com.espertech.esper.epl.core

Class SelectExprResultProcessor

java.lang.Object

com.espertech.esper.epl.core.SelectExprResultProcessor

All Implemented Interfaces:

SelectExprProcessor

public class SelectExprResultProcessor
extends Object
implements SelectExprProcessor

A select expression processor that check what type of result (synthetic and natural) event is expected and produces.

Constructor Summary

Constructors

Constructor and Description
SelectExprResultProcessor(StatementResultService statementResultService, SelectExprProcessor syntheticProcessor, BindProcessor bindProcessor) Ctor.

Method Summary

Modifier and Type	Method and Description
EventType	getResultEventType() Returns the event type that represents the select-clause items.
EventBean	process(EventBean[] eventsPerStream, boolean isNewData, boolean isSynthesize, ExprEvaluatorContext exprEvaluatorContext) Computes the select-clause results and returns an event of the result event type that contains, in it's properties, the selected items.

Methods inherited from class java.lang.Object

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

Constructor Detail

SelectExprResultProcessor

public SelectExprResultProcessor(StatementResultService statementResultService,
                                 SelectExprProcessor syntheticProcessor,
                                 BindProcessor bindProcessor)

Ctor.

Parameters:

statementResultService - for awareness of listeners and subscribers handles output results

syntheticProcessor - is the processor generating synthetic events according to the select clause

bindProcessor - for generating natural object column results

Method Detail

getResultEventType

public EventType getResultEventType()

Description copied from interface: SelectExprProcessor

Returns the event type that represents the select-clause items.

Specified by:

getResultEventType in interface SelectExprProcessor

Returns:

event type representing select-clause items

process

public EventBean process(EventBean[] eventsPerStream,
                         boolean isNewData,
                         boolean isSynthesize,
                         ExprEvaluatorContext exprEvaluatorContext)

Description copied from interface: SelectExprProcessor

Computes the select-clause results and returns an event of the result event type that contains, in it's properties, the selected items.

Specified by:

process in interface SelectExprProcessor

Parameters:

eventsPerStream - - is per stream the event

isNewData - - indicates whether we are dealing with new data (istream) or old data (rstream)

isSynthesize - - set to true to indicate that synthetic events are required for an iterator result set

exprEvaluatorContext - context

Returns:

event with properties containing selected items