Class ServletContextCleaner

java.lang.Object
org.apache.commons.logging.impl.ServletContextCleaner
All Implemented Interfaces:
EventListener, javax.servlet.ServletContextListener

public class ServletContextCleaner extends Object implements javax.servlet.ServletContextListener
This class is capable of receiving notifications about the undeployment of a webapp, and responds by ensuring that commons-logging releases all memory associated with the undeployed webapp.

In general, the WeakHashtable support added in commons-logging release 1.1 ensures that logging classes do not hold references that prevent an undeployed webapp's memory from being garbage-collected even when multiple copies of commons-logging are deployed via multiple classloaders (a situation that earlier versions had problems with). However there are some rare cases where the WeakHashtable approach does not work; in these situations specifying this class as a listener for the web application will ensure that all references held by commons-logging are fully released.

To use this class, configure the webapp deployment descriptor to call this class on webapp undeploy; the contextDestroyed method will tell every accessible LogFactory class that the entry in its map for the current webapp's context classloader should be cleared.

Since:
1.1
Version:
$Id: ServletContextCleaner.java 1432580 2013-01-13 10:41:05Z tn $
  • Field Details

    • RELEASE_SIGNATURE

      private static final Class[] RELEASE_SIGNATURE
  • Constructor Details

    • ServletContextCleaner

      public ServletContextCleaner()
  • Method Details

    • contextDestroyed

      public void contextDestroyed(javax.servlet.ServletContextEvent sce)
      Invoked when a webapp is undeployed, this tells the LogFactory class to release any logging information related to the current contextClassloader.
      Specified by:
      contextDestroyed in interface javax.servlet.ServletContextListener
    • contextInitialized

      public void contextInitialized(javax.servlet.ServletContextEvent sce)
      Invoked when a webapp is deployed. Nothing needs to be done here.
      Specified by:
      contextInitialized in interface javax.servlet.ServletContextListener