com.espertech.esper.client.hook
Interface AggregationFunctionFactory

public interface AggregationFunctionFactory

Interface to implement for factories of aggregation functions.

Method Summary

java.lang.Class	getValueType() Returns the type of the current value.
AggregationMethod	newAggregator() Make a new, initalized aggregation state.
void	setFunctionName(java.lang.String functionName) Sets the EPL function name assigned to the factory.
void	validate(AggregationValidationContext validationContext) Implemented by plug-in aggregation functions to allow such functions to