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

Class AggregationServiceNull

java.lang.Object

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

All Implemented Interfaces:

AggregationResultFuture, AggregationService, StopCallback

public class AggregationServiceNull
extends Object
implements AggregationService

A null object implementation of the AggregationService interface.

Field Summary

Fields

Modifier and Type	Field	Description
static final AggregationServiceNull	INSTANCE

Fields inherited from interface com.espertech.esper.common.internal.epl.agg.core.AggregationService

EPTYPE

Method Summary

Modifier and Type	Method	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.
AggregationRow	getAggregationRow(int agentInstanceId, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext)
Collection<EventBean>	getCollectionOfEvents(int column, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context)
Collection<Object>	getCollectionScalar(int column, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context)
AggregationService	getContextPartitionAggregationService(int agentInstanceId)
EventBean	getEventBean(int column, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context)
Object	getGroupKey(int agentInstanceId)
Collection<Object>	getGroupKeys(ExprEvaluatorContext exprEvaluatorContext)
Object	getValue(int column, int agentInstanceId, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext)
boolean	isGrouped()
void	setCurrentAccess(Object groupKey, int agentInstanceId, AggregationGroupByRollupLevel rollupLevel)	Set the current aggregation state row - for use when evaluation nodes are asked to evaluate.
void	setRemovedCallback(AggregationRowRemovedCallback callback)
void	stop()	Stops the underlying resources.

Methods inherited from class java.lang.Object

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

Field Details

INSTANCE

public static final AggregationServiceNull INSTANCE

Method Details

applyEnter

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

Description copied from interface: AggregationService

Apply events as entering a window (new events).

Specified by:

applyEnter in interface AggregationService

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

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

Description copied from interface: AggregationService

Apply events as leaving a window (old events).

Specified by:

applyLeave in interface AggregationService

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

setCurrentAccess

public void setCurrentAccess(Object groupKey,
 int agentInstanceId,
 AggregationGroupByRollupLevel rollupLevel)

Description copied from interface: AggregationResultFuture

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

Specified by:

setCurrentAccess in interface AggregationResultFuture

Parameters:

groupKey - - single key identifying the row of aggregation states

agentInstanceId - context partition id

rollupLevel - rollup level

getValue

public Object getValue(int column,
 int agentInstanceId,
 EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext exprEvaluatorContext)

Specified by:

getValue in interface AggregationResultFuture

getCollectionOfEvents

public Collection<EventBean> getCollectionOfEvents(int column,
 EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext context)

Specified by:

getCollectionOfEvents in interface AggregationResultFuture

getCollectionScalar

public Collection<Object> getCollectionScalar(int column,
 EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext context)

Specified by:

getCollectionScalar in interface AggregationResultFuture

getEventBean

public EventBean getEventBean(int column,
 EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext context)

Specified by:

getEventBean in interface AggregationResultFuture

clearResults

public void clearResults(ExprEvaluatorContext exprEvaluatorContext)

Description copied from interface: AggregationService

Clear current aggregation state.

Specified by:

clearResults in interface AggregationService

Parameters:

exprEvaluatorContext - context

setRemovedCallback

public void setRemovedCallback(AggregationRowRemovedCallback callback)

Specified by:

setRemovedCallback in interface AggregationService

accept

public void accept(AggregationServiceVisitor visitor)

Specified by:

accept in interface AggregationService

acceptGroupDetail

public void acceptGroupDetail(AggregationServiceVisitorWGroupDetail visitor)

Specified by:

acceptGroupDetail in interface AggregationService

isGrouped

public boolean isGrouped()

Specified by:

isGrouped in interface AggregationService

getGroupKey

public Object getGroupKey(int agentInstanceId)

Specified by:

getGroupKey in interface AggregationResultFuture

getGroupKeys

public Collection<Object> getGroupKeys(ExprEvaluatorContext exprEvaluatorContext)

Specified by:

getGroupKeys in interface AggregationResultFuture

stop

public void stop()

Description copied from interface: StopCallback

Stops the underlying resources.

Specified by:

stop in interface StopCallback

getContextPartitionAggregationService

public AggregationService getContextPartitionAggregationService(int agentInstanceId)

Specified by:

getContextPartitionAggregationService in interface AggregationResultFuture

getAggregationRow

public AggregationRow getAggregationRow(int agentInstanceId,
 EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext exprEvaluatorContext)

Specified by:

getAggregationRow in interface AggregationResultFuture