Question

I have a TreeSet which contains > 100k objects.
I have another method which requires ArrayList as an param.

Is there any way I can accomplish this without iterating whole TreeSet and then adding each object manually to ArrayList ?

Answer 1

How about this:

new ArrayList<T>(set);

For Java 7 and later, this can be simplified, as type arguments <T> can be replaced with diamond type <>:

new ArrayList<>(set);