用百度地图api计算两个地方的距离

/**
 * @author 距离计算
 *
 */
public class DistanceUtil {
	private static final String showLocationUrl = "http://api.map.baidu.com/geocoder/v2/?output=json&ak=RguGdBfvanKG10lrLHtUAtka&address=";
	private static final String waypointsDistanceUrl = "http://api.map.baidu.com/telematics/v3/distance?output=json&ak=RguGdBfvanKG10lrLHtUAtka&waypoints=";
	
	@SuppressWarnings("unchecked")
	public static Double twoCitysDistance(String startCityName, String endCityName){
		Double distance = 0.00;
		
		Map<String, Object> startShowLocation = JsoupTool.getJson(showLocationUrl+startCityName, null);
		Map<String, Object> startResultLocation = (Map<String, Object>) startShowLocation.get("result");
		Map<String, Object> startLocation = (Map<String, Object>) startResultLocation.get("location");
		String startLng = startLocation.get("lng").toString();
		String startLat =  startLocation.get("lat").toString();
		
		Map<String, O