Dynamic array creation

Hi all... here's a good one for you...

I have a situation where I have some bean, and I need to populate an
array field in it... here's the problem... I do not know the element
type of the array before runtime.

Now, I've been planning on using Commons Beanutils, since the rest of
this particular app does (it's doing a lot of introspection of the
beans and such).

So, here's the question... can anyone figure out a way to dynamically
create an array at runtime?  What I mean is, I want to do the
followig:

PropertyUtils.setProperty(obj, fieldName,
((List)fieldValues).toArray());

So, I want to set the field named by fieldName on the bean instance
referenced by obj, and I want to do it by taking the fieldValues List
and converting it to an array.  Now, I can do:

PropertyUtils.setProperty(obj, fieldName,
((List)fieldValues).toArray(new String[0]));

...and that's great, except that I don't know until runtime that the
field of the bean is of type String, it could be anything else.  So,
how can I dynamically do the equivalent of the new String[0] is really
the question?

FYI, I don't really care if this is done with Beanutils, but I think
that's probably the logical course of action.  Any ideas?  Thanks all!