Haven't tried it myself, but I think
http://www.playframework.org/
has a lot of potential...
coming from php and classic asp, it's the first java web framework that sounds promising to me....
Edit by original question asker - 2011-06-09
Just wanted to provide an update.
I went with Play and it was exactly what I asked for. It requires very little configuration, and just works out of the box. It is unusual in that it eschews some common Java best-practices in favor of keeping things as simple as possible.
In particular, it makes heavy use of static methods, and even does some introspection on the names of variables passed to methods, something not supported by the Java reflection API.
Play's attitude is that its first goal is being a useful web framework, and sticking to common Java best-practices and idioms is secondary to that. This approach makes sense to me, but Java purists may not like it, and would be better-off with Apache Wicket.
In summary, if you want to build a web-app with convenience and simplicity comparable to a framework like Ruby on Rails, but in Java and with the benefit of Java's tooling (eg. Eclipse), then Play Framework is a great choice.