Why Collection.toArray(T[]) doesn't take an E[] instead

Question

The toArray method (lets pick the implementation in java.util.ArrayList) is the following:

class ArrayList ....{
    public  T         


        

Answer 1

The point of the is if the array desired is of a base class of E. For example if E is HashMap but the desired array was Map[]. If toArray were locked down to E this would not be possible.

This type of thing is not needed in generic collections / types due to type-erasure. But there is no type-erasure with arrays so the type of the array can be very important.