Map to Class that Implements Interface

Question

I currently have

class A {...}
interface B {...}

What I would like to have is some equivalent of

HashMap<String, A implements B>

i.e., that a String maps to any instance of A that implements B. But that syntax doesn't compile. Is there any way to map to a class that implements an interface? Note also that A is not generic, so I can't do something like

A<? implements B>

Answer 1

It is possible to be done in a generic context, for instance, in a generic method:

public <T extends A & B> void method() {
    Map<String, T> map = new HashMap<>();
}

Unfortunately, we can't apply these multiple restrictions to wildcards.