Question

I have a loop, but it is too heavy so I would like to share the same in multiple threads, but I have no idea how to do it.

while(!labyrinth.exit(bob3) && !labyrinth.exit(bob2)) {

     Collection<Room> accessibleRooms = labyrinth.accessibleRooms(bob3);

     if (bob3.canMove()) {
         destination = bob3.makeChoice(accessibleRooms);
     }

     if (destination != bob3.getPosition()) {
         destination.receive(bob3);
     }

     accessibleRooms = labyrinth.accessibleRooms(bob2);   

     if (bob2.canMove()) {
         destination = bob2.makeChoice(accessibleRooms);
     }

     if (destination != bob2.getPosition()) {
         destination.receive(bob2);
     }
}

As you can see, in this loop we have two operations that are identical so is it possible to make each one use a different thread.

Answer 1

    final CyclicBarrier c = new CyclicBarrier(2);

    Runnable r1 = new Runnable()
    {

        @Override
        public void run()
        {
            while ( !labyrinthe.sortir(bob3) )
            {

                Collection<Salle> sallesAccessibles = labyrinthe.sallesAccessibles(bob3);
                if ( bob3.peutSeDeplacer() )
                    destination = bob3.faitSonChoix(sallesAccessibles); // on demande au heros de faire son choix de salle
                if ( destination != bob3.getPosition() )
                    destination.recevoir(bob3); // deplacement
            }
            try
            {
                c.await();
            }
            catch ( InterruptedException e )
            {
                ;
            }
            catch ( BrokenBarrierException e )
            {
                ;
            }
        }
    };

    Runnable r2 = new Runnable()
    {
        @Override
        public void run()
        {
            while ( !labyrinthe.sortir(bob2) )
            {
                Collection<Salle> sallesAccessibles = labyrinthe.sallesAccessibles(bob2);
                if ( bob2.peutSeDeplacer() )
                    destination = bob2.faitSonChoix(sallesAccessibles); // on demande au heros de faire son choix de salle
                if ( destination != bob2.getPosition() )
                    destination.recevoir(bob2); // deplacement

            }
            try
            {
                c.await();
            }
            catch ( InterruptedException e )
            {
                ;
            }
            catch ( BrokenBarrierException e )
            {
                ;
            }
        }
    };

    Thread t1 = new Thread(r1);
    Thread t2 = new Thread(r2);

    t1.start();
    t2.start();

    c.await();

    System.out.println("Done");