Force Java runtime to use Jar in NSF instead of Jar on server of same name for XPages application

Question

I am trying to tackle a persistent ClassNotFoundException. We have an application specific jar that calls a shared commons jar, and uses reflection create an object that we specify in an XML file. This is where it fails.

The application specific jar resides in my NSF. The commons jar resides on the server. I wish to keep the jars in the NSF, because I will be replacing them frequently and don't have access to the server directories, even in Unit.

We put the application jar in the same package as the commons and this didn't help. My suspicion is that the server jar cannot find the application jar. The application jar successfully calls the commons jar, so it is working in that direction.

I tried putting a copy of the commons jar in the NSF, and this didn't help. I think it is still running the server jar first. Jars have same name.

My question is: How do I force the Domino Server runtime to use the application's 'commons' jar instead of the server's 'commons' jar? The thinking being that the local commons jar will find the class of the application jar in the same package, and I can get past this exception.

UPDATE: This process runs when run from a jUnit test, and when a main method is created.

Answer 1

The key is going to be identifying if it's failing because of a security exception or just not finding the jar. If it hits a security exception loading the jar, it just gives that ClassNotFoundException. That can be because it's using the same ClassLoader as the XPpages runtime and was the problem I hit with apache.commons.lang.

If a jar is likely to change regularly and you want it from multiple NSFs, but don't have access to the server, the best option is to create an OSGi plugin (aka Extension Library). This will overcome most security exceptions as well as using a different classloader.

Put it in WebContent\lib, then right-click on it and choose Build Path > Add to Build Path. It will then use a different ClassLoader. See the comments on this blog post http://www.intec.co.uk/how-to-add-in-built-java-packages/. The lib folder is added by default in R9. You do need to add it to the build path, then it jumps into a Referenced Libraries folder.