Coforge interview question

1)TreeMap internal implementation—>data structure Red black tree datastructure Treeset uses treemap datastructure 2)How to get the unique values in Map<List<Employee>> 3)CallableStatement 4)2 LinkedList …it moved one node to another node …how to find it will move to another node 5)In Production ,how to check rest API is up or not?-----spring boot actuators 6)GC- I want to call GC ..how to do that 7)Spring bean life cycle