code: public static <E> void swap(E[] array1, E[] array2, int index) {
          TrivialSwap.swap(array1, index, array2, index);
      }
docs: Swap the elements of two arrays at the same position
  
  @param <E> the type of elements in this list.
  
  @param array1 one of the arrays that will have one of its values swapped.
  @param array2 the other array that will have one of its values swapped.
  @param index the index of the arrays that will have their values swapped.