Question

Possible Duplicate:
How to create ArrayList (ArrayList<T>) from array (T[]) in Java

How to implement this method:

List<Integer> toList(int[] integers) {
    ???
    //return Arrays.asList(integers); doesn't work
}

Answer 1

There’s probably a built-in method to do it somewhere* (as you note, Arrays.asList won’t work as it expects an Integer[] rather than an int[]).

I don’t know the Java libraries well enough to tell you where that is. But writing your own is quite simple:

public static List<Integer> createList(int[] array) {
    List<Integer> list = new ArrayList<Integer>(array.length);
    for (int i = 0; i < array.length; ++i) {
        list.add(array[i]);
    }
    return list;
}

Obviously one downside of this is that you can’t do it generically. You’ll have to write a separate createList method for each autoboxed primitive type you want.

_{*And if there isn’t, I really wonder why not.}