docs: public void addInt(
          @DoNotSub final int index,
          final int element)
      {
          checkIndexForAdd(index);
  
          @DoNotSub final int requiredSize = size + 1;
          ensureCapacityPrivate(requiredSize);
  
          if (index < size)
          {
              System.arraycopy(elements, index, elements, index + 1, size - index);
          }
  
          elements[index] = element;
          size++;
      }