https://docs.oracle.com/javase/jp/9/docs/api/java/net/Inet6Address.html
Inet6Address (Java SE 9 & JDK 9 )
java sejdk
https://developers.google.com/j2objc/javadoc/jre/reference/java/net/Inet6Address
Inet6Address | J2ObjC | Google for Developers
googledevelopers