it is just a pure client side behaviour. Why you are looking for JSF component that does this simple thing?
Why am I looking for a JSF component that does this?
There are a couple of answers to this...
1: I am a bit of a newbie at this, and, well, that says a lot :-)
3: I am using facelets templating, and in the 'child' component I want to use a rollover image... the current example is for a navigation bar.
I am not sure yet which pages will have this navigation bar, and often the pages that would have it would be layered quite deep with templates...
Therefore I don't really know yet which top level templates... the ones with the html and head tags... would be getting rollover images eventually.
I could go and update all the top level templates to include rollover image functionality, just in case a component might get inserted that may use a rollover images... but it just feels a bit strange doing this.
Does this make any sense?
So there are a couple of reasons why I thought it would be nice if there was an image swap/rollover component (and thought there might be one somewhere that I missed).
But point 1 really comes into play... I am not really sure on the best way to do things (yet) :-)