Yes, you can use request headers to get IP geolocation.
https://developers.google.com/appengine/docs/java/runtime#Request_Headers
The country of the X-AppEngine-Country from which the request originated. ISO 3166-1 alpha-2 country code. App Engine determines this code from the client's IP address.
, , X-AppEngine-Region, X-AppEngine-City X-AppEngine-CityLatLong
, sdk.