### Question:
StroomDuration implements Comparable<StroomDuration>, TemporalAmount { @JsonIgnore public Duration getDuration() { return duration; } private  StroomDuration(@Nullable final String valueAsStr,
                           final Duration duration); private  StroomDuration(final TemporalAmount temporalAmount); @JsonCreator static StroomDuration parse(final String value); static StroomDuration of(final TemporalAmount temporalAmount); static StroomDuration of(final long amount, final TemporalUnit unit); static StroomDuration ofDays(final long days); static StroomDuration ofHours(final long hours); static StroomDuration ofMinutes(final long minutes); static StroomDuration ofSeconds(final long seconds); static StroomDuration ofMillis(final long millis); static StroomDuration ofNanos(final long nanos); @SuppressWarnings("unused") @JsonValue String getValueAsStr(); @JsonIgnore Duration getDuration(); long toMillis(); long toNanos(); @JsonIgnore boolean isZero(); @Override String toString(); @Override boolean equals(final Object o); @Override int hashCode(); @Override int compareTo(final StroomDuration o); @Override long get(final TemporalUnit unit); @JsonIgnore @Override List<TemporalUnit> getUnits(); @Override Temporal addTo(final Temporal temporal); @Override Temporal subtractFrom(final Temporal temporal); static final StroomDuration ZERO; }### Answer:
@Test void getDuration() { final String input = "P30D"; final StroomDuration stroomDuration = StroomDuration.parse(input); assertThat(stroomDuration.getDuration()) .isEqualTo(Duration.ofDays(30)); }