Method taking an Object and any of its superclasses

Question

To achieve.

A method signal should take

1. any Object N
2. any of the Object's superclasses Class<?super N>

<N>void
signal(N n, Class<?super N> n_super)
{
  /*...*/
}

It should be ok to call

Object object=new Object();
signal(object, object.getClass());

since Object is a super type of object. But calling it gives a waring. In IDE words:

IntelliJ (Android Studio)

Wrong 2nd argument type. Found Class<? extends Object>, required: Class<? super Object>

Eclipse

The method signal(N, Class<? super N>) is not applicable for the arguments (Object, Class<? extends Object>)

Questions.

1. Can the goal be achieved, the way I have tried, and if yes,
2. how can the warning be eliminated

Answer 1

Turning my comments into an answer.

Two approaches I can quickly think of:

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Use Object.class directly here. signal(object, Object.class); compiles fine with no warnings on my java version.

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Change your method signature to something like:

<N, M extends N> void signal(N n, Class<? super M> n_super)

which should let you call it the way you already are (as in signal(object, object.getClass());).