code: public boolean contains(final BinaryString substring) {
  		ensureMaterialized();
  		substring.ensureMaterialized();
  		if (substring.sizeInBytes == 0) {
  			return true;
  		}
  		int find = SegmentsUtil.find(
  			segments, offset, sizeInBytes,
  			substring.segments, substring.offset, substring.sizeInBytes);
  		return find != -1;
  	}
docs: Returns whether this contains `substring` or not.
  Same to like '%substring%'.