code: @Pure
  	public BusItineraryHalt getNearestBusHalt(double x, double y) {
  		double distance = Double.POSITIVE_INFINITY;
  		BusItineraryHalt besthalt = null;
  		double dist;
  
  		for (final BusItineraryHalt halt : this.validHalts) {
  			dist = halt.distance(x, y);
  			if (dist < distance) {
  				distance = dist;
  				besthalt = halt;
  			}
  		}
  
  		return besthalt;
  	}
docs: Replies the nearest bus halt to the given point.
  
  @param x x coordinate.
  @param y y coordinate.
  @return the nearest bus halt or <code>null</code> if none was found.