@CanIgnoreReturnValue
    private int collectTypes(K type, Map<? super K, Integer> map) {
      Integer existing = map.get(type);
      if (existing != null) {
        // short circuit: if set contains type it already contains its supertypes
        return existing;
      }
      // Interfaces should be listed before Object.
      int aboveMe = getRawType(type).isInterface() ? 1 : 0;