import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.SettableFuture;
import java.math.BigInteger;
-import java.net.Inet4Address;
-import java.net.Inet6Address;
-import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.util.Arrays;
import java.util.Collection;