com.espertech.esper.epl.agg.aggregator

Class AggregatorDistinctValue

java.lang.Object

com.espertech.esper.epl.agg.aggregator.AggregatorDistinctValue

All Implemented Interfaces:

AggregationMethod

public class AggregatorDistinctValue
extends Object
implements AggregationMethod

AggregationMethod for use on top of another aggregator that handles unique value aggregation (versus all-value aggregation) for the underlying aggregator.

Field Summary

Fields

Modifier and Type	Field and Description
protected AggregationMethod	inner
protected RefCountedSet<Object>	valueSet

Constructor Summary

Constructors

Constructor and Description
AggregatorDistinctValue(AggregationMethod inner) Ctor.

Method Summary

Modifier and Type	Method and Description
void	clear() Clear out the collection.
void	enter(Object value) Apply the value as entering aggregation (entering window).
Object	getValue() Returns the current value held.
void	leave(Object value) Apply the value as leaving aggregation (leaving window).

Methods inherited from class java.lang.Object

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

Field Detail

inner

protected final AggregationMethod inner

valueSet

protected final RefCountedSet<Object> valueSet

Constructor Detail

AggregatorDistinctValue

public AggregatorDistinctValue(AggregationMethod inner)

Ctor.

Parameters:

inner - is the aggregator function computing aggregation values

Method Detail

clear

public void clear()

Description copied from interface: AggregationMethod

Clear out the collection.

Specified by:

clear in interface AggregationMethod

enter

public void enter(Object value)

Description copied from interface: AggregationMethod

Apply the value as entering aggregation (entering window).

The value can be null since 'null' values may be counted as unique separate values.

Specified by:

enter in interface AggregationMethod

Parameters:

value - to add to aggregate

leave

public void leave(Object value)

Description copied from interface: AggregationMethod

Apply the value as leaving aggregation (leaving window).

The value can be null since 'null' values may be counted as unique separate values.

Specified by:

leave in interface AggregationMethod

Parameters:

value - to remove from aggregate

getValue

public Object getValue()

Description copied from interface: AggregationMethod

Returns the current value held.

Specified by:

getValue in interface AggregationMethod

Returns:

current value