Array to Collection: Optimized code

What do you mean by better way:

more readable:

List<String> list = new ArrayList<String>(Arrays.asList(array));

less memory consumption, and maybe faster (but definitely not thread safe):

public static List<String> toList(String[] array) {
    if (array==null) {
       return new ArrayList(0);
    } else {
       int size = array.length;
       List<String> list = new ArrayList(size);
       for(int i = 0; i < size; i++) {
          list.add(array[i]);
       }
       return list;
    }
}

Btw: here is a bug in your first example:

array.length will raise a null pointer exception if array is null, so the check if (array!=null) must be done first.

Leave a Comment