Class TwoStepMapper.KeyCounter<T,G>

java.lang.Object

org.ojalgo.type.function.TwoStepMapper.KeyCounter<T,G>

All Implemented Interfaces:

TwoStepMapper<T, FrequencyMap<G>>, TwoStepMapper.Combineable<T, FrequencyMap<G>, TwoStepMapper.KeyCounter<T,G>>, TwoStepMapper.Mergeable<T, FrequencyMap<G>>

Enclosing interface:

TwoStepMapper<T,R>

public static final class TwoStepMapper.KeyCounter<T,G>
extends Object
implements TwoStepMapper.Combineable<T, FrequencyMap<G>, TwoStepMapper.KeyCounter<T,G>>, TwoStepMapper.Mergeable<T, FrequencyMap<G>>

A frequency counter that optionally filters some elements when merging subresults.

Nested Class Summary

Nested classes/interfaces inherited from interface TwoStepMapper

TwoStepMapper.Combineable<T,R,A>, TwoStepMapper.KeyCounter<T,G>, TwoStepMapper.Mergeable<T,R>, TwoStepMapper.SimpleCache<K,V>

Field Summary

Fields

Modifier and Type	Field	Description
private final FrequencyMap<G>	myCounter
private final Function<T,G>	myExtractor
private final FrequencyMap.FrequencyPredicate<G>	myPredicate

Constructor Summary

Constructors

Constructor	Description
KeyCounter(Function<T,G> extractor)
KeyCounter(Function<T,G> extractor, FrequencyMap.FrequencyPredicate<G> predicate)

Method Summary

Modifier and Type	Method	Description
void	combine(TwoStepMapper.KeyCounter<T,G> other)	This method can be used to combine the state of multiple instances.
void	consume(T item)	Input/consume the items that should be mapped
(package private) FrequencyMap<G>	getCounter()
FrequencyMap<G>	getResults()	Output the mapped results
void	merge(FrequencyMap<G> other)	This method can be used to merge the results from multiple instances.
static <T> TwoStepMapper.KeyCounter<T,T>	newInstance()
static <T> TwoStepMapper.KeyCounter<T,T>	newInstance(FrequencyMap.FrequencyPredicate<T> predicate)
void	reset()	Reset, so it can be re-used

Methods inherited from class Object

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

Field Details

myCounter

private final FrequencyMap<G> myCounter

myExtractor

private final Function<T,G> myExtractor

myPredicate

private final FrequencyMap.FrequencyPredicate<G> myPredicate

Constructor Details

KeyCounter

public KeyCounter(Function<T,G> extractor)

Parameters:

extractor - The key extractor

KeyCounter

public KeyCounter(Function<T,G> extractor,
 FrequencyMap.FrequencyPredicate<G> predicate)

Parameters:

extractor - The key extractor

predicate - Filter used when merging/combining results

Method Details

newInstance

public static <T> TwoStepMapper.KeyCounter<T,T> newInstance()

newInstance

public static <T> TwoStepMapper.KeyCounter<T,T> newInstance(FrequencyMap.FrequencyPredicate<T> predicate)

combine

public void combine(TwoStepMapper.KeyCounter<T,G> other)

Description copied from interface: TwoStepMapper.Combineable

This method can be used to combine the state of multiple instances. The intermediate/internal state from one instance is combined into another.

Specified by:

combine in interface TwoStepMapper.Combineable<T, FrequencyMap<G>, TwoStepMapper.KeyCounter<T,G>>

consume

public void consume(T item)

Description copied from interface: TwoStepMapper

Input/consume the items that should be mapped

Specified by:

consume in interface TwoStepMapper<T,G>

getResults

public FrequencyMap<G> getResults()

Description copied from interface: TwoStepMapper

Output the mapped results

Specified by:

getResults in interface TwoStepMapper<T,G>

merge

public void merge(FrequencyMap<G> other)

Description copied from interface: TwoStepMapper.Mergeable

This method can be used to merge the results from multiple instances. The final results from one instance is merged into another.

Specified by:

merge in interface TwoStepMapper.Mergeable<T,G>

reset

public void reset()

Description copied from interface: TwoStepMapper

Reset, so it can be re-used

Specified by:

reset in interface TwoStepMapper<T,G>

getCounter

FrequencyMap<G> getCounter()