Hello. We have RoR application and we are planning to make js interface(extjs or closure) in new version. Is it possible to use GWT with RoR?
I'm not that familiar with GWT but I guess in theory it's possible to use GWT cross compile Java into JavaScript which is then used within a Rails application. It sounds pretty cumbersome though.
You can, but you won't have the nice RPC mechanism available with java based servers. You'll probably have to use RequestBuilder class to pass data to the server & back.
Yes, using GWT with RoR is perfectly possible. Client server communication will be by JSON, which RoR can easily produce. GWT works best when you're creating a client side app in HTML/JavaScript/CSS, if you want progressive enhancement of an existing HTML UI jQuery etc. might be a better choice.
The http://code.google.com/p/gwt-rails/ project is intended to provide easy to use RPC between RoR backend, and GWT UI.