Injection and inheritance

Question

abstract class Vehicle
{
   void collide(Vehicle v){}
}

class Car extends Vehicle
{
   @Override 
   void collide(Vehicle v){super.collide(v);}
}  

class Truck extends Vehicle
{
   @Override 
   void collide(Vehicle v){super.collide(v);}
}  

If I do :

@Inject   
Vehicle vehicle;

1. How does @Inject know which one to instantiate ?
2. I think this will throw an AmbiguousResolutionException, am I wrong?

I would like to do this to avoid this problem and also specialize the parameters but it's not allowed, and I understand why.

class Car extends Vehicle
{
   @Override 
   void collide(Car v){super.collide(v);}
}  

class Truck extends Vehicle
{
   @Override 
   void collide(Truck v){super.collide(v);}
}  

3. What is the workaround?

Answer 1

Second answer to your edited post (as you go into a totally different problem domain here):

For the specialization of parameters, you only have the possibility to parameterize the class itself, along the lines of:

abstract class Vehicle<T> {  // T is the "collision partner class"
    abstract void collide(T v);
}

class Car extends Vehicle<Car> {
    @Override 
    void collide(Car v) { ... }
}

You can then inject a specialized type:

@Inject Vehicle<Car> thisIsACar;

Nevertheless, judging from your example, this is probably not what you want ;-)