code: protected static boolean isPrefixSubnet(IPAddressSegment sectionSegments[], Integer networkPrefixLength, IPAddressNetwork<?, ?, ?, ?, ?> network, boolean fullRangeOnly) {
  		int segmentCount = sectionSegments.length;
  		if(segmentCount == 0) {
  			return false;
  		}
  		IPAddressSegment seg = sectionSegments[0];
  		return ParsedAddressGrouping.isPrefixSubnet(
  				(segmentIndex) -> sectionSegments[segmentIndex].getSegmentValue(),
  				(segmentIndex) -> sectionSegments[segmentIndex].getUpperSegmentValue(),
  				segmentCount,
  				seg.getByteCount(),
  				seg.getBitCount(),
  				seg.getMaxSegmentValue(),
  				networkPrefixLength,
  				network.getPrefixConfiguration(),
  				fullRangeOnly);
  	}
docs: /*
  Starting from the first host bit according to the prefix, if the section is a sequence of zeros in both low and high values,
  followed by a sequence where low values are zero and high values are 1, then the section is a subnet prefix.
  
  Note that this includes sections where hosts are all zeros, or sections where hosts are full range of values,
  so the sequence of zeros can be empty and the sequence of where low values are zero and high values are 1 can be empty as well.
  However, if they are both empty, then this returns false, there must be at least one bit in the sequence.