code: @Benchmark long charsToMask(int reps) {
      /*
       * Comparing results we see a far more realistic sounding result whereby
       * using a bit mask is a little over 4x faster than using BitSet.
       */
      long bitMask = 0;
      for (int i = 0; i < reps; i++) {
        for (int n = 0; n < bitString.length; n++) {
          long m = 1 << n;
          if (bitString[n] == '1') {
            bitMask |= m;
          } else {
            bitMask &= ~m;
          }
        }
      }
      return bitMask;
    }
docs: This benchmark parses a char[] of 1's and 0's into a bit mask. Results from
  this benchmark should be comparable with those from
  {@link #charsToBitSet(int)}.