Package org.apache.druid.query.topn

Class BaseTopNAlgorithm<DimValSelector,DimValAggregateStore,Parameters extends TopNParams>

java.lang.Object

org.apache.druid.query.topn.BaseTopNAlgorithm<DimValSelector,DimValAggregateStore,Parameters>

All Implemented Interfaces:

TopNAlgorithm<DimValSelector,Parameters>

Direct Known Subclasses:

HeapBasedTopNAlgorithm, PooledTopNAlgorithm, TimeExtractionTopNAlgorithm

public abstract class BaseTopNAlgorithm<DimValSelector,DimValAggregateStore,Parameters extends TopNParams>
extends Object
implements TopNAlgorithm<DimValSelector,Parameters>

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BaseTopNAlgorithm.AggregatorArrayProvider
protected static class	BaseTopNAlgorithm.BaseArrayProvider<T>

Field Summary

Fields

Modifier and Type	Field	Description
protected TopNCursorInspector	cursorInspector

Fields inherited from interface org.apache.druid.query.topn.TopNAlgorithm

EMPTY_ARRAY, INIT_POSITION_VALUE, SKIP_POSITION_VALUE

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	BaseTopNAlgorithm(TopNCursorInspector cursorInspector)

Method Summary

Modifier and Type	Method	Description
protected int	computeNewLength(DimValSelector dimValSelector, int numProcessed, int numToProcess)	Skip invalid value, calculate length to have enough valid value to process or hit the end.
static Aggregator[]	makeAggregators(Cursor cursor, List<AggregatorFactory> aggregatorSpecs)
protected static BufferAggregator[]	makeBufferAggregators(Cursor cursor, List<AggregatorFactory> aggregatorSpecs)
protected abstract DimValAggregateStore	makeDimValAggregateStore(Parameters params)
protected abstract DimValSelector	makeDimValSelector(Parameters params, int numProcessed, int numToProcess)
static TopNResultBuilder	makeResultBuilder(TopNParams params, TopNQuery query)
protected abstract void	resetAggregators(DimValAggregateStore dimValAggregateStore)
void	run(Parameters params, TopNResultBuilder resultBuilder, DimValSelector dimValSelector, TopNQueryMetrics queryMetrics)
protected abstract long	scanAndAggregate(Parameters params, DimValSelector dimValSelector, DimValAggregateStore dimValAggregateStore)	Returns the number of processed rows (i.
protected abstract DimValSelector	updateDimValSelector(DimValSelector dimValSelector, int numProcessed, int numToProcess)
protected abstract void	updateResults(Parameters params, DimValSelector dimValSelector, DimValAggregateStore dimValAggregateStore, TopNResultBuilder resultBuilder)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.druid.query.topn.TopNAlgorithm

cleanup, makeInitParams

Field Details

cursorInspector

protected TopNCursorInspector cursorInspector

Constructor Details

BaseTopNAlgorithm

protected BaseTopNAlgorithm(TopNCursorInspector cursorInspector)

Method Details

makeAggregators

public static Aggregator[] makeAggregators(Cursor cursor,
 List<AggregatorFactory> aggregatorSpecs)

makeBufferAggregators

protected static BufferAggregator[] makeBufferAggregators(Cursor cursor,
 List<AggregatorFactory> aggregatorSpecs)

run

public void run(Parameters params,
 TopNResultBuilder resultBuilder,
 DimValSelector dimValSelector,
 @Nullable
 TopNQueryMetrics queryMetrics)

Specified by:

run in interface TopNAlgorithm<DimValSelector,DimValAggregateStore>

makeDimValSelector

protected abstract DimValSelector makeDimValSelector(Parameters params,
 int numProcessed,
 int numToProcess)

computeNewLength

protected int computeNewLength(DimValSelector dimValSelector,
 int numProcessed,
 int numToProcess)

Skip invalid value, calculate length to have enough valid value to process or hit the end.

Parameters:

dimValSelector - the dim value selector which record value is valid or invalid.

numProcessed - the start position to process

numToProcess - the number of valid value to process

Returns:

the length between which have enough valid value to process or hit the end.

updateDimValSelector

protected abstract DimValSelector updateDimValSelector(DimValSelector dimValSelector,
 int numProcessed,
 int numToProcess)

makeDimValAggregateStore

protected abstract DimValAggregateStore makeDimValAggregateStore(Parameters params)

scanAndAggregate

protected abstract long scanAndAggregate(Parameters params,
 DimValSelector dimValSelector,
 DimValAggregateStore dimValAggregateStore)

Returns the number of processed rows (i. e. after postFilters are applied inside the cursor being processed).

updateResults

protected abstract void updateResults(Parameters params,
 DimValSelector dimValSelector,
 DimValAggregateStore dimValAggregateStore,
 TopNResultBuilder resultBuilder)

resetAggregators

protected abstract void resetAggregators(DimValAggregateStore dimValAggregateStore)

makeResultBuilder

public static TopNResultBuilder makeResultBuilder(TopNParams params,
 TopNQuery query)