Wipro Technical Lead interview questions

I received an offer from wipro for .Net lead requirement where they released my offer letter on their embark portal. After receiving the offer letter I resigned from my existing organization and looked forward to join wipro in Hyderabad. Just 15 days before my DOJ the recruiter called me and stated that they cannot pursue with the offer as the business demand has changed. I requested them that it's unethical to deny from what has been offered considering I am looking forward to join them and have already put down my resignation in the existing organization. The recruiter replied back stating that she didn't have control on such decisions as they decision is from management.

There was 3 rounds. Intervive process is good overall. Nice people.Managers are good. Good to work. Most of the questions are from spring, collections,. Exception handling.. hibernate and design patterns etc