[OPENJPA-2538] Classloader memory leak in PCRegistry

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Invalid
• Affects Version/s: 2.3.0
• Component/s: Enhance, osgi
• Assignee: Richard G. Curtis
• Reporter: Grzegorz Grzybek
• Created: 23/Oct/14 12:41
• Updated: 31/Oct/14 12:32
• Resolved: 28/Oct/14 13:37

Description

I'm using OpenJPA in OSGi environment (namely: JBoss Fuse 6.1). We had nasty NullPointerException in Felix when trying to load source code during initialization of class metadata. This line returned duplicate entity classes - half of them were from old revision of a bundle and half - from new revision.

I tracked down the problem to the point, where org.apache.openjpa.enhance.PCRegistry#register() was invoked as part of constructing new instances of entity classes (static initialization injected during class enhancement). Although _metas is instance of ConcurrentReferenceHashMap with weak keys, the keys (entity classes) had other hard references too. Here's a list of the hard refs I got from simple heap dump:

• org.apache.openjpa.meta.MetaDataRepository#_impls
• org.apache.openjpa.meta.InheritanceComparator#_base
• org.apache.openjpa.enhance.PCRegistry.Meta#pcSuper
• org.apache.openjpa.meta.MetaDataRepository#_oids

so on every bundle refresh we have next bunch of classes in _metas...