The following code should be rejected by javac:

class Param<T> {}
interface A { void f(Param<String> ls); }
interface B extends A { void f(Param<Integer> li); }

JLS 9.4.1 Inheritance and Overriding:
--
It is a compile time error if a type declaration T has a member method m1 and there exists a method m2 declared in T or a supertype of T such that all of the following conditions hold:

* m1 and m2 have the same name.
* m2 is accessible from T.
* The signature of m1 is not a subsignature (§8.4.2) of the signature of m2.
* m1 or some method m1 overrides (directly or indirectly) has the same erasure as m2 or some method m2 overrides (directly or indirectly).
--

Thus, interface B should generate a compile-time error:

- B.f and A.f have the same name
- A.f is accessible from B
- The signature of B.f is not a subsignature of A.f
- B.f has the same erasure as A.f