CSC Professional 1-Product Developer interview questions

I applied through Referal drive for 2 years experiance. They called me first Telephonic Round.One did telephonic round,he asked all the java related concepts especially in JVM , Threading,OOPs, Exception Handling and Internal Hash Map Implementation.This round is going on around 1 hour. Later they called me Managerial round, he asked me about what i did in previous company, project architecture etc..Then they called me another Telephonic round again java related things and Rest. Finally i got the offer letter.Its a postivie interview experience.