Sorted copy construction for ArrayList

Question

I have an ArrayList.
How can I instantiate a new List with the same data but sorted?
I thought about the following:

1. Use the ArrayList copy constructor and then use Collections.sort
2. Use a TreeSet

For option (1) there is the extra overhead of copying the elements and then sorting.
For option (2) duplicates will be removed.
What is the best way for this?

Answer 1

If you can use third-party libraries, then with Guava this is just

List<Foo> sortedCopy = Ordering.from(comparator).sortedCopy(list);

(Disclosure: I contribute to Guava.)