com.espertech.esper.epl.agg.access
Class AggregationStateImpl

java.lang.Object
  com.espertech.esper.epl.agg.access.AggregationStateImpl

All Implemented Interfaces:

AggregationState, AggregationStateLinear, AggregationStateWithSize

public class AggregationStateImpl
extends java.lang.Object
implements AggregationStateWithSize, AggregationStateLinear

Implementation of access function for single-stream (not joins).

Field Summary

protected java.util.ArrayList<EventBean>	events
protected int	streamId

Constructor Summary

AggregationStateImpl(int streamId)
Ctor.

Method Summary

void	applyEnter(EventBean[] eventsPerStream, ExprEvaluatorContext exprEvaluatorContext) Enter an event.
void	applyLeave(EventBean[] eventsPerStream, ExprEvaluatorContext exprEvaluatorContext) Remove an event.
void	clear() Clear all events in the group.
java.util.Collection<EventBean>	collectionReadOnly() Returns all events for the group.
EventBean	getFirstNthValue(int index) Counting from the first element to the last, returns the oldest (first) value entered for index zero and the n-th oldest value for index N.
EventBean	getFirstValue() Returns the first (oldest) value entered.
EventBean	getLastNthValue(int index) Counting from the last element to the first, returns the newest (last) value entered for index zero and the n-th newest value for index N.
EventBean	getLastValue() Returns the newest (last) value entered.
java.util.Iterator<EventBean>	iterator() Returns all events for the group.
int	size() Must return the number of events currently held, if applicable.

Methods inherited from class java.lang.Object

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

Field Detail

streamId

protected int streamId

events

protected java.util.ArrayList<EventBean> events

Constructor Detail

AggregationStateImpl

public AggregationStateImpl(int streamId)

Ctor.

Parameters:

streamId - stream id

Method Detail

clear

public void clear()

Description copied from interface: AggregationState

Clear all events in the group.

Specified by:

clear in interface AggregationState

applyLeave

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

Description copied from interface: AggregationState

Remove an event.

Specified by:

applyLeave in interface AggregationState

Parameters:

eventsPerStream - all events in all streams, typically implementations pick the relevant stream's events to remove

exprEvaluatorContext - expression eval context

applyEnter

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

Description copied from interface: AggregationState

Enter an event.

Specified by:

applyEnter in interface AggregationState

Parameters:

eventsPerStream - all events in all streams, typically implementations pick the relevant stream's events to add

exprEvaluatorContext - expression eval context

getFirstNthValue

public EventBean getFirstNthValue(int index)

Description copied from interface: AggregationStateLinear

Counting from the first element to the last, returns the oldest (first) value entered for index zero and the n-th oldest value for index N.

Specified by:

getFirstNthValue in interface AggregationStateLinear

Parameters:

index - index

Returns:

last value

getLastNthValue

public EventBean getLastNthValue(int index)

Description copied from interface: AggregationStateLinear

Counting from the last element to the first, returns the newest (last) value entered for index zero and the n-th newest value for index N.

Specified by:

getLastNthValue in interface AggregationStateLinear

Parameters:

index - index

Returns:

last value

getFirstValue

public EventBean getFirstValue()

Description copied from interface: AggregationStateLinear

Returns the first (oldest) value entered.

Specified by:

getFirstValue in interface AggregationStateLinear

Returns:

first value

getLastValue

public EventBean getLastValue()

Description copied from interface: AggregationStateLinear

Returns the newest (last) value entered.

Specified by:

getLastValue in interface AggregationStateLinear

Returns:

last value

iterator

public java.util.Iterator<EventBean> iterator()

Description copied from interface: AggregationStateLinear

Returns all events for the group.

Specified by:

iterator in interface AggregationStateLinear

Returns:

group event iterator

collectionReadOnly

public java.util.Collection<EventBean> collectionReadOnly()

Description copied from interface: AggregationStateLinear

Returns all events for the group.

Specified by:

collectionReadOnly in interface AggregationStateLinear

Returns:

group event iterator

size

public int size()

Description copied from interface: AggregationStateWithSize

Must return the number of events currently held, if applicable. Return -1 if not applicable.

Specified by:

size in interface AggregationStateLinear

Specified by:

size in interface AggregationStateWithSize

Returns:

number of events