### Question:
VirtualMetric extends AbstractMetric<V> { @Override public int getCardinality() { return cardinality; } VirtualMetric(
      String name,
      String description,
      String valueDisplayName,
      ImmutableSet<LabelDescriptor> labels,
      Supplier<ImmutableMap<ImmutableList<String>, V>> valuesSupplier,
      Class<V> valueClass); @Override ImmutableList<MetricPoint<V>> getTimestampedValues(); @Override int getCardinality();  }### Answer:
@Test public void testGetCardinality_beforeGetTimestampedValues_returnsZero() { assertThat(metric.getCardinality()).isEqualTo(0); }