I have a class like:
   class Car {
        private Engine engine;
        private String color;  
        private int maxspeed;
    }
and Engine class like
class Engine {
    private String fueltype;
    private String enginetype;
}  
I want to convert the Car object to JSON using Jackson with structure like
'car': {
   'color': 'red',
   'maxspeed': '200',
   'fueltype': 'diesel',
   'enginetype': 'four-stroke'
 } 
How can I do that?