Switching to Android Marshmallow API, I was using org.apache.http.conn.util.InetAddressUtils for InetAddressUtils.isIPv4Address(ipAddress) in a cod
org.apache.http.conn.util.InetAddressUtils
InetAddressUtils.isIPv4Address(ipAddress)
To use this library in SDK 23 add following line in project's build.gradle file:
useLibrary 'org.apache.http.legacy'