com.espertech.esper.epl.core
Class SelectExprEvalProcessor

java.lang.Object
  extended by com.espertech.esper.epl.core.SelectExprEvalProcessor
All Implemented Interfaces:
SelectExprProcessor

public class SelectExprEvalProcessor
extends Object
implements SelectExprProcessor

Processor for select-clause expressions that handles a list of selection items represented by expression nodes. Computes results based on matching events.


Constructor Summary
SelectExprEvalProcessor(List<SelectClauseExprCompiledSpec> selectionList, InsertIntoDesc insertIntoDesc, boolean isUsingWildcard, StreamTypeService typeService, EventAdapterService eventAdapterService)
          Ctor.
 
Method Summary
 EventType getResultEventType()
          Returns the event type that represents the select-clause items.
 EventBean process(EventBean[] eventsPerStream, boolean isNewData, boolean isSynthesize)
          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

SelectExprEvalProcessor

public SelectExprEvalProcessor(List<SelectClauseExprCompiledSpec> selectionList,
                               InsertIntoDesc insertIntoDesc,
                               boolean isUsingWildcard,
                               StreamTypeService typeService,
                               EventAdapterService eventAdapterService)
                        throws ExprValidationException
Ctor.

Parameters:
selectionList - - list of select-clause items
insertIntoDesc - - descriptor for insert-into clause contains column names overriding select clause names
isUsingWildcard - - true if the wildcard (*) appears in the select clause
typeService - -service for information about streams
eventAdapterService - - service for generating events and handling event types
Throws:
ExprValidationException - thrown if any of the expressions don't validate
Method Detail

process

public EventBean process(EventBean[] eventsPerStream,
                         boolean isNewData,
                         boolean isSynthesize)
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
Returns:
event with properties containing selected items

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

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