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ClassNotFoundException When Deploying EAR file that Refers to a WAR library on Weblogic

On my weblogic server(11g) I have a web appliation MyApp.ear, a library war file MyLib.war. Both deployed to the same managed server. MyLib.war is deployed as a shared library. MyEjb.jar is using classes located in MyLib.war - WEB-INF/classes. When I tried to deploy MyApp.ear, I got a CLASSNOTFOUND exception complaining the class in MyLib.war - WEB-INF/classes is not found.

weblogic.application.ModuleException: Exception preparing module: EJBModule(MyEjb.jar)
[EJB:011023]An error occurred while reading the deployment descriptor. The error was:
 org/my/lib/someclass.
 ....
 caused by 
 Caused By: java.lang.ClassNotFoundException: org.my.lib.someclass
	at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:297)

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I could see the class is indeed located in MyLib.war -> WEB-INF/classes folder.

I have tried to add the following in either weblogic-application.xml or weblogic.xml:

<library-ref>
    <library-name>MyLib</library-name>
    <exact-match>false</exact-match>
</library-ref>

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(MyLib is defined as EXTENSION name in MyLib.war's MANIFEST.MF).

What am I missing? There is no different version of jar files in MyApp.ear and MyLib.war.

The structure of the ear and war files:

MyApp.ear
      META-INF
            MANIFEST.MF
            weblogic-application.xml
      lib
      APP-INF
      MyEjb.jar
            META-INF
      MyWeb.war
            META-INF
            WEB-INF
                  weblogic.xml
                  web.xml
MyLib.war
      META-INF
            MANIFEST.MF
      WEB-INF
            classes
            lib
            weblogic.xml

girionis

Try something. In the weblogic console go to Deployments. Then click on the war file and set the "Deployment Order" to a value lower than the one you have in the "Deployment Order" of your ear file. Try this and if it does not work we can think of something else.

nscappdev

ASKER

Thank you for your reply girionis. I have already tried that. It didn't help.

From what I read about weblogic classloader hierarchy:

The classloader implementation first checks its cache to see if the requested class has already been loaded. This class verification improves performance in that its cached memory copy is used instead of repeated loading of a class from disk. If the class is not found in its cache, the current classloader asks its parent for the class. Only if the parent cannot load the class does the classloader attempt to load the class. If a class exists in both the parent and child classloaders, the parent version is loaded.

Just by adding the library-ref in the weblogic-application.xml should allow all the child classloaders of the application classloader to load the library. Seems like the class for the WAR isn't loaded anywhere.

I also verified that there are no reference jar version conflict in ear's lib and the library war file's lib.

What else could be the cause?

Thanks!

girionis

It is possible that the MyLib.war is picked up by a different classloader. Can you make the MyLib.war file a jar and try again?

nscappdev

ASKER

MyLib.war needs other jars from its lib folder. If I just packed the classes in MyLib.war as a jar, I'm able to deploy MyApp.ear. Does that mean MyLib.war was picked up by another classloader??

However, packing it in a jar won't solve the problem because when MyLib is invoked from MyApp, it needs other jars that are in its own lib folder.

Also, I can't include MyLib.war in MyApp.ear as the war library is used by several other application deployed to the same managed server.

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girionis

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nscappdev

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Anyways, thank you for the help! girionis