[jboss-jira] [JBoss JIRA] (DROOLS-2313) Bad synchronization of ClassAwareObjectStore list of concreteStores can cause ConcurrentModificationException or ArrayIndexOutOfBoundsException while getting session objects

[ https://issues.jboss.org/browse/DROOLS-2313?page=com.atlassian.jira.plugi... ] Donatien RIVIERE updated DROOLS-2313: ------------------------------------- Description: If a thread requests for session objects (using kieSession.getObjects() with or without filters) while another one is inserting objects +of different classes+, there is a chance that a new ConcretObjectStore is added to the concreteStores list at the same time and cause concurrent exception. Example when using kieSession.getObjects().*iterator()* : {noformat} Exception in thread "QueryingThread" java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:901) at java.util.ArrayList$Itr.next(ArrayList.java:851) at org.drools.core.common.ClassAwareObjectStore$CompositeObjectIterator.fetchNextIterator(ClassAwareObjectStore.java:556) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.nextIterator(ClassAwareObjectStore.java:513) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.fetchNext(ClassAwareObjectStore.java:499) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.<init>(ClassAwareObjectStore.java:494) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.<init>(ClassAwareObjectStore.java:487) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.<init>(ClassAwareObjectStore.java:478) at org.drools.core.common.ClassAwareObjectStore$CompositeObjectIterator.<init>(ClassAwareObjectStore.java:546) at org.drools.core.common.ClassAwareObjectStore$CompositeObjectIterator.<init>(ClassAwareObjectStore.java:544) at org.drools.core.common.ClassAwareObjectStore.iterateObjects(ClassAwareObjectStore.java:186) at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.iterator(StatefulKnowledgeSessionImpl.java:679) at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.toArray(StatefulKnowledgeSessionImpl.java:710) at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.toArray(StatefulKnowledgeSessionImpl.java:695) at ft.drools.KieSessionConcurrentTest.lambda$0(KieSessionConcurrentTest.java:125) {noformat} Example when using kieSession.getObjects().*toArray()* : {noformat} Exception in thread "QueryingThread" java.lang.ArrayIndexOutOfBoundsException: 1 at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.toArray(StatefulKnowledgeSessionImpl.java:711) at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.toArray(StatefulKnowledgeSessionImpl.java:695) at ft.drools.KieSessionConcurrentTest.lambda$0(KieSessionConcurrentTest.java:125) {noformat} was: If a thread requests for session objects (using kieSession.getObjects() with or without filters) while another one is inserting objects of different classes, there is a chance that a new ConcretObjectStore is added to the concreteStores list at the same time and cause concurrent exception. Example when using kieSession.getObjects().*iterator()* : {noformat} Exception in thread "QueryingThread" java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:901) at java.util.ArrayList$Itr.next(ArrayList.java:851) at org.drools.core.common.ClassAwareObjectStore$CompositeObjectIterator.fetchNextIterator(ClassAwareObjectStore.java:556) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.nextIterator(ClassAwareObjectStore.java:513) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.fetchNext(ClassAwareObjectStore.java:499) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.<init>(ClassAwareObjectStore.java:494) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.<init>(ClassAwareObjectStore.java:487) at org.drools.core.common.ClassAwareObjectStore$AbstractCompositeIterator.<init>(ClassAwareObjectStore.java:478) at org.drools.core.common.ClassAwareObjectStore$CompositeObjectIterator.<init>(ClassAwareObjectStore.java:546) at org.drools.core.common.ClassAwareObjectStore$CompositeObjectIterator.<init>(ClassAwareObjectStore.java:544) at org.drools.core.common.ClassAwareObjectStore.iterateObjects(ClassAwareObjectStore.java:186) at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.iterator(StatefulKnowledgeSessionImpl.java:679) at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.toArray(StatefulKnowledgeSessionImpl.java:710) at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.toArray(StatefulKnowledgeSessionImpl.java:695) at ft.drools.KieSessionConcurrentTest.lambda$0(KieSessionConcurrentTest.java:125) {noformat} Example when using kieSession.getObjects().*toArray()* : {noformat} Exception in thread "QueryingThread" java.lang.ArrayIndexOutOfBoundsException: 1 at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.toArray(StatefulKnowledgeSessionImpl.java:711) at org.drools.core.impl.StatefulKnowledgeSessionImpl$ObjectStoreWrapper.toArray(StatefulKnowledgeSessionImpl.java:695) at ft.drools.KieSessionConcurrentTest.lambda$0(KieSessionConcurrentTest.java:125) {noformat} -- This message was sent by Atlassian JIRA (v7.5.0#75005)