Wicket exception on shutdown – java.lang.NoClas­sDefFoundError: org/apache/wic­ket/util/lang/Pro­pertyResolver

2012-12-31

Wicket exception on shutdown – java.lang.NoClas­sDefFoundError: org/apache/wic­ket/util/lang/Pro­pertyResolver

This happens when I undeploy a Wicket 1.4.9 application (remove the webapp dir) on Tomcat 6.0.29:

Nov 25, 2010 11:30:49 PM org.apache.catalina.startup.HostConfig checkResources
INFO: Undeploying context []
Nov 25, 2010 11:30:49 PM org.apache.catalina.startup.HostConfig checkResources
WARNING: Error while removing context []
java.lang.NoClassDefFoundError: org/apache/wicket/util/lang/PropertyResolver
        at org.apache.wicket.Application.internalDestroy(Application.java:952)
        at org.apache.wicket.protocol.http.WebApplication.internalDestroy(WebApplication.java:527)
        at org.apache.wicket.protocol.http.WicketFilter.destroy(WicketFilter.java:179)
        at org.apache.catalina.core.ApplicationFilterConfig.release(ApplicationFilterConfig.java:357)
        at org.apache.catalina.core.StandardContext.filterStop(StandardContext.java:4036)
        at org.apache.catalina.core.StandardContext.stop(StandardContext.java:4768)
        at org.apache.catalina.core.ContainerBase.removeChild(ContainerBase.java:924)
        at org.apache.catalina.startup.HostConfig.checkResources(HostConfig.java:1174)
        at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1342)
        at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:303)
        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
        at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1337)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1601)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1590)
        at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.ClassNotFoundException: org.apache.wicket.util.lang.PropertyResolver
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1645)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1491)
        ... 16 more
Nov 25, 2010 11:30:49 PM org.apache.catalina.core.ContainerBase stop
INFO: Container org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/].[apiServlet] has not been started
Nov 25, 2010 11:30:49 PM org.apache.catalina.core.ContainerBase stop
INFO: Container org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/].[jsp] has not been started
Nov 25, 2010 11:30:49 PM org.apache.catalina.core.ContainerBase stop
INFO: Container org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/].[default] has not been started
Nov 25, 2010 11:30:49 PM org.apache.catalina.startup.HostConfig checkResources
WARNING: Error during context [] destroy
java.lang.NoClassDefFoundError: org/apache/wicket/util/lang/PropertyResolver
        at org.apache.wicket.Application.internalDestroy(Application.java:952)
        at org.apache.wicket.protocol.http.WebApplication.internalDestroy(WebApplication.java:527)
        at org.apache.wicket.protocol.http.WicketFilter.destroy(WicketFilter.java:179)
        at org.apache.catalina.core.ApplicationFilterConfig.release(ApplicationFilterConfig.java:357)
        at org.apache.catalina.core.StandardContext.filterStop(StandardContext.java:4036)
        at org.apache.catalina.core.StandardContext.stop(StandardContext.java:4768)
        at org.apache.catalina.core.ContainerBase.destroy(ContainerBase.java:1164)
        at org.apache.catalina.core.StandardContext.destroy(StandardContext.java:4868)
        at org.apache.catalina.startup.HostConfig.checkResources(HostConfig.java:1180)
        at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1342)
        at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:303)
        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
        at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1337)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1601)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1590)
        at java.lang.Thread.run(Thread.java:662)

Solution

From http://www.mail-archive.com/…sg49863.html :

Alexandros Karypidis:

Sun, 21 Mar 2010 02:58:42 –0700
Ok, I've pinpointed the underlying cause. Indeed, the file is simply removed before the destroy() method has a chance to clean up. I verified this by using this ugly hack:

  1. Adding a field:

    private InputStream wicketJarProtector;

  2. In WicketFilter.init() I open the wicket jar to „protect“ it from deletion:

    wicketJarProtector = filterConfig.getServletContext().getResourceAsStream("/WEB-INF/lib/wicket.jar");

  3. In WicketFilter.destroy() I close the file handle:

    wicketJarProtector.close();

This prevents the file from being deleted, undeployment completes successfully.

I'm not sure how to „properly“ fix this… Any ideas?

Igor Vaynberg:

I can kind of see what is going on, the YourApplication class is loaded using a different classloader then the wicket jar. and tomcat cleans it up. fair enough. but, YourApplication class extends Application which is inside the jar, so tomcat should not be cleaning it up…makes no sense. How can the entire jar be gone if one of the classes that was loaded from it is still being used. It may be an optimization they do but its may be backfiring in this particular case. You may have to use your jar protector as a permanent workaround.

  • igor
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