Infosys interview question

1)Explain current domain and technical stack 2)How do manage exceptions in spring boot project 3)How to submit exceptions from child to parent 4)Spring boot profiling how to setup 5)Concurrent modification exception 6)Optional class 7)Difference between @RestController and @Controller 8)Hashmap vs Hashtable 9)How do you use polymorphism in your project 10)When to use interface and when to use abstract class 11)Fail fast and fail safe 12)Explain flow for the endpoint getAllEmployee () method