/**
* Parses a url pointing to a Google JSON object to a Route object.
*
* @return a Route object based on the JSON object.
*/
public Route parse() {
// turn the stream into a string
final String result = convertStreamToString(this.getInputStream());
// Create an empty route
final Route route = new Route();
// Create an empty segment
final Segment segment = new Segment();
try {
// Tranform the string into a json object
final JSONObject json = new JSONObject(result);
// Get the route object
final JSONObject jsonRoute = json.getJSONArray("routes").getJSONObject(0);
// Get the leg, only one leg as we don't support waypoints
final JSONObject leg = jsonRoute.getJSONArray("legs").getJSONObject(0);
// Get the steps for this leg
final JSONArray steps = leg.getJSONArray("steps");
// Number of steps for use in for loop
final int numSteps = steps.length();
// Set the name of this route using the start & end addresses
route.setName(leg.getString("start_address") + " to " + leg.getString("end_address"));
// Get google's copyright notice (tos requirement)
route.setCopyright(jsonRoute.getString("copyrights"));
// Get the total length of the route.
route.setLength(leg.getJSONObject("distance").getInt("value"));
// Get any warnings provided (tos requirement)
if (!jsonRoute.getJSONArray("warnings").isNull(0)) {
route.setWarning(jsonRoute.getJSONArray("warnings").getString(0));
}
/*
* Loop through the steps, creating a segment for each one and
* decoding any polylines found as we go to add to the route
* object's map array. Using an explicit for loop because it is
* faster!
*/
for (int i = 0; i < numSteps; i++) {
// Get the individual step
final JSONObject step = steps.getJSONObject(i);
// Get the start position for this step and set it on the
// segment
final JSONObject start = step.getJSONObject("start_location");
final GeoPoint position =
new GeoPoint(
(int) (start.getDouble("lat") * 1E6), (int) (start.getDouble("lng") * 1E6));
segment.setPoint(position);
// Set the length of this segment in metres
final int length = step.getJSONObject("distance").getInt("value");
distance += length;
segment.setLength(length);
segment.setDistance(distance / 1000);
// Strip html from google directions and set as turn instruction
segment.setInstruction(step.getString("html_instructions").replaceAll("<(.*?)*>", ""));
// Retrieve & decode this segment's polyline and add it to the
// route.
route.addPoints(decodePolyLine(step.getJSONObject("polyline").getString("points")));
// Push a copy of the segment to the route
route.addSegment(segment.copy());
}
} catch (JSONException e) {
if (DEBUG.ON) {
Log.e(e.getMessage(), "Google JSON Parser - " + feedUrl);
}
}
return route;
}
