code: public static void swap(byte[] byteArray1, int array1Index, byte[] byteArray2, int array2Index) {
          if(byteArray1[array1Index] != byteArray2[array2Index]) {
              byte hold = byteArray1[array1Index];
              byteArray1[array1Index] = byteArray2[array2Index];
              byteArray2[array2Index] = hold;
          }
          
      }
docs: Swap the elements of two byte arrays at the specified positions.
  
  @param byteArray1 one of the arrays that will have one of its values swapped.
  @param array1Index the index of the first array that will be swapped.
  @param byteArray2 the other array that will have one of its values swapped.
  @param array2Index the index of the second array that will be swapped.