code: public void forEach(final IntConsumer action) {
  		requireNonNull(action);
  
  		final int size = _size;
  		for (int i = 0; i < size; ++i) {
  			action.accept(_data[i]);
  		}
  	}
docs: Performs the given action for each element of the list.
  
  @param action the action to be performed for each element
  @throws NullPointerException if the specified action is {@code null}