code: @Override
    public boolean addAll(int index, Collection<? extends Float> c) {
      if (index < 0 || index > size) {
        throw new IndexOutOfBoundsException();
      }
      ensureCapacity(size + c.size());
      size += c.size();
      for (int i = size + c.size() - 1, j = size - 1; j >= index; i--, j--) {
        elements[i] = elements[j];
      }
      for (float e : c) {
        elements[index++] = e;
      }
      return c.size() > 0;
    }
docs: /*
  (non-Javadoc)
  
  @see java.util.AbstractList#addAll(int, java.util.Collection)