How to put twenty clowns in a Volkswagen

Context: here.

public class You {

      private static Volkswagen vw;

      private static final class Popo extends Clown {

            private static int clowns = 0;

            private boolean unpacked = false;

            public Popo() { clowns++; }

            @Override

            public int hashCode() {

                  if (!unpacked && clowns < 20) {

                        unpacked = true;

                        vw.add(new Popo());

                  }

                  return super.hashCode();

            }

      }

      public static void main(String args[]) {

            vw = new Volkswagen();

            vw.add(new Popo());

            vw.done();

      }

}

Yes, I know, this can be made shorter. Don't really care. :-)