Basic core java questioning and collection and multithreding ,stream api coding question for duplicate number and sum of number and non repeting characters and functional interface lamda expression ,default and static method in interface explain,private method in functional interfaces, name of the functional interfaces

The interview was scheduled via a Consultancy Company. The interview questions were moderate level. The interviewers were polite I got the offer but it was a slight cross profile for me so I had to let it go.