Java tutorial
/* * Copyright (C) 2014 Saurabh Rane * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.geoservicesapi.services; import java.io.BufferedReader; import java.io.InputStream; import java.io.InputStreamReader; import java.net.URL; import java.nio.charset.Charset; import org.json.JSONObject; import org.json.JSONArray; /** * DirectionsServices is a class for consuming directions services using MapQuest Directions API. * * @author Saurabh Rane * @version 2014-07-24 */ public class DirectionsServices { private String mapQuestApiKey; /** * Construct a DirectionsServices with your mapQuest api key. * * @param mapQuestApiKey * Your api key for mapQuest api. */ public DirectionsServices(String mapQuestApiKey) { this.mapQuestApiKey = mapQuestApiKey; } /** * Get the route from a source to a destination. * * @param source * A key string of the format "lat, lng". * @param destination * A key string of the format "lat, lng". * @return The JSONObject associated with the route. */ public JSONObject getRoute(String source, String destination) { JSONObject result = new JSONObject(); if (source == null) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are missing in request."); error.put("id", "MISSING_PARAMETER"); error.put("field", "source"); result.put("error", error); } else if (destination == null) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are missing in request."); error.put("id", "MISSING_PARAMETER"); error.put("field", "destination"); result.put("error", error); } else if (!source.contains(",")) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are invlid in request."); error.put("id", "INVALID_PARAMETER"); error.put("field", "source"); result.put("error", error); } else if (!destination.contains(",")) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are invlid in request."); error.put("id", "INVALID_PARAMETER"); error.put("field", "destination"); result.put("error", error); } else { String slat = "", slng = "", dlat = "", dlng = ""; String[] src = source.split(","); String[] dest = destination.split(","); if (!source.endsWith(",") && !source.startsWith(",")) { slat = src[0]; slng = src[1]; } if (!destination.endsWith(",") && !destination.startsWith(",")) { dlat = dest[0]; dlng = dest[1]; } if (slat.trim().equals("") || slng.trim().equals("")) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are invlid in request."); error.put("id", "INVALID_PARAMETER"); error.put("field", "source"); result.put("error", error); } else if (dlat.trim().equals("") || dlng.trim().equals("")) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are invlid in request."); error.put("id", "INVALID_PARAMETER"); error.put("field", "destination"); result.put("error", error); } else { String apiUrl = "http://open.mapquestapi.com/directions/v2/route?key=" + mapQuestApiKey + "&avoids=Toll%20road&from=" + slat + "," + slng + "&to=" + dlat + "," + dlng + "&routeType=fastest"; try { InputStream is = new URL(apiUrl).openStream(); BufferedReader rd = new BufferedReader(new InputStreamReader(is, Charset.forName("UTF-8"))); StringBuilder sb = new StringBuilder(); int cp; while ((cp = rd.read()) != -1) { sb.append((char) cp); } String jsonText = sb.toString(); JSONObject res = new JSONObject(jsonText); JSONObject info = (JSONObject) res.getJSONObject("info"); int statusCode = info.getInt("statuscode"); if (statusCode == 0) { JSONObject route = (JSONObject) res.getJSONObject("route"); boolean hasTollRoad = route.getBoolean("hasTollRoad"); boolean hasCountryCross = route.getBoolean("hasCountryCross"); boolean hasFerry = route.getBoolean("hasFerry"); double distance = route.getDouble("distance"); double fuelUsed = route.getDouble("fuelUsed"); String formattedTime = route.getString("formattedTime"); JSONArray legs = (JSONArray) route.getJSONArray("legs"); JSONObject steps = new JSONObject(); steps.put("hasTollRoad", hasTollRoad); steps.put("hasCountryCross", hasCountryCross); steps.put("hasFerry", hasFerry); steps.put("distance", distance); steps.put("fuelUsed", fuelUsed); steps.put("formattedTime", formattedTime); if (legs.length() > 0) { JSONObject leg = (JSONObject) legs.get(0); JSONArray maneuvers = (JSONArray) leg.getJSONArray("maneuvers"); JSONArray directions = new JSONArray(); String[] turnTypes = { "straight", "slight right", "right", "sharp right", "reverse", "sharp left", "left", "slight left", "right u-turn", "left u-turn", "right merge", "left merge", "right on ramp", "left on ramp", "right off ramp", "left off ramp", "right fork", "left fork", "straight fork", "take transit", "transfer transit", "port transit", "enter transit", "exit transit" }; for (int i = 0; i < maneuvers.length(); i++) { JSONObject maneuver = (JSONObject) maneuvers.get(i); String narrative = maneuver.getString("narrative"); String url = ""; int turnType = maneuver.getInt("turnType"); String transportMode = maneuver.getString("transportMode"); if (i != maneuvers.length() - 1) { url = maneuver.getString("mapUrl"); } String iconUrl = maneuver.getString("iconUrl"); double dis = maneuver.getDouble("distance"); String time = maneuver.getString("formattedTime"); String