IBM Websphere portlet classloader issue

I am currently working on a portlet that is using the commons-collections jar file and am getting a NoSuchMethodError. To resolve this issue I ne开发者_StackOverflow中文版ed to change the classloader of my WAR file from PARENT_FIRST to PARENT_LAST (in the application.xml file).

However, when I do this my portlet will not launch and when I log into the console it displays the message "The portlet is temporarily disabled". If I change the classloader back to PARENT_FIRST then it will launch again but then I get the NoSuchMethodError.

Does anybody have any suggestions on how to fix this issue ?

I am not sure how, but today I started getting error messages in the logs when I was getting "The portlet is temporarily disabled". I was getting a java.lang.LinkageError which was down to the fact that I had the servlet-api-2.5.jar and a jaxb jar which was conflicting with webshpere j2ee.jar. Once I removed these dependencies and set the classloader to PARENT_LAST, it seems to work properly. It seems that a lot of people face similar issues. The link below is also useful http://forum.springsource.org/showthread.php?33663-dispatcher-servlet-quot-not-a-servlet-class-quot-in-websphere

@MTH,

please try adding commons-collections as a shared library. See here for an example on how others have used shared library support [1]. That will give you the steps, just do it for the jars that you need to override/replace from WAS's classloader

[1] http://portals.apache.org/jetspeed-2/deployguide/deploying-jetspeed-to-websphere.html#section_4_2

thanks, dims

You haven't provided any logs... but still, one of the most important things to look out for when setting your application to run PARENT_LAST is that your application isn't bundled with any system-level classes that may conflict with the ones provided by WebSphere Portal. For example, classes that pertain to the Portlet specification or the JavaEE specification.