[GERONIMO-4545] TomcatJAASRealm keeps reference to undeployed EAR/WAR's classloader

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 2.2
• Fix Version/s: 2.1.5, 2.2
• Component/s: Memory Leaks, security, Tomcat
• Security Level: public (Regular issues)
• Assignee: Haihong Xu
• Reporter: Janko Heilgeist
• Created: 19/Feb/09 09:52
• Updated: 02/Apr/10 01:36
• Resolved: 22/May/09 02:25

Description

Another issue where an undeployed WAR's classloader is not GCed.

--> org.apache.geronimo.tomcat.realm.TomcatJAASRealm@0x2aaab10ab438 (180 bytes)  (field container:) exclude
--> org.apache.geronimo.tomcat.GeronimoStandardContext@0x2aaab322d390 (749 bytes) (field parentClassLoader:) exclude
--> org.apache.geronimo.kernel.config.MultiParentClassLoader@0x2aaab2e9b2e0 (156 bytes) (field parents:) exclude
--> [Ljava.lang.ClassLoader;@0x2aaab0b97958 (88 bytes) (Element 1 of [Ljava.lang.ClassLoader;@0x2aaab0b97958:) exclude
--> org.apache.geronimo.kernel.config.ChildrenConfigurationClassLoader@0x2aaab05e8bc0 (115 bytes) (field parent:) exclude
--> org.apache.geronimo.kernel.config.MultiParentClassLoader@0x2aaab2e9b230 (156 bytes) exclude 

It looks to me like the TomcatJAASRealm (its name is "DefaultJAASRealm") is a standard realm that is used by all WARs without explicit configuration. Setting the realm of a GeronimoStandardContext makes the context store a reference to its realm AND makes the realm store a reference to the context (see org.apache.catalina.core.ContainerBase#setRealm() which GeronimoStandardContext inherits). Thus, the default realm's reference is always directed to the context of the WAR deployed most recently. This reference keeps the context from being GCed even if the corresponding WAR has been undeployed in the meantime.