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import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
 
interface Callback<T> {
    void call(T t);
}
 
class ConcreteCallback implements Callback<Collection<Object>> {
    public void call(final Collection<Object> data) {
        for (Object obj: data) {
            System.out.println(obj);
        }
    }
}
 
public class Main {
    private static <T> void call(final List<T> data, final Callback<? super List<? super T>> cb) {
        ArrayList<T> dat = new ArrayList<>();
        for (T object: data) {
            dat.add(object);
        }
        cb.call(dat);
    }
 
    public static void main(final String... args) {
        call(Arrays.asList(args), new ConcreteCallback());
    }
}

Main.java:28: error: method call in class Main cannot be applied to given types;
        call(Arrays.asList(args), new ConcreteCallback());
        ^
  required: List<T>,Callback<? super List<? super T>>
  found: List<String>,ConcreteCallback
  reason: no instance(s) of type variable(s) T exist so that argument type ConcreteCallback conforms to formal parameter type Callback<? super List<? super T>>
  where T is a type-variable:
    T extends Object declared in method <T>call(List<T>,Callback<? super List<? super T>>)
1 error

Standard output is empty