I work in a medium to small team ( 10 people ) developing and supporting several web enterprise applications. 

We have a dozen of them built with a house-made framework with asp-classic working against ms-sql server.

We are evaluating the migration to a new development stack. 

We'd like it to be open (free) and simple.

I've been looking around the java web frameworks, but all of them seem to be extremely overbloated for our needs (with the possible exception of <http://www.playframework.org/>, which I couldn't study yet...)

We are thinking about porting our own framework to this new stack, rather than adopting a whole new stack that we are unaware of ...

so far now, we though about the following possibilities

* plain java - jsp - jsf
* groovy - gsp (no grails at all)
* jruby (no rails at all)

we feel really comfortable working with dynamic languages (well, as dynamic as classic asp can be) and with a lean and understandable framework...

I see no small and simple web frameworks for java, like there are for php or ruby...

I really like groovy, but I see no web implementations outside of grails... Besides the language documentation doesn't seem to be quite complete (I might be looking in the wrong place, perhaps)

php could be an option, but I think it would be hard to advocate for it in my current work...

any other option, advice, pros and cons?

thanks a lot

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some related link [Can anyone recommend a simple Java web-app framework?](https://stackoverflow.com/questions/116978/can-anyone-recommend-a-simple-java-web-app-framework)