net.esper.eql.agg
Interface AggregationService

All Superinterfaces:

AggregationResultFuture

All Known Implementing Classes:

AggregationServiceBase, AggregationServiceGroupAllImpl, AggregationServiceGroupByImpl, AggregationServiceNull

public interface AggregationService
extends AggregationResultFuture

Service for maintaing aggregation state. Processes events entering (a window, a join etc,) and events leaving. Answers questions about current aggrataion state for a given row.

Method Summary

void	applyEnter(EventBean[] eventsPerStream, MultiKeyUntyped optionalGroupKeyPerRow) Apply events as entering a window (new events).
void	applyLeave(EventBean[] eventsPerStream, MultiKeyUntyped optionalGroupKeyPerRow) Apply events as leaving a window (old events).
void	setCurrentRow(MultiKeyUntyped groupKey) Set the current aggregation state row - for use when evaluation nodes are asked to evaluate.

Methods inherited from interface net.esper.eql.agg.AggregationResultFuture

getValue

Method Detail

applyEnter

void applyEnter(EventBean[] eventsPerStream,
                MultiKeyUntyped optionalGroupKeyPerRow)

Apply events as entering a window (new events).

Parameters:

eventsPerStream - - events for each stream entering window

optionalGroupKeyPerRow - - can be null if grouping without keys is desired, else the keys to use for grouping, each distinct key value results in a new row of aggregation state.

applyLeave

void applyLeave(EventBean[] eventsPerStream,
                MultiKeyUntyped optionalGroupKeyPerRow)

Apply events as leaving a window (old events).

Parameters:

eventsPerStream - - events for each stream entering window

optionalGroupKeyPerRow - - can be null if grouping without keys is desired, else the keys to use for grouping, each distinct key value results in a new row of aggregation state.

setCurrentRow

void setCurrentRow(MultiKeyUntyped groupKey)

Set the current aggregation state row - for use when evaluation nodes are asked to evaluate.

Parameters:

groupKey - - key identify the row of aggregation states