code: @Override
      public JSONObject toJSON() throws JSONException {
          JSONObject json = super.toJSON();
  
          JSONArray features = new JSONArray();
          for (Feature feature : this.mFeatures) {
              features.put(feature.toJSON());
          }
  
          json.put(JSON_FEATURES, features);
  
          return json;
      }
docs: {@inheritDoc}