Spring factory method

Question

I need to dynamically get a service bean in a controller from a factory method. I have a service interface

public interface Service{
     public String doSomething();
}

and some implementation of this interface.

public class ServiceImpl1{
    public String doSomething(){
      ...
    }
}

public class ServiceImpl2{
    public String doSomething(){
      ...
    }
}

There are 20 such implementations.

Now, in my controller I want to get one of these service impl instance, with dependency injected, based on user request. I am thinking of using a factory method to give me the instance, but to get dependency injected bean I need to load the context and get the bean. Is there any better way of doing it in Spring.