code: public <T> void add(List<T> list, int index, T value) {
          list.add(index, value);
      }
docs: Insert the given value to the given list at the given index. This will
  insert the value at the index shifting the elements accordingly.
  
  @param <T> The component type of the list
  
  @param list The list to add to
  @param index The index to add at
  @param value The value to add
  
  @see List#add(int, Object)