code: @Override
      public boolean addAll(Collection<? extends BannerAdPreset> c) {
          ArrayList<BannerAdPreset> lst = new ArrayList<>();
          for (BannerAdPreset eap : c) {
              if(eap!=null && eap.isValid())
                  lst.add(eap);
          }
          return super.addAll(lst);
      }
docs: Tries to add items to collection if valid {@link BannerAdPreset#isValid()}
  @return true if items were added, false - otherwise