toJson method
Implementation
Map<String, dynamic> toJson() {
final Map<String, dynamic> json = <String, dynamic>{};
json['mass'] = mass;
json['height'] = height;
json['length'] = length;
json['width'] = width;
json['axleLoad'] = axleLoad;
json['maxSpeed'] = maxSpeed;
json['fuel'] = fuel.id;
return json;
}