directionName = ""; try { directionName = maneuver.getString("directionName"); } catch (Exception ignore) { } JSONObject man = new JSONObject(); man.put("narrative", narrative); man.put("url", url); man.put("distance", dis); man.put("time", time); if (turnType == -1) { man.put("turnType", "end"); } else { man.put("turnType", turnTypes[turnType]); } man.put("transportMode", transportMode); man.put("direction", directionName); man.put("iconUrl", iconUrl); directions.put(i, man); } steps.put("directions", directions); } result.put("route", steps); } } catch (Exception e) { JSONObject error = new JSONObject(); error.put("message", "Error processing request. Try again after some time"); result.put("error", error); } } } return result; } /** * Get the mid point of a route from a source to a destination. * * @param source * A key string of the format (lat, lng). * @param destination * A key string of the format (lat, lng). * @return The JSONObject associated with the route. */ public JSONObject getMidpoint(String source, String destination) { JSONObject result = new JSONObject(); if (source == null) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are missing in request."); error.put("id", "MISSING_PARAMETER"); error.put("field", "source"); result.put("error", error); } else if (destination == null) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are missing in request."); error.put("id", "MISSING_PARAMETER"); error.put("field", "destination"); result.put("error", error); } else if (!source.contains(",")) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are invlid in request."); error.put("id", "INVALID_PARAMETER"); error.put("field", "source"); result.put("error", error); } else if (!destination.contains(",")) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are invlid in request."); error.put("id", "INVALID_PARAMETER"); error.put("field", "destination"); result.put("error", error); } else { String slat = "", slng = "", dlat = "", dlng = ""; String[] src = source.split(","); String[] dest = destination.split(","); if (!source.endsWith(",") && !source.startsWith(",")) { slat = src[0]; slng = src[1]; } if (!destination.endsWith(",") && !destination.startsWith(",")) { dlat = dest[0]; dlng = dest[1]; } if (slat.trim().equals("") || slng.trim().equals("")) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are invlid in request."); error.put("id", "INVALID_PARAMETER"); error.put("field", "source"); result.put("error", error); } else if (dlat.trim().equals("") || dlng.trim().equals("")) { JSONObject error = new JSONObject(); error.put("message", "One or more parameters are invlid in request."); error.put("id", "INVALID_PARAMETER"); error.put("field", "destination"); result.put("error", error); } else { String apiUrl = "http://open.mapquestapi.com/directions/v2/route?unit=k&key=" + mapQuestApiKey + "&avoids=Toll%20road&from=" + slat + "," + slng + "&to=" + dlat + "," + dlng + "&routeType=fastest"; try { InputStream is = new URL(apiUrl).openStream(); BufferedReader rd = new BufferedReader(new InputStreamReader(is, Charset.forName("UTF-8"))); StringBuilder sb = new StringBuilder(); int cp; while ((cp = rd.read()) != -1) { sb.append((char) cp); } String jsonText = sb.toString(); JSONObject res = new JSONObject(jsonText); JSONObject info = (JSONObject) res.getJSONObject("info"); int statusCode = info.getInt("statuscode"); if (statusCode == 0) { JSONObject route = (JSONObject) res.getJSONObject("route"); double distance = route.getDouble("distance"); double mid = distance / 2; JSONArray legs = (JSONArray) route.getJSONArray("legs"); JSONObject midpoint = new JSONObject(); if (legs.length() > 0) { JSONObject leg = (JSONObject) legs.get(0); JSONArray maneuvers = (JSONArray) leg.getJSONArray("maneuvers"); double startLat = 0, startLng = 0, endLat = 0, endLng = 0; double oldDistance = 0; double distanceTillNow = 0; int index = 0; for (; index < maneuvers.length() && distanceTillNow < mid; index++) { JSONObject maneuver = (JSONObject) maneuvers.get(index); double maneuverDistance = maneuver.getDouble("distance"); JSONObject startPoint = maneuver.getJSONObject("startPoint"); startLat = startPoint.getDouble("lat"); startLng = startPoint.getDouble("lng"); oldDistance = distanceTillNow; distanceTillNow += maneuverDistance; } JSONObject lastManeuver = new JSONObject(); if (index == maneuvers.length()) { lastManeuver = (JSONObject) maneuvers.get(index - 1); } else { lastManeuver = (JSONObject) maneuvers.get(index); } JSONObject endPoint = lastManeuver.getJSONObject("startPoint"); endLat = endPoint.getDouble("lat"); endLng = endPoint.getDouble("lng"); if (distanceTillNow < mid) { return null; } double m = (mid - oldDistance) / (distanceTillNow - oldDistance); double midLat = startLat + (endLat - startLat) * m; double midLng = startLng + (endLng - startLng) * m; midpoint.put("lat", midLat); midpoint.put("lng", midLng); } result.put("midway", midpoint); } } catch (Exception e) { JSONObject error = new JSONObject(); error.put("message", "Error processing request. Try again after some time"); result.put("error", error); } } } return result; } }