Android Question ARR files

Hi
somebody can help me?
I need to use an external arr file.
I've extracted the .jar file
I used #AdditionalJar:
Inside i have the class:

net.cobogroup.lib
Class Lib

java.lang.Object
net.cobogroup.lib.Lib

public class Lib
extends java.lang.Object
Copyright 2016 Cobo Group S.R.L. All rights reserved.
Created by Giuseppe Liguori on 10/02/16.
Constructor Summary

Constructors
Constructor and Description
Lib(Context context)
For all status updates, the inteface OnUpdate will call "onStateChange".

I call the class with
mylib.InitializeStatic( "net.cobogroup.lib.Lib")
and i have no problem.

when i call the metod scan (with no parameters) using mylib.RunMethodJO("scan",Null)
i receive the error
java.lang.IllegalArgumentException: Expected receiver of type net.cobogroup.lib.Lib, but got java.lang.Class<net.cobogroup.lib.Lib>

Attached the documentation of the library and the .jar file

somebody can help me to find a solution?

Thanks!