DirectionsJSONParser.java

package com.nexchanges.hailyo.GoogleMapSupport;

/**
 * Created by TP on 06/08/15.
 */
    import java.util.ArrayList;
    import java.util.HashMap;
    import java.util.List;

    import org.json.JSONArray;
    import org.json.JSONException;
    import org.json.JSONObject;

    import com.google.android.gms.maps.model.LatLng;

    public class DirectionsJSONParser {

        public List<List<HashMap<String,String>>> parse(JSONObject jObject)
        {
            List<List<HashMap<String, String>>> routes = new ArrayList<List<HashMap<String,String>>>() ;
            JSONArray jRoutes = null;
            JSONArray jLegs = null;
            JSONArray jSteps = null;
            JSONObject jDistance = null;
            JSONObject jDuration = null;

            try {

                jRoutes = jObject.getJSONArray("routes");

                /** Traversing all routes */
                for(int i=0;i<jRoutes.length();i++){
                    jLegs = ( (JSONObject)jRoutes.get(i)).getJSONArray("legs");

                    List<HashMap<String, String>> path = new ArrayList<HashMap<String, String>>();

                    /** Traversing all legs */
                    for(int j=0;j<jLegs.length();j++){

                        /** Getting distance from the json data */
                        jDistance = ((JSONObject) jLegs.get(j)).getJSONObject("distance");
                        HashMap<String, String> hmDistance = new HashMap<String, String>();
                        hmDistance.put("distance", jDistance.getString("text"));

                        /** Getting duration from the json data */
                        jDuration = ((JSONObject) jLegs.get(j)).getJSONObject("duration");
                        HashMap<String, String> hmDuration = new HashMap<String, String>();
                        hmDuration.put("duration", jDuration.getString("text"));

                        /** Adding distance object to the path */
                        path.add(hmDistance);

                        /** Adding duration object to the path */
                        path.add(hmDuration);

                        jSteps = ( (JSONObject)jLegs.get(j)).getJSONArray("steps");

                        /** Traversing all steps */
                        for(int k=0;k<jSteps.length();k++){
                            String polyline = "";
                            polyline = (String)((JSONObject)((JSONObject)jSteps.get(k)).get("polyline")).get("points");
                            List<LatLng> list = decodePoly(polyline);

                            /** Traversing all points */
                            for(int l=0;l<list.size();l++){
                                HashMap<String, String> hm = new HashMap<String, String>();
                                hm.put("lat", Double.toString(((LatLng)list.get(l)).latitude) );
                                hm.put("lng", Double.toString(((LatLng)list.get(l)).longitude) );
                                path.add(hm);
                            }
                        }
                    }
                    routes.add(path);
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }catch (Exception e){
            }
            return routes;
        }

        /**
         * Method to decode polyline points
         * Courtesy : jeffreysambells.com/2010/05/27/decoding-polylines-from-google-maps-direction-api-with-java
         * */
        private List<LatLng> decodePoly(String encoded) {

            List<LatLng> poly = new ArrayList<LatLng>();
            int index = 0, len = encoded.length();
            int lat = 0, lng = 0;

            while (index < len) {
                int b, shift = 0, result = 0;
                do {
                    b = encoded.charAt(index++) - 63;
                    result |= (b & 0x1f) << shift;
                    shift += 5;
                } while (b >= 0x20);
                int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
                lat += dlat;

                shift = 0;
                result = 0;
                do {
                    b = encoded.charAt(index++) - 63;
                    result |= (b & 0x1f) << shift;
                    shift += 5;
                } while (b >= 0x20);
                int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
                lng += dlng;

                LatLng p = new LatLng((((double) lat / 1E5)),
                        (((double) lng / 1E5)));
                poly.add(p);
            }
            return poly;
        }
    }