public void addSocietyComponent(SocietyComponent sc) { if (society == null) { setSocietyComponent (sc);
public void addSocietyComponent(SocietyComponent sc) throws IllegalArgumentException { if (this.societyComponent == null) { setSocietyComponent(sc);
  public void addSocietyComponent(SocietyComponent sc) {    if (society == null) {      setSocietyComponent (sc);    } else {      throw new IllegalArgumentException("Already have a society in experiment " + this);    }  }