Fun with generics

gistfile1.txt

package it.lm;

public class Main {

    public static void main(String[] args) {
        B b = new B();
        A<B> a = new A<B>(b);

        C<A<B>> c = new C<A<B>>(a);
    }
}

class B {

}

class A<S extends B> {
    B s;

    A(B s) {
        this.s = s;
    }
}

class C<S2 extends A<B>> {
    A<B> a;

    C(A<B> a) {
        this.a = a;
    }
}