[ https://issues.apache.org/jira/browse/POOL-161?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Sylvain Laurent updated POOL-161: --------------------------------- Attachment: TestGenericObjectPoolClassLoader.patch.txt added TestGenericObjectPoolClassLoader.patch.txt to showcase the problem. > ContextClassLoader problems for the Evictor thread > -------------------------------------------------- > > Key: POOL-161 > URL: https://issues.apache.org/jira/browse/POOL-161 > Project: Commons Pool > Issue Type: Bug > Affects Versions: 1.5.4 > Reporter: Sylvain Laurent > Fix For: 2.0 > > Attachments: TestGenericObjectPoolClassLoader.patch.txt > > > Since a single Timer is used for several GenericObjectPool instances, this > may create classloader issues and a memory leak of one classloader : > Let's imagine the following scenario : > - commons-pool.jar is in the classpath of a webapp container (e.g. tomcat). > - 2 webapps A and B are deployed, each creating an instance of > GenericObjectPool for its own usage. > - each webapp makes use of the idle object evictor and sets a positive number > for minIdle > - first, webapp A instantiates its GenericObjectPool. Since this is the first > TimerTask to be created, the Timer instance is created, thus creating a > Thread whose ContextClassLoader is the current one, that is webapp A's > ContextClassLoader. > The TimerTask properly creates instances of idle objects in the pool, making > use of the ObjectFactory provided by A. > - then B instantiates its GenericObjectPool. A new TimerTask is created, and > it tries to invoke the ObjectFactory provided by B. But when it needs a class > that only exists in B webapp, it cannot find it because the > ContextClassLoader of the Timer Thread is A's classloader. > Other side effect : if webapp A is undeployed, but B is still running, then > A's webappClassLoader cannot be GCed because the Timer Thread keeps a strong > reference to A's classloader (as its context classloader). -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.