public void method(Map<?, Model> map){

    Map<UUID, Model> transformation = map.entrySet()
.stream()
.collect(Collectors.toMap(
   entry -> entry.getKey().getId(),
    entry-> entry.getValue()
    ));
}


    class S{
     protected UUID getId(){
     // return UUID
     }
    }

    class A extends S{
    }
    class B extends S{
    }
    class Model{
    // bla bla
    }