It was the worst experience ever. If you are wrong then they laugh at you. They assume that we are Google, and we have all question's answers. They even ask questions from Google. Sounds funny. Given the program to add 2 numbers using the functional interface, I used lambda for the same, the interviewer said this will not give an answer. Then I used IntelliJ and wrote the code and got the output. I said the default scope of bean in singleton in spring boot, and he laughed and said Check Google.