How to use

CardinalityAggregatorFactory

in

org.apache.druid.query.aggregation.cardinality

@Override
public List<AggregatorFactory> getRequiredColumns()
{
 return fields.stream()
        .map(
          field ->
            new CardinalityAggregatorFactory(
              field.getOutputName(),
              null,
              Collections.singletonList(field),
              byRow,
              round
            )
        )
        .collect(Collectors.toList());
}

@Test
public void testBufferAggregateRows()
{
 CardinalityBufferAggregator agg = new CardinalityBufferAggregator(
   dimInfoList.toArray(new ColumnSelectorPlus[0]),
   true
 );
 int maxSize = rowAggregatorFactory.getMaxIntermediateSizeWithNulls();
 ByteBuffer buf = ByteBuffer.allocate(maxSize + 64);
 int pos = 10;
 buf.limit(pos + maxSize);
 agg.init(buf, pos);
 for (int i = 0; i < values1.size(); ++i) {
  bufferAggregate(selectorList, agg, buf, pos);
 }
 Assert.assertEquals(9.0, (Double) rowAggregatorFactory.finalizeComputation(agg.get(buf, pos)), 0.05);
 Assert.assertEquals(9L, rowAggregatorFactoryRounded.finalizeComputation(agg.get(buf, pos)));
}

@JsonCreator
public CardinalityAggregatorFactory(
  @JsonProperty("name") String name,
  @Deprecated @JsonProperty("fieldNames") final List<String> fieldNames,
  @JsonProperty("fields") final List<DimensionSpec> fields,
  @JsonProperty("byRow") final boolean byRow,
  @JsonProperty("round") final boolean round
)
{
 this.name = name;
 // 'fieldNames' is deprecated, since CardinalityAggregatorFactory now accepts DimensionSpecs instead of Strings.
 // The old 'fieldNames' is still supported for backwards compatibility, but the user is not allowed to specify both
 // 'fields' and 'fieldNames'.
 if (fields == null) {
  Preconditions.checkArgument(fieldNames != null, "Must provide 'fieldNames' if 'fields' is null.");
  this.fields = makeFieldsFromFieldNames(fieldNames);
 } else {
  Preconditions.checkArgument(fieldNames == null, "Cannot specify both 'fieldNames' and 'fields.");
  this.fields = fields;
 }
 this.byRow = byRow;
 this.round = round;
}

CardinalityAggregatorFactory factory = new CardinalityAggregatorFactory(
  "billy",
  Collections.singletonList(new DefaultDimensionSpec("dim1", "dim1")),
);
int maxSize = factory.getMaxIntermediateSizeWithNulls();
buf = ByteBuffer.allocate(maxSize + 64);
pos = 10;

Assert.assertEquals(4.0, (Double) rowAggregatorFactory.finalizeComputation(agg1.get()), 0.05);
Assert.assertEquals(8.0, (Double) rowAggregatorFactory.finalizeComputation(agg2.get()), 0.05);
  (Double) rowAggregatorFactory.finalizeComputation(
    rowAggregatorFactory.combine(
      agg1.get(),
      agg2.get()

@Test
public void testAggregateRows()
{
 CardinalityAggregator agg = new CardinalityAggregator(
   dimInfoList,
   true
 );
 for (int i = 0; i < values1.size(); ++i) {
  aggregate(selectorList, agg);
 }
 Assert.assertEquals(9.0, (Double) rowAggregatorFactory.finalizeComputation(agg.get()), 0.05);
 Assert.assertEquals(9L, rowAggregatorFactoryRounded.finalizeComputation(agg.get()));
}

@Override
public List<String> requiredFields()
{
 return makeRequiredFieldNamesFromFields(fields);
}

Assert.assertEquals(NullHandling.replaceWithDefault() ? 4.0 : 3.0, (Double) valueAggregatorFactory.finalizeComputation(agg1.get()), 0.05);
Assert.assertEquals(NullHandling.replaceWithDefault() ? 7.0 : 6.0, (Double) valueAggregatorFactory.finalizeComputation(agg2.get()), 0.05);
  (Double) rowAggregatorFactory.finalizeComputation(
    rowAggregatorFactory.combine(
      agg1.get(),
      agg2.get()

@Test
public void testAggregateValues()
{
 CardinalityAggregator agg = new CardinalityAggregator(
   dimInfoList,
   false
 );
 for (int i = 0; i < values1.size(); ++i) {
  aggregate(selectorList, agg);
 }
 Assert.assertEquals(NullHandling.replaceWithDefault() ? 7.0 : 6.0, (Double) valueAggregatorFactory.finalizeComputation(agg.get()), 0.05);
 Assert.assertEquals(NullHandling.replaceWithDefault() ? 7L : 6L, rowAggregatorFactoryRounded.finalizeComputation(agg.get()));
}

@Override
public List<String> requiredFields()
{
 return makeRequiredFieldNamesFromFields(fields);
}

ImmutableMap.of(
  "uniques",
  new CardinalityAggregatorFactory(
    "uniques",
    null,

