Object Technology Solutions India Graduate Engineer interview questions

i faced 4 rounds to get job in OTSI 1)Written Test On Logical Programming it is held at Naresh IT(hyderabad).there asked two programs one from logical's another from Spring Related(singleton design pattern) 2)Written Test it is held at OTSI(Hyderabad). they asked 30 questions(aptitude,core java,data base,networking,spring). 3)Face to Face Technical Round Interviewer asked questions on core java concepts(collections,oops,multi-threading), brief description about project what i mentioned in resume