### Question:
Ipv6Range extends AbstractIpRange<Ipv6, Ipv6Range> { @Override public BigInteger size() { return (end().value().subtract(start().value())).add(ONE); } protected  Ipv6Range(Ipv6 start, Ipv6 end); static Ipv6RangeBuilder from(Ipv6 from); static Ipv6RangeBuilder from(BigInteger from); static Ipv6RangeBuilder from(String from); static Ipv6Range parse(String range); static Ipv6Range parseCidr(String cidrString); static Ipv6Range parseDecimalNotation(String range); @Override BigInteger size();  }### Answer:
@Test public void testSize() { assertEquals(ONE, ip1.asRange().size()); assertEquals(Ipv6.MAXIMUM_VALUE.add(ONE), Ipv6Range.from(FIRST_IPV6_ADDRESS).to(LAST_IPV6_ADDRESS).size()); }