code: public static void swap(long[] longArray1, long[] longArray2, int index) {
          TrivialSwap.swap(longArray1, index, longArray2, index);
      }
docs: Swap the elements of two long arrays at the same position
  
  @param longArray1 one of the arrays that will have one of its values swapped.
  @param longArray2 the other array that will have one of its values swapped.
  @param index the index of the arrays that will have their values swapped.