Jar within War - NoClassDefFound Exception

Question

Hi All,

I have deployed 2 apps as app1.war and app2.war on jboss. These two apps use a common java package, say, myPackage. Earlier my wars looked like this

========================================================================

app[12].war/
-----web.xml
-----app specific classes (.class files like)
-----appClass1.class
-----appClass2.class etc..
-----WEB-INF/
-----myPackage/ (this was just a folder under the war, not a jar package)
----------classes belonging to the common package like
----------common_class1.class
----------common_class2.class
----------.
----------.

=======================================================================

But this created problems since both set of common classes would have the exact same names etc.. in both war files. So I decided to compile the common package as a jar file and dropped it in WEB-INF/lib in each of the war files and now my war file looks like

============================================================================

app[12].war/
-----web.xml
-----app specific classes (.class files like)
-----appClass1.class
-----appClass2.class etc..
-----WEB-INF/
----------lib/
----------myPackage.jar (this is now a jar package)
----------myPackage/
---------------classes belonging to the common package like
---------------common_class1.class
---------------common_class2.class
---------------.
---------------.

============================================================================

But now my app specific classes which need to access class files withing myPackage.jar throw java.lang.ClassNotFoundException Exception.

I Googled for 3-4 frustrating hours but nothing addressed this particular problem. I'm probably doing something outrageously wrong. Can anybody smart enough please help me out?

PS: I'm deploying my wars in JBOSS 4.2.3

Thanks a ton. ~Manoj

Answer 1

JBoss has its own version-dependent peculiarities when it comes to classloading. These links might help you:

• http://www.jboss.org/community/wiki/ClassLoadingConfiguration
• http://www.devx.com/tips/Tip/29164
• http://www.jboss.org/community/wiki/JBossClassLoadingUseCases

But if both your WARs require the same version of the common package, you could put the JAR for that package into the relevant server config's lib folder (e.g. server/default/lib) instead of having it in the WAR files.