code: private static int[] toIntArray(List<Integer> list) {
  		int[] array = new int[list.size()];
  		int i = 0;
  		for (Integer intObj : list) {
  			array[i++] = toInt(intObj);
  		}
  		return array;
  	}
docs: Converts an {@link Integer} list to an int array. Null values are
  converted to zero.
  @param list the {@link Integer} list
  @return the int array