public void persistIncidentTypes() {
   JSONArray jsonIncidentTypes = new JSONArray();
   for (IncidentType incidentType : incidentTypes) {
     jsonIncidentTypes.add(incidentType.jsonify());
   }
   json.put("incidentTypes", jsonIncidentTypes);
 }
 public IncidentType getIncidentType(int id) {
   for (IncidentType type : incidentTypes) {
     if (type.getId() == id) {
       return type;
     }
   }
   return null;
 }
 private void restoreIncidentTypes() {
   JSONArray jsonIncidentTypes = (JSONArray) json.get("incidentTypes");
   int size = jsonIncidentTypes.size();
   for (int i = 0; i < size; ++i) {
     JSONObject jsonIncidentType = (JSONObject) jsonIncidentTypes.get(i);
     JSONArray jsonRequiredVehicles = (JSONArray) jsonIncidentType.get("requiredVehicleTypes");
     List<VehicleType> requiredVehicles = getVehicleTypesFromJSON(jsonRequiredVehicles);
     IncidentType incidentType = IncidentType.createFromJSON(jsonIncidentType, requiredVehicles);
     incidentTypes.add(incidentType);
   }
 }