but i can't use the methods in the class ( which is in the jar) ..
For example, the class NumericOperation has a method which is add ;
when i tried to create object for the class to call the method, the program give me error because the constructor of the class is not visible ..
I tried several things to use the methods which are in the class ( in the jar ) ...
first, i tried to create an instance, but it doesn't work because the constructor is not visible ...
second, i tried to use the class as abstract class and extend it on the new class .. but also it give me the same error ( constructor is not visible ) ..
I don't know what can i do to use the class's methods !!