Call an abstract method

Hello developers,
I am trying to implement the following (simple) classes:
class abstract_class definition abstract
     public
     create public .
     protected section
          methods parse_string abtract
               importing
                    value(i_str) type string.
          methods to_table.
endclass.
class abstract_class implementation.
     method to_table.
          me->parse_string( str ).
     endmethod.
endclass.
class other_class definition
     public
          inheriting from abstract_class
          final
          create public .
     protected section.
          methods parse_string redefinition.
endclass.
class other_class implementation.
     method parse_string.
*        some codes         
     endmethod.
endclass.
I have instantiated the class other_class. But when I call the method to_table, I am getting the error "CALL METHOD NOT IMPLEMENTED" on the method parse_string. Where is my mistake ?
Thank you for your replies.
Best regards,
Nicolas

Hello everyone,
First of all, thank you for all your reply.
During the night, I have thought to my problem and I found the solution. In fact, I made a (very) great mistake. Here is my code:
CLASS abstract_class IMPLEMENTATION.
     method constructor.
          me->to_table( ).
     endmethod.
     method to_table.
          me->parse_string( a_string ).
     endmethod.
ENDCLASS.
CLASS other_class IMPLEMENTATION.
     method constructor.
          call method super->constructor.
     endmethod.
     method parse_string.
*          some code
     endmethod.
ENDCLASS.
The problem is: I call the method parse_string of my child class (with the instruction me->parse_string) before my child class is instantiated... (Now, I can jump out the window.) Vadim Vologzhanin 's reply helped me by asking where I instantiated my child class.
Thank you !
Best regards,
Nicolas

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          setPath(path);
       //force inherting class to implement a static method
       public static abstract void setPath(String absolutePath);
    }thus simplifying ClassA and it's look-a-likes:
    public ClassA {
       private static String path;
       @Override
       public static void setPath(String absolutePath) {
          this.path = path;
      //code to provide access to native lib
    }Since static abstract methods (and overriding static methods) is not allowed, this doesn't work.
    I hope someone can catch my idea ;). Any suggestions how to do this in a nice clean way?
    Thanks in advance,
    Martin
    Edited by: morty2 on Jul 22, 2009 2:57 AM

    First of all, thanks a lot for your answer.
    YoungWinston wrote:
    Actually, you can "override" static methods (in that you can write the same method for both a subclass and a superclass, providing the superclass method isn't final); it's just that it doesn't work polymorphically. The "overriding" method masks the overridden one and the determination of what gets called is entirely down to the declared type.Yes, I know that. There's one problem: Your suggestion means that I simply have to drop the abstract modifier in the super classes setPath method. However, since the super class calls the setPath method (and not the inherting classes!) it will always be the super classes' method being called.
    YoungWinston wrote:
    Why are you so concerned with making everything static? Seems to me that the simplest solution would be to make all the contents instance-based.I want ClassA and it's look-a-likes to be set up properly at application start up, be accessible quite anytime and easily, they don't do anything themselves except for setting the path and calling into the native library which does the math. (Compareable to how you call e.g. Math.cos()). Therefore I don't think that an instance-based solution would be a better approach.
    YoungWinston wrote:
    Furthermore, you could make the class immutable; which might be a good thing - I'm not sure I'd want someone being able to change the pathname after I've >set up a class like this.Thanks for that!
    PS: As mentioned in my first post, I do have a working solution. However, I'm really corious about finding a nicer and cleaner way to do it!
    Martin

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