code: @Override
      public Object[] toArray() {
          Object[] elements = getArray();
          return Arrays.copyOf(elements, elements.length);
      }
docs: Returns an array containing all of the elements in this list
  in proper sequence (from first to last element).
  
  <p>The returned array will be "safe" in that no references to it are
  maintained by this list. (In other words, this method must allocate
  a new array). The caller is thus free to modify the returned array.
  
  <p>This method acts as bridge between array-based and collection-based
  APIs.
  
  @return an array containing all the elements in this list