');
}

Then in the CacheProvider implementation perform all the resolution of the jboss TreeCache object, either by JNDI, or by constructing it manually.

This decouples the construction of the jboss TreeCache keeping it in the factory, leaving the net.sf.hibernate.cache.Cache implementation to just invoke the methods in the cache. eg

Code:

public class TreeCacheProvider implements CacheProvider
{
    public Cache buildCache(String regionName, Properties properties) throws CacheException {
        return new JBossTreeCache(regionName, getCache());
    }

    public long nextTimestamp() {
        return System.currentTimeMillis() / 100;
    }

    // reference to the tree cache we discovered
    private static TreeCache cache;

    // What we lookup in JNDI to discobver the Tree Cache
    private static final String TREECACHE_JNDI_REF = "java:/TreeCache";

    public static TreeCache getCache() throws CacheException {
        if ( cache != null ) return cache;
        try {
            synchronized (JBossTreeCache.class) {
                if (cache==null) {
                    cache = (TreeCache)new InitialContext().lookup( TREECACHE_JNDI_REF );
                    if ( cache == null ) throw new CacheException("Failed to lookup TreeCache in JNDI");
                }
            }
        }
        catch (Exception e) {
            throw new CacheException(e);
        }
        return cache;
    }
}

steve · **Posted:** Wed Oct 27, 2004 12:51 pm

I thought about it, but that is not how its done in the other impls. I'd rather leave this as-is for consistency sake.

And no I don't feel like changing all of them :)

mpruden · **Joined:** Fri Sep 10, 2004 9:46 am **Posts:** 10

Quote:

And no I don't feel like changing all of them :)

Are you looking for a volunteer? I dont have developer status on project, so this would be the only issue.

alesj · **Posted:** Mon Nov 14, 2005 8:02 am

How should my cache -service.xml file look like?
Since now if I follow the docs on JBossTreeCache this is how they bind TreeCache to jndi:

Code:

    <mbean
        code="org.jboss.invocation.jrmp.server.JRMPProxyFactory"
        name="mydomain:service=proxyFactory,type=jrmp,target=factory">
        <attribute name="InvokerName">jboss:service=invoker,type=jrmp</attribute>
        <attribute name="TargetName">jboss.cache:service=TreeCache</attribute>
        <attribute name="JndiName">java:/treeCache</attribute>
        <attribute name="InvokeTargetMethod">true</attribute>
        <attribute name="ExportedInterface">org.jboss.cache.TreeCacheMBean</attribute>
        <attribute name="ClientInterceptors">
            <interceptors>
                <interceptor>org.jboss.proxy.ClientMethodInterceptor</interceptor>
                <interceptor>org.jboss.proxy.SecurityInterceptor</interceptor>
                <interceptor>org.jboss.invocation.InvokerInterceptor</interceptor>
            </interceptors>
        </attribute>
        <depends>jboss:service=invoker,type=jrmp</depends>
        <depends>jboss.cache:service=TreeCache</depends>
    </mbean>           

But this way the proxy bean exposes only TreeCacheMBean interface and not TreeCache object. So I get a ClassCastException in JndiBoundTreeCacheProvider.

Rgds, Ales

alesj · **Posted:** Mon Nov 14, 2005 8:15 am

Found it:

<property name="hibernate.cache.provider_class" value="org.jboss.ejb3.entity.TreeCacheProviderHook"/>
<property name="hibernate.treecache.mbean.object_name" value="jboss.cache:service=TreeCache"/>

Rgds, Ales