com.espertech.esper.common.internal.epl.agg.core

Interface AggregationService

All Superinterfaces:

AggregationResultFuture, StopCallback

All Known Subinterfaces:

AIRegistryAggregation

All Known Implementing Classes:

AggregationServiceNull, AggSvcGroupAllWTableImpl, AggSvcGroupByWTableBase, AggSvcGroupByWTableImpl, AggSvcGroupByWTableRollupMultiKeyImpl, AggSvcGroupByWTableRollupSingleKeyImpl, AIRegistryAggregationMap, AIRegistryAggregationMultiPerm, AIRegistryAggregationSingle

public interface AggregationService
extends AggregationResultFuture, StopCallback

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

Method Summary

Modifier and Type	Method and Description
void	accept(AggregationServiceVisitor visitor)
void	acceptGroupDetail(AggregationServiceVisitorWGroupDetail visitor)
void	applyEnter(EventBean[] eventsPerStream, Object optionalGroupKeyPerRow, ExprEvaluatorContext exprEvaluatorContext) Apply events as entering a window (new events).
void	applyLeave(EventBean[] eventsPerStream, Object optionalGroupKeyPerRow, ExprEvaluatorContext exprEvaluatorContext) Apply events as leaving a window (old events).
void	clearResults(ExprEvaluatorContext exprEvaluatorContext) Clear current aggregation state.
boolean	isGrouped()
void	setRemovedCallback(AggregationRowRemovedCallback callback)

Methods inherited from interface com.espertech.esper.common.internal.epl.agg.core.AggregationResultFuture

getCollectionOfEvents, getCollectionScalar, getContextPartitionAggregationService, getEventBean, getGroupKey, getGroupKeys, getValue, setCurrentAccess

Methods inherited from interface com.espertech.esper.common.internal.util.StopCallback

stop

Method Detail

applyEnter

void applyEnter(EventBean[] eventsPerStream,
                Object optionalGroupKeyPerRow,
                ExprEvaluatorContext exprEvaluatorContext)

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 or array of keys to use for grouping, each distinct key value results in a new row of aggregation state.

exprEvaluatorContext - context for expression evaluatiom

applyLeave

void applyLeave(EventBean[] eventsPerStream,
                Object optionalGroupKeyPerRow,
                ExprEvaluatorContext exprEvaluatorContext)

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 or array of keys to use for grouping, each distinct key value results in a new row of aggregation state.

exprEvaluatorContext - context for expression evaluatiom

clearResults

void clearResults(ExprEvaluatorContext exprEvaluatorContext)

Clear current aggregation state.

Parameters:

exprEvaluatorContext - context

setRemovedCallback

void setRemovedCallback(AggregationRowRemovedCallback callback)

accept

void accept(AggregationServiceVisitor visitor)

acceptGroupDetail

void acceptGroupDetail(AggregationServiceVisitorWGroupDetail visitor)

isGrouped

boolean isGrouped()