POF & fromBinary

Question

Hi,
I am in the process of making all my Java objects EvolvablePortableObject. I was using Externalizable, but from what i can tell, serializing with POF creates a smaller memory footprint and appears to be new new preferred way to store objects in a grid(correct?).
Things were working fine until i tried doing some deletes. When my map listener fired off on the entryDeleted method in the ReadWriteBackingMap, i got an Exception. The code that fails is
          Object oKey = evt.getKey() instanceof Binary ? ExternalizableHelper
                    .fromBinary((Binary) evt.getKey()) : evt.getKey();
The fromBinary is trying to use the DefaultSerializer, which obviously will not work due to the fact i am doing POF. Is there a work around for this? Am i doing something wrong? Any reason I would not want to use POF for all my objects? I am using 3.4 RC3 code. Here is the complete stacktrace.
2008-09-11 17:09:45.478 Oracle Coherence GE 3.4/403 Release Candidate 3 <Error> (thread=DistributedCacheWorker:3, member=8): (Wrapped) java.io.IOException: unsupported type / corrupted stream: 78
at com.tangosol.util.ExternalizableHelper.readObjectInternal(ExternalizableHelper.java:2222)
at com.tangosol.util.ExternalizableHelper.readObject(ExternalizableHelper.java:2209)
at com.tangosol.io.DefaultSerializer.deserialize(DefaultSerializer.java:60)
at com.tangosol.util.ExternalizableHelper.deserializeInternal(ExternalizableHelper.java:2643)
at com.tangosol.util.ExternalizableHelper.fromBinary(ExternalizableHelper.java:256)
at com.tangosol.util.ExternalizableHelper.fromBinary(ExternalizableHelper.java:224)
at com.thomson.legal.vertical.sooem.CacheListener.entryDeleted(CacheListener.java:23)
at com.tangosol.util.MapEvent.dispatch(MapEvent.java:199)
at com.tangosol.util.MapEvent.dispatch(MapEvent.java:164)
at com.tangosol.util.MapListenerSupport.fireEvent(MapListenerSupport.java:556)
at com.tangosol.net.cache.OldCache.dispatchEvent(OldCache.java:1718)
at com.tangosol.net.cache.OldCache$Entry.discard(OldCache.java:2018)
at com.tangosol.net.cache.OldCache.remove(OldCache.java:323)
at com.tangosol.net.cache.LocalCache.remove(LocalCache.java:137)
at com.tangosol.net.cache.ReadWriteBackingMap.remove(ReadWriteBackingMap.java:867)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$Storage.remove(DistributedCache.CDB:49)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache.onRemoveRequest(DistributedCache.CDB:34)
at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$RemoveRequest.run(DistributedCache.CDB:1)
at com.tangosol.coherence.component.util.DaemonPool$WrapperTask.run(DaemonPool.CDB:1)
at com.tangosol.coherence.component.util.DaemonPool$WrapperTask.run(DaemonPool.CDB:24)
at com.tangosol.coherence.component.util.DaemonPool$Daemon.onNotify(DaemonPool.CDB:49)
at com.tangosol.coherence.component.util.Daemon.run(Daemon.CDB:37)
at java.lang.Thread.run(Thread.java:619)
On a side note, it did delete my objects from the cache.
thanx
kevin

Answer 1

Hi Kevin,
Instead of using ExternalizableHelper directly you can use BackingMapManagerContext (also see cache configuration parameter macros: http://wiki.tangosol.com/display/COH33UG/Parameter+Macros) , which has to/from internal converters associated with it, for example:
<!DOCTYPE cache-config SYSTEM "cache-config.dtd">
<cache-config>
    <caching-scheme-mapping>
        <cache-mapping>
            <cache-name>test</cache-name>
            <scheme-name>test</scheme-name>
        </cache-mapping>
    </caching-scheme-mapping>
    <caching-schemes>
        <distributed-scheme>
            <scheme-name>test</scheme-name>
            <backing-map-scheme>
                <local-scheme>
                    <listener>
                        <class-scheme>
                            <class-name>Main</class-name>
                            <init-params>
                                <init-param>
                                    <param-type>com.tangosol.net.BackingMapManagerContext</param-type>
                                    <param-value>{manager-context}</param-value>
                                </init-param>
                            </init-params>
                        </class-scheme>
                    </listener>
                </local-scheme>
            </backing-map-scheme>
        </distributed-scheme>
    </caching-schemes>
</cache-config>
import com.tangosol.net.BackingMapManagerContext;
import com.tangosol.net.CacheFactory;
import com.tangosol.util.Converter;
import com.tangosol.util.MapEvent;
import com.tangosol.util.MultiplexingMapListener;
* dimitri Sep 13, 2008 7:36:55 PM
public class Main extends MultiplexingMapListener
    BackingMapManagerContext m_ctx;
    public Main(BackingMapManagerContext ctx)
        m_ctx = ctx;
    protected void onMapEvent(MapEvent evt)
        Converter keyFromInternal = m_ctx.getKeyFromInternalConverter();
        Converter valFromInternal = m_ctx.getValueFromInternalConverter();
        Object oKey = keyFromInternal.convert(evt.getKey());
        Object oValueNew = valFromInternal.convert(evt.getNewValue());
        Object oValueOld = valFromInternal.convert(evt.getOldValue());
        CacheFactory.log(
            "Event: " + evt.getId() +
            " key: " + oKey +
            " new vaue: " + oValueNew +
            " old value: " + oValueOld,
            CacheFactory.LOG_DEBUG);
    }Regards,
Dimitri