### Question:
SortedRangeSet implements ValueSet { @Override public Object getSingleValue() { if (!isSingleValue()) { throw new IllegalStateException("SortedRangeSet does not have just a single value"); } return lowIndexedRanges.values().iterator().next().getSingleValue(); } private  SortedRangeSet(Type type, NavigableMap<Marker, Range> lowIndexedRanges); @JsonCreator static SortedRangeSet copyOf(
            @JsonProperty("type") Type type,
            @JsonProperty("ranges") List<Range> ranges); @Override @JsonProperty Type getType(); @JsonProperty("ranges") List<Range> getOrderedRanges(); int getRangeCount(); @Override boolean isNone(); @Override boolean isAll(); @Override boolean isSingleValue(); @Override Object getSingleValue(); @Override boolean isDiscreteSet(); @Override List<Object> getDiscreteSet(); @Override boolean containsValue(Object value); Range getSpan(); @Override Ranges getRanges(); @Override ValuesProcessor getValuesProcessor(); @Override SortedRangeSet intersect(ValueSet other); @Override boolean overlaps(ValueSet other); @Override SortedRangeSet union(ValueSet other); @Override SortedRangeSet union(Collection<ValueSet> valueSets); @Override SortedRangeSet complement(); @Override int hashCode(); @Override boolean equals(Object obj); @Override String toString(); @Override String toString(ConnectorSession session);  }### Answer:
@Test public void testGetSingleValue() { assertEquals(SortedRangeSet.of(BIGINT, 0L).getSingleValue(), 0L); assertThatThrownBy(() -> SortedRangeSet.all(BIGINT).getSingleValue()) .isInstanceOf(IllegalStateException.class) .hasMessage("SortedRangeSet does not have just a single value"); }