Hello,

After using Hibernate for a while I noticed that whenever it has problems with missing libraries (jars), it throws NoClassDefFoundError (usually in CGLIBLazyInitializer.getProxyFactory method). The thing is it never says what is it exactly that it's missing.
Is there a way of finding out which out of the many jar files included with Hibernate is needed? Saying 'NoClassDefFoundError' without specifying which class is missing is not helping at all.
I'd appreciate any help on this subject.

Bratek

try to make your logging more verbose (debug). This should give you a better hint on the missing class.

Regards Sebastian

I tried to put log4j.properties in class path (containing single entry: log4j.logger.org.hibernate=debug), but that did not cause any new information to be printed in the log files (I'm running my code in a servlet, so I put log4j.properties in WEB-INF/classes folder). Is there any other way I can get the missing class/jar info to print in log files?

Bratek

I do not know your application server. In JBoss which includes Tomcat you can set the logging to debug in the log4jxml in the conf directory.

There should be something like this for your server.

Just an idea but is asm missing?

Regards Sebastian

Yes, asm is there, same as asm-attrs. I'm using Sun App Server (formerly Sun One), the one that comes with J2EE 1.4.
I'll keep looking, if I find an answer I will post it here.
Thanks,

Bratek

OK, so the problem was related to deployment procedure. If you're using Sun Server, don't use this option:

Specify a package file or a directory path that must be accessible from the server.

(This is on the Deploy Enterprise Application page of the admin console.)

Use this option:

Specify a package file to upload to the Application Server.

For some reason Hibernate classes could not be located in classpath. So now the Hibernate code kind of works (query results come back from db), but not entirely (updates don't work). I'm getting a new error now (Caused by: java.lang.NullPointerException at org.hibernate.tuple.AbstractEntityTuplizer.createProxy(AbstractEntityTuplizer.java:372)
).
But that will be a separate post.

Bratek

OK, I found a solution. On Russian Hibernate news group someone helpfully posted those two lines:

permission java.lang.RuntimePermission "getProtectionDomain";
permission java.lang.reflect.ReflectPermission "suppressAccessChecks";

If you put that in your server.policy file (Sun/AppServer/domains/domain1/config, under grant { ... };) your Hibernate app should stop getting those errors.
Of course all the required libraries (jars) must be present (I put them in WEB-INF/lib, and both servlets and EJBs have access to them).

So this concludes my 3 day hunt for an answer. And here's a short quiz:

Given the following data:

If Hibernate is missing required libraries, it throws NoClassDefFoundError.
If Hibernate is missing permissions, it throws NoClassDefFoundError.

Figure out the correct answer to the following question:

If your app server catches on fire, Hibernate throws ... ?


Bratek

PS. Big thank you to the fellow who posted the correct answer on Russian forum.