code: protected LocationCoordinates getLocationMessage(MessageEnvelope envelope) {
  		if (envelope != null
  				&& envelope.getMessage() != null
  				&& envelope.getMessage().getAttachments() != null
  				&& envelope.getMessage().getAttachments().get(0) != null
  				&& envelope.getMessage().getAttachments().get(0).getPayload() != null
  				&& envelope.getMessage().getAttachments().get(0).getPayload() instanceof QuickReplyLocationPayload) {
  
  			QuickReplyLocationPayload payload = (QuickReplyLocationPayload) envelope
  					.getMessage().getAttachments().get(0).getPayload();
  
  			return payload.getCoordinates();
  		}
  		return null;
  	}
docs: Retrieves the location from an envelope. It return nulls if none was
  retrieved.
  
  @param envelope
  the message envelope
  @return a {@link LocationCoordinates} containing the coordinates that the
  user sets from the quick reply location payload.