public class GeofenceTransitionsIntentService extends IntentService {
 ...
  protected void onHandleIntent(Intent intent) {
    GeofencingEvent geofencingEvent = GeofencingEvent.fromIntent(intent);
    if (geofencingEvent.hasError()) {
        String errorMessage = GeofenceErrorMessages.getErrorString(this,
                geofencingEvent.getErrorCode());
        Log.e(TAG, errorMessage);
        return;
    }

    // Tipo di transition (ENTER / EXIT)
    int geofenceTransition = geofencingEvent.getGeofenceTransition();

    // Verifica che la transizione sia quella richiesta
    if (geofenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER ||
            geofenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT) {

        // Prelevo l'array delle geofence ricevute dall'IntentService
        List triggeringGeofences = geofencingEvent.getTriggeringGeofences();

        // Get the transition details as a String.
        String geofenceTransitionDetails = getGeofenceTransitionDetails(
                this,
                geofenceTransition,
                triggeringGeofences
        );

        //TODO: logica legata alla richiesta, es. mostro notifica
        Log.i(TAG, geofenceTransitionDetails);
    } else {
        // Log the error.
        Log.e(TAG, getString(R.string.geofence_transition_invalid_type,
                geofenceTransition));
    }
  }