Hi Ibrahim,
yes of course, you can not call a method if this one does not exist at all in the definition of the class. But if you create the definition of your method in your class, your code will run well.
That's why in my case, I am looking for a way to create dynamiccaly/automatically a method before calling, to make sure that my program will not dump. 
I am debugging the standard in SE24, the function group SEOD sounds good and contains all functionalities to perform my need. I am following up this trail. I will inform you if I get a solution.
Rachid.