Array to Collection: Optimized code

Question

Is there a better way of achieving this?

public static List toList(String[] array) {

    List list = new ArrayList(array.length);

          


        

Answer 1

Arrays.asList(array)

Arrays uses new ArrayList(array). But this is not the java.util.ArrayList. It's very similar though. Note that this constructor takes the array and places it as the backing array of the list. So it is O(1).

In case you already have the list created, Collections.addAll(list, array), but that's less efficient.

Update: Thus your Collections.addAll(list, array) becomes a good option. A wrapper of it is guava's Lists.newArrayList(array).