@Test
public void testBufferAggregateValues()
{
 CardinalityBufferAggregator agg = new CardinalityBufferAggregator(
   dimInfoList.toArray(new ColumnSelectorPlus[0]),
   false
 );
 int maxSize = valueAggregatorFactory.getMaxIntermediateSizeWithNulls();
 ByteBuffer buf = ByteBuffer.allocate(maxSize + 64);
 int pos = 10;
 buf.limit(pos + maxSize);
 agg.init(buf, pos);
 for (int i = 0; i < values1.size(); ++i) {
  bufferAggregate(selectorList, agg, buf, pos);
 }
 Assert.assertEquals(NullHandling.replaceWithDefault() ? 7.0 : 6.0, (Double) valueAggregatorFactory.finalizeComputation(agg.get(buf, pos)), 0.05);
 Assert.assertEquals(NullHandling.replaceWithDefault() ? 7L : 6L, rowAggregatorFactoryRounded.finalizeComputation(agg.get(buf, pos)));
}

@Test
public void testAggregateValuesWithExtraction()
{
 CardinalityAggregator agg = new CardinalityAggregator(
   dimInfoListWithExtraction,
   false
 );
 for (int i = 0; i < values1.size(); ++i) {
  aggregate(selectorListWithExtraction, agg);
 }
 Assert.assertEquals(7.0, (Double) valueAggregatorFactory.finalizeComputation(agg.get()), 0.05);
 CardinalityAggregator agg2 = new CardinalityAggregator(
   dimInfoListConstantVal,
   false
 );
 for (int i = 0; i < values1.size(); ++i) {
  aggregate(selectorListConstantVal, agg2);
 }
 Assert.assertEquals(1.0, (Double) valueAggregatorFactory.finalizeComputation(agg2.get()), 0.05);
}

@JsonCreator
public CardinalityAggregatorFactory(
  @JsonProperty("name") String name,
  @Deprecated @JsonProperty("fieldNames") final List<String> fieldNames,
  @JsonProperty("fields") final List<DimensionSpec> fields,
  @JsonProperty("byRow") final boolean byRow,
  @JsonProperty("round") final boolean round
)
{
 this.name = name;
 // 'fieldNames' is deprecated, since CardinalityAggregatorFactory now accepts DimensionSpecs instead of Strings.
 // The old 'fieldNames' is still supported for backwards compatibility, but the user is not allowed to specify both
 // 'fields' and 'fieldNames'.
 if (fields == null) {
  Preconditions.checkArgument(fieldNames != null, "Must provide 'fieldNames' if 'fields' is null.");
  this.fields = makeFieldsFromFieldNames(fieldNames);
 } else {
  Preconditions.checkArgument(fieldNames == null, "Cannot specify both 'fieldNames' and 'fields.");
  this.fields = fields;
 }
 this.byRow = byRow;
 this.round = round;
}

aggregatorFactory = new CardinalityAggregatorFactory(
  aggregatorName,
  null,

@Test
public void testAggregateRowsWithExtraction()
{
 CardinalityAggregator agg = new CardinalityAggregator(
   dimInfoListWithExtraction,
   true
 );
 for (int i = 0; i < values1.size(); ++i) {
  aggregate(selectorListWithExtraction, agg);
 }
 Assert.assertEquals(9.0, (Double) rowAggregatorFactory.finalizeComputation(agg.get()), 0.05);
 CardinalityAggregator agg2 = new CardinalityAggregator(
   dimInfoListConstantVal,
   true
 );
 for (int i = 0; i < values1.size(); ++i) {
  aggregate(selectorListConstantVal, agg2);
 }
 Assert.assertEquals(3.0, (Double) rowAggregatorFactory.finalizeComputation(agg2.get()), 0.05);
}

.intervals(QueryRunnerTestHelper.firstToThird)
.aggregators(duplicateAggregators(
  new CardinalityAggregatorFactory("numVals", aggregatorDimensionSpecs, false),
  new CardinalityAggregatorFactory("numVals1", aggregatorDimensionSpecs, false)
))
.build();

@Test
public void testSerde() throws Exception
 CardinalityAggregatorFactory factory = new CardinalityAggregatorFactory(
   "billy",
   null,
 );
 CardinalityAggregatorFactory factory2 = new CardinalityAggregatorFactory(
   "billy",
   ImmutableList.of(

AGGS(
  new FilteredAggregatorFactory(
    new CardinalityAggregatorFactory(
      "a0",
      null,
  ),
  new FilteredAggregatorFactory(
    new CardinalityAggregatorFactory(
      "a1",
      null,

AGGS(
  new LongSumAggregatorFactory("a0", "cnt"),
  new CardinalityAggregatorFactory(
    "a1",
    null,
  ),
  new FilteredAggregatorFactory(
    new CardinalityAggregatorFactory(
      "a2",
      null,
    NOT(SELECTOR("dim2", "", null))
  ),
  new CardinalityAggregatorFactory(
    "a3",
    null,
    true
  ),
  new CardinalityAggregatorFactory(
    "a4",
    null,