Bug 339948

Description Cameron Bateman 2011-03-14 17:34:40 EDT

Build Identifier: 

We tried following the advice at http://wiki.eclipse.org/CDO/Tweaking_Performance#Loading_Partial_Collections_.E2.80.93_CDOCollectionLoadingPolicy with this code on our client:

CDOCollectionLoadingPolicy policy =
      CDOUtil.createCollectionLoadingPolicy(0, 500);
    session.options().setCollectionLoadingPolicy(policy);

However, this resulted in the following failure when we attempted to execute our custom OCL queries.  It appears that during the list copy, it tries to cast each item to EObject.  However, there are some elements in the list that are of type CDORevisionUtil$Uninitialized.  I confirmed this fact using the debugger.  Note that this occurs only if the policy code is called on the very first query, but then will break all subsequent query on the server.  It appears that there is a lot one-time lazy init the first time a query is executed and then much subsequently.

!ENTRY org.eclipse.ocl 4 10 2011-03-14 15:12:39.247
!MESSAGE Evaluation failed with an exception: org.eclipse.emf.cdo.common.revision.CDORevisionUtil$Uninitialized cannot be cast to org.eclipse.emf.ecore.EObject
!STACK 0
java.lang.ClassCastException: org.eclipse.emf.cdo.common.revision.CDORevisionUtil$Uninitialized cannot be cast to org.eclipse.emf.ecore.EObject
	at org.eclipse.emf.ecore.util.DelegatingEcoreEList.resolve(DelegatingEcoreEList.java:279)
	at org.eclipse.emf.common.util.DelegatingEList.get(DelegatingEList.java:236)
	at org.eclipse.emf.common.util.AbstractEList$EIterator.doNext(AbstractEList.java:709)
	at org.eclipse.emf.common.util.AbstractEList$EIterator.next(AbstractEList.java:696)
	at java.util.AbstractCollection.addAll(Unknown Source)
	at java.util.LinkedHashSet.<init>(Unknown Source)
	at org.eclipse.ocl.util.CollectionUtil.createNewCollection(CollectionUtil.java:1108)
	at org.eclipse.ocl.ecore.EcoreEvaluationEnvironment.coerceValue(EcoreEvaluationEnvironment.java:304)
	at org.eclipse.ocl.ecore.EcoreEvaluationEnvironment.navigateProperty(EcoreEvaluationEnvironment.java:246)
	at org.eclipse.ocl.ecore.EcoreEvaluationEnvironment.navigateProperty(EcoreEvaluationEnvironment.java:1)
	at org.eclipse.ocl.EvaluationVisitorImpl.visitPropertyCallExp(EvaluationVisitorImpl.java:1925)
	at org.eclipse.ocl.ecore.impl.PropertyCallExpImpl.accept(PropertyCallExpImpl.java:238)
	at org.eclipse.ocl.EvaluationVisitorImpl.visitIteratorExp(EvaluationVisitorImpl.java:1423)
	at org.eclipse.ocl.ecore.impl.IteratorExpImpl.accept(IteratorExpImpl.java:114)
	at org.eclipse.ocl.AbstractEvaluationVisitor.visitExpression(AbstractEvaluationVisitor.java:247)
	at org.eclipse.ocl.internal.evaluation.QueryImpl.evaluate(QueryImpl.java:129)
	at biz.tradescape.mmt.cdo.query.OCLQueryHandler.evaluate(Unknown Source)
	at biz.tradescape.mmt.cdo.query.OCLQueryHandler.executeQuery(Unknown Source)
	at org.eclipse.emf.cdo.internal.server.QueryManager$QueryContext.run(QueryManager.java:284)
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
	at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
	at java.util.concurrent.FutureTask.run(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)

Reproducible: Always