Re: problems with subclass

["Marcelo D. RÃ" <mdre at rectorado dot unl dot edu dot ar>]

Per Bothner escribiÃ:
> Marcelo D. RÃ wrote:
> >    I'm trying to subclass a Java class but it doesn't  work 
> > correctly.  ....
> > Exception in thread "main" java.lang.NoSuchFieldError: Lit0
> >        at colony.FunctionalAntQueen.<init>(FunctionalAntQueen.scm:8)
>
> The problem is probably because the FunctionalAntQueen class is not
> self-contained, but depends on the enclosing "module class", which
> contains top-level definitions (none in this case, except the
> FunctionalAntQueen) and compiler-generated members such as literals.
>
> You probably want to compile using the flag --module-static-run
> command-line option, or (equivalently) put (module-static 'init-run)
> in your file.  See
> http://www.gnu.org/software/kawa/Compilation-options.html
> http://www.gnu.org/software/kawa/Module-classes.html#id2600899
>
> It looks like things are further messed up because the name of the
> module class is the same as the define-simple-class.  Kawa doesn't
> handle this well.  (I vaguely remember putting in a test for this
> in SVN Kawa, but I'm not sure.)
>
> You could try putting something like
>   (module-name FunctionalAntQueenModule)
> in your .scm file.
Thanks for yours answer!

    But I need the class not be static. I'am working in a virtual live 
game to teach diferent programming paradigm. OO, functional (with 
scheme), and Logic (with prolog). To make the course more interesting i 
design a game called AntWar. The engine instantiate your class whose 
simulate an ant and call you to move in the warfield. Your AntQueen can 
create more ants (AntWarriors/AntWorkers) and must survive against other 
colonys in the game.
   So, I need to extends the base class but every instance must have 
their own state.

   Just now, it return to work! I put an asignation in the contructor 
to test, but I don't know why. It work yesterday, today morning not 
work, and now work again. The new problem is, that the method "move" 
does not overwrite de inherited move.

   This is the scm code:

(define-simple-class <FunctionalAntQueen> (<engine.AntQueen>)
 ((*init*)
  (set! name "FunctionalAntQueen")
 )
 ((move)
  (set! name "MOVE")
  )
 )

   but if you try this:

try {
           // TODO code application logic here
           //ContestEngine ce = new ContestEngine();
           Object preAnt = 
Class.forName("colony.FunctionalAntQueen").newInstance();
       
           //TestAQ aq = new TestAQ();
           if (preAnt instanceof AntQueen) {
               System.out.println("SIIII!");
               ((AntQueen)preAnt).move();
               System.out.println(((AntQueen)preAnt).name);
              
           }


it yield

   FunctionalAntQueen

to the console

   Any idea?



   Thank for your time. The game will be available soon in sourceforge.

   Marcelo