Very informal. More talk about personality than about Spring MVC, etc. It seems panel tries to understand your approach more than syntax. There were some algorithmic questions. There were quite a few questions on work ethic. A lot of discussion on my home country - travels, etc. :-) One thing I can suggest is that the interview committee just seems to pick one thing/project on your resume and drill down into it. So, if you put something on it, just make sure you really know what it was in detail. If you were part of a team, then just put what you specifically know very well.