https://docs.oracle.com/javase/jp/8/docs/api/java/net/SocketImplFactory.html
SocketImplFactory (Java Platform SE 8)
java platformse
https://developers.google.com/j2objc/javadoc/jre/reference/java/net/SocketImplFactory
SocketImplFactory | J2ObjC | Google for Developers
googledevelopers