com.espertech.esper.epl.agg.access

Class AggregationAccessorFirstNoEval

java.lang.Object

com.espertech.esper.epl.agg.access.AggregationAccessorFirstNoEval

All Implemented Interfaces:

AggregationAccessor

public class AggregationAccessorFirstNoEval
extends Object
implements AggregationAccessor

Represents the aggregation accessor that provides the result for the "first" aggregation function without index.

Field Summary

Fields

Modifier and Type	Field and Description
static AggregationAccessorFirstNoEval	INSTANCE

Constructor Summary

Constructors

Constructor and Description
AggregationAccessorFirstNoEval()

Method Summary

Modifier and Type	Method and Description
EventBean	getEnumerableEvent(AggregationState state, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext) Return the aggregation state value consisting of a single event.
Collection<EventBean>	getEnumerableEvents(AggregationState state, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext) Return the aggregation state value consisting of a collection of events.
Collection<Object>	getEnumerableScalar(AggregationState state, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext) Return the aggregation state value consisting of a collection of scalar values.
Object	getValue(AggregationState state, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext) Return the aggregation state value either as a scalar value or any other object.

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final AggregationAccessorFirstNoEval INSTANCE

Constructor Detail

AggregationAccessorFirstNoEval

public AggregationAccessorFirstNoEval()

Method Detail

getValue

public Object getValue(AggregationState state,
                       EventBean[] eventsPerStream,
                       boolean isNewData,
                       ExprEvaluatorContext exprEvaluatorContext)

Description copied from interface: AggregationAccessor

Return the aggregation state value either as a scalar value or any other object.

For enumeration over scalar values or objects return an array or collection of scalar or object values.

Use the #getEnumerableEvents method to return a collection of events.

Use the #getEnumerableEvent to return a single events.

Specified by:

getValue in interface AggregationAccessor

Parameters:

state - aggregation state, downcast as needed

eventsPerStream - events

isNewData - new-data indicator

exprEvaluatorContext - eval context

Returns:

return value

getEnumerableEvents

public Collection<EventBean> getEnumerableEvents(AggregationState state,
                                                 EventBean[] eventsPerStream,
                                                 boolean isNewData,
                                                 ExprEvaluatorContext exprEvaluatorContext)

Description copied from interface: AggregationAccessor

Return the aggregation state value consisting of a collection of events.

Specified by:

getEnumerableEvents in interface AggregationAccessor

Parameters:

state - aggregation state, downcast as needed

eventsPerStream - events

isNewData - new-data indicator

exprEvaluatorContext - eval context

Returns:

return collection of events or null or empty collection

getEnumerableScalar

public Collection<Object> getEnumerableScalar(AggregationState state,
                                              EventBean[] eventsPerStream,
                                              boolean isNewData,
                                              ExprEvaluatorContext exprEvaluatorContext)

Description copied from interface: AggregationAccessor

Return the aggregation state value consisting of a collection of scalar values.

Specified by:

getEnumerableScalar in interface AggregationAccessor

Parameters:

state - aggregation state, downcast as needed

eventsPerStream - events

isNewData - new-data indicator

exprEvaluatorContext - eval context

Returns:

return collection of scalar or null or empty collection

getEnumerableEvent

public EventBean getEnumerableEvent(AggregationState state,
                                    EventBean[] eventsPerStream,
                                    boolean isNewData,
                                    ExprEvaluatorContext exprEvaluatorContext)

Description copied from interface: AggregationAccessor

Return the aggregation state value consisting of a single event.

Specified by:

getEnumerableEvent in interface AggregationAccessor

Parameters:

state - aggregation state, downcast as needed

eventsPerStream - events

isNewData - new-data indicator

exprEvaluatorContext - eval context

Returns:

return event or null