Cannot instantiate the type Set

Question

I am trying to create a Set of Strings which is filled with the keys from a Hashtable so a for-each loop can iterate through the Set and put defaults in a Hashtable. I am st

Answer 1

Set is an interface. You cannot instantiate an interface, only classes which implement that interface.

The interface specifies behaviour, and that behaviour can be implemented in different ways by different types. If you think about it like that, it makes no sense to instantiate an interface because it's specifying what a thing must do, not how it does it.