### Question:
IborAveragedFixing implements ImmutableBean, Serializable { public static IborAveragedFixing of(IborIndexObservation observation) { return of(observation, null); } private  IborAveragedFixing(
      IborIndexObservation observation,
      Double fixedRate,
      double weight); static IborAveragedFixing of(IborIndexObservation observation); static IborAveragedFixing of(IborIndexObservation observation, Double fixedRate); static IborAveragedFixing ofDaysInResetPeriod(
      IborIndexObservation observation,
      LocalDate startDate,
      LocalDate endDate); static IborAveragedFixing ofDaysInResetPeriod(
      IborIndexObservation observation,
      LocalDate startDate,
      LocalDate endDate,
      Double fixedRate); static IborAveragedFixing.Meta meta(); static IborAveragedFixing.Builder builder(); @Override IborAveragedFixing.Meta metaBean(); IborIndexObservation getObservation(); OptionalDouble getFixedRate(); double getWeight(); Builder toBuilder(); @Override boolean equals(Object obj); @Override int hashCode(); @Override String toString();  }### Answer:
@Test public void test_of_date_null() { assertThatIllegalArgumentException() .isThrownBy(() -> IborAveragedFixing.of(null)); assertThatIllegalArgumentException() .isThrownBy(() -> IborAveragedFixing.of(null, 0.05)); assertThatIllegalArgumentException() .isThrownBy(() -> IborAveragedFixing.of(null, null)); }
@Test public void coverage() { IborAveragedFixing test = IborAveragedFixing.of(GBP_LIBOR_3M_OBS); coverImmutableBean(test); }
@Test public void test_serialization() { IborAveragedFixing test = IborAveragedFixing.of(GBP_LIBOR_3M_OBS); assertSerialization(test); }