com.espertech.esper.epl.lookup

Class SubordTableLookupStrategyNullRow

java.lang.Object

com.espertech.esper.epl.lookup.SubordTableLookupStrategyNullRow

All Implemented Interfaces:

SubordTableLookupStrategy

public class SubordTableLookupStrategyNullRow
extends Object
implements SubordTableLookupStrategy

Implementation for a table lookup strategy that returns exactly one row but leaves that row as an undefined value.

Constructor Summary

Constructors

Constructor and Description
SubordTableLookupStrategyNullRow()

Method Summary

Modifier and Type	Method and Description
LookupStrategyDesc	getStrategyDesc()
Set<EventBean>	lookup(EventBean[] events, ExprEvaluatorContext context) Returns matched events for a set of events to look up for.
String	toQueryPlan()

Methods inherited from class java.lang.Object

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

Constructor Detail

SubordTableLookupStrategyNullRow

public SubordTableLookupStrategyNullRow()

Method Detail

lookup

public Set<EventBean> lookup(EventBean[] events,
                             ExprEvaluatorContext context)

Description copied from interface: SubordTableLookupStrategy

Returns matched events for a set of events to look up for. Never returns an empty result set, always returns null to indicate no results.

Specified by:

lookup in interface SubordTableLookupStrategy

Parameters:

events - to look up

context - context

Returns:

set of matching events, or null if none matching

toQueryPlan

public String toQueryPlan()

Specified by:

toQueryPlan in interface SubordTableLookupStrategy

getStrategyDesc

public LookupStrategyDesc getStrategyDesc()

Specified by:

getStrategyDesc in interface SubordTableLookupStrategy