org.apache.druid.query.aggregation

Class DoubleMinAggregatorFactory

java.lang.Object

org.apache.druid.query.aggregation.AggregatorFactory

org.apache.druid.query.aggregation.NullableAggregatorFactory<BaseDoubleColumnValueSelector>

org.apache.druid.query.aggregation.SimpleDoubleAggregatorFactory

org.apache.druid.query.aggregation.DoubleMinAggregatorFactory

All Implemented Interfaces:

Cacheable

public class DoubleMinAggregatorFactory
extends SimpleDoubleAggregatorFactory

Field Summary

Fields inherited from class org.apache.druid.query.aggregation.SimpleDoubleAggregatorFactory

expression, fieldName, macroTable, name, storeDoubleAsFloat

Constructor Summary

Constructors

Constructor and Description
DoubleMinAggregatorFactory(String name, String fieldName)
DoubleMinAggregatorFactory(String name, String fieldName, String expression, ExprMacroTable macroTable)

Method Summary

Modifier and Type	Method and Description
Object	combine(Object lhs, Object rhs) A method that knows how to combine the outputs of Aggregator.get() produced via AggregatorFactory.factorize(org.apache.druid.segment.ColumnSelectorFactory) or BufferAggregator.get(java.nio.ByteBuffer, int) produced via AggregatorFactory.factorizeBuffered(org.apache.druid.segment.ColumnSelectorFactory).
protected Aggregator	factorize(ColumnSelectorFactory metricFactory, BaseDoubleColumnValueSelector selector) Creates an Aggregator to aggregate values from several rows, by using the provided selector.
protected BufferAggregator	factorizeBuffered(ColumnSelectorFactory metricFactory, BaseDoubleColumnValueSelector selector) Creates an BufferAggregator to aggregate values from several rows into a ByteBuffer.
byte[]	getCacheKey()
AggregatorFactory	getCombiningFactory() Returns an AggregatorFactory that can be used to combine the output of aggregators from this factory.
List<AggregatorFactory>	getRequiredColumns() Gets a list of all columns that this AggregatorFactory will scan
AggregateCombiner	makeAggregateCombiner() Creates an AggregateCombiner to fold rollup aggregation results from serveral "rows" of different indexes during index merging.
protected BaseDoubleColumnValueSelector	selector(ColumnSelectorFactory metricFactory) Creates a ColumnValueSelector for the aggregated column.
String	toString()

Methods inherited from class org.apache.druid.query.aggregation.SimpleDoubleAggregatorFactory

deserialize, equals, finalizeComputation, getComparator, getDoubleColumnSelector, getExpression, getFieldName, getMaxIntermediateSize, getMergingFactory, getName, getTypeName, hashCode, requiredFields

Methods inherited from class org.apache.druid.query.aggregation.NullableAggregatorFactory

factorize, factorizeBuffered, getMaxIntermediateSizeWithNulls, makeNullableAggregateCombiner

Methods inherited from class org.apache.druid.query.aggregation.AggregatorFactory

mergeAggregators, optimizeForSegment

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

DoubleMinAggregatorFactory

public DoubleMinAggregatorFactory(String name,
                                  String fieldName,
                                  String expression,
                                  ExprMacroTable macroTable)

DoubleMinAggregatorFactory

public DoubleMinAggregatorFactory(String name,
                                  String fieldName)

Method Detail

selector

protected BaseDoubleColumnValueSelector selector(ColumnSelectorFactory metricFactory)

Description copied from class: NullableAggregatorFactory

Creates a ColumnValueSelector for the aggregated column.

Specified by:

selector in class NullableAggregatorFactory<BaseDoubleColumnValueSelector>

See Also:

ColumnValueSelector

factorize

protected Aggregator factorize(ColumnSelectorFactory metricFactory,
                               BaseDoubleColumnValueSelector selector)

Description copied from class: NullableAggregatorFactory

Creates an Aggregator to aggregate values from several rows, by using the provided selector.

Specified by:

factorize in class NullableAggregatorFactory<BaseDoubleColumnValueSelector>

Parameters:

metricFactory - metricFactory

selector - ColumnValueSelector for the column to aggregate.

See Also:

Aggregator

factorizeBuffered

protected BufferAggregator factorizeBuffered(ColumnSelectorFactory metricFactory,
                                             BaseDoubleColumnValueSelector selector)

Description copied from class: NullableAggregatorFactory

Creates an BufferAggregator to aggregate values from several rows into a ByteBuffer.

Specified by:

factorizeBuffered in class NullableAggregatorFactory<BaseDoubleColumnValueSelector>

Parameters:

metricFactory - metricFactory

selector - ColumnValueSelector for the column to aggregate.

See Also:

BufferAggregator

combine

@Nullable
public Object combine(@Nullable
                                Object lhs,
                                @Nullable
                                Object rhs)

Description copied from class: AggregatorFactory

A method that knows how to combine the outputs of Aggregator.get() produced via AggregatorFactory.factorize(org.apache.druid.segment.ColumnSelectorFactory) or BufferAggregator.get(java.nio.ByteBuffer, int) produced via AggregatorFactory.factorizeBuffered(org.apache.druid.segment.ColumnSelectorFactory). Note, even though this method is called "combine", this method's contract *does* allow for mutation of the input objects. Thus, any use of lhs or rhs after calling this method is highly discouraged.

Specified by:

combine in class AggregatorFactory

Parameters:

lhs - The left hand side of the combine

rhs - The right hand side of the combine

Returns:

an object representing the combination of lhs and rhs, this can be a new object or a mutation of the inputs

makeAggregateCombiner

public AggregateCombiner makeAggregateCombiner()

Description copied from class: AggregatorFactory

Creates an AggregateCombiner to fold rollup aggregation results from serveral "rows" of different indexes during index merging. AggregateCombiner implements the same logic as AggregatorFactory.combine(java.lang.Object, java.lang.Object), with the difference that it uses ColumnValueSelector and it's subinterfaces to get inputs and implements ColumnValueSelector to provide output.

Overrides:

makeAggregateCombiner in class AggregatorFactory

See Also:

AggregateCombiner, IndexMerger

getCombiningFactory

public AggregatorFactory getCombiningFactory()

Description copied from class: AggregatorFactory

Returns an AggregatorFactory that can be used to combine the output of aggregators from this factory. This generally amounts to simply creating a new factory that is the same as the current except with its input column renamed to the same as the output column.

Specified by:

getCombiningFactory in class AggregatorFactory

Returns:

a new Factory that can be used for operations on top of data output from the current factory.

getRequiredColumns

public List<AggregatorFactory> getRequiredColumns()

Description copied from class: AggregatorFactory

Gets a list of all columns that this AggregatorFactory will scan

Specified by:

getRequiredColumns in class AggregatorFactory

Returns:

AggregatorFactories for the columns to scan of the parent AggregatorFactory

getCacheKey

public byte[] getCacheKey()

toString

public String toString()

Overrides:

toString in class Object