return 0;
    }
  }

  static class BadEquals {

    public BadEquals() {} // ignored by testEquals() since it has less parameters.

    public static BadEquals create(@SuppressWarnings("unused") @Nullable String s) {
      return new BadEquals();
    }

    @Override
    public boolean equals(@Nullable Object obj) {
      return obj instanceof BadEquals;
    }

    @Override