### Question:
IborInterpolatedRateComputation implements RateComputation, ImmutableBean, Serializable { public static IborInterpolatedRateComputation.Meta meta() { return IborInterpolatedRateComputation.Meta.INSTANCE; } private  IborInterpolatedRateComputation(
      IborIndexObservation shortObservation,
      IborIndexObservation longObservation); static IborInterpolatedRateComputation of(
      IborIndex index1,
      IborIndex index2,
      LocalDate fixingDate,
      ReferenceData refData); static IborInterpolatedRateComputation of(
      IborIndexObservation shortObservation,
      IborIndexObservation longObservation); LocalDate getFixingDate(); @Override void collectIndices(ImmutableSet.Builder<Index> builder); static IborInterpolatedRateComputation.Meta meta(); @Override IborInterpolatedRateComputation.Meta metaBean(); IborIndexObservation getShortObservation(); IborIndexObservation getLongObservation(); @Override boolean equals(Object obj); @Override int hashCode(); @Override String toString();  }### Answer:
@Test public void test_of_differentFixingDates() { assertThatIllegalArgumentException() .isThrownBy(() -> IborInterpolatedRateComputation.meta().builder() .set(IborInterpolatedRateComputation.meta().shortObservation(), GBP_LIBOR_1M_OBS) .set(IborInterpolatedRateComputation.meta().longObservation(), GBP_LIBOR_3M_OBS2) .build()); }