Jar files not in WEB-INF/lib (custom ClassLoader?)

Question

I need to use classes in my JSP that do not come from a JAR file in the standard location. Sounds like I "simply" need to extend the ClassLoader used by the app server for loading the JSP. Is there any way of doing that?
Example: my.jsp
<h1>Hi</h1>
<%
FOO x = new FOO(); // code from a non-standard place
ClassLoader cl = getClass().getClassLoader();
%>
I cannot put FOO.class into WEB-INF/lib or any of the standard places. Ideally I'd like to give the ClassLoader (cl above) a different (custom) parent ClassLoader which would know how to resolve FOO.class.
I've poured over docs and Google and WebSphere and the Tomcat source code. Is this request of mine really so outrageous? I'm about the give up. What good are custom classloaders if one can't use them?

Answer 1

You are essentially making the argument "All that Java
needs is a URLClassLoader, and no one has any need for
any custom ClassLoaders". (After all, that's all that
I seem to have in a JSP context, with a list of
hard-coded URLs into that URLClassLoader ...)
Do a Google search on "custom ClassLoader" and you
will find lots of reasons why people want to have
custom ClassLoaders, such as ones that don't use any
JAR or .class files ... which would qualify as why I
can't put them into a certain place ...To be fair to duffymo, that is not how I read his argument. I read it as:
"Sometimes we try to do things the hard way. If we sit back and rethink the problem, an easier solution might come about."
I think this is a good opportunity to explain why you can not use the normal class loader heirarchy. You have no JARs and no .class files? Then where are you getting the class definitions? If you explain enough so that we might understand the problem:
1) we might be able to come up with a solution or
2) you might see a different approach before you are even done explaining
#2 has happened to me more times then I can count. I sit down formulating a question for the forums, make sure I include enough detail to explain my problem. And by the time I am done I have a new (usually simpler) approach to solving the problem.
Or you could sit and defend your first approach without providing any context and accomplish nothing. So its up to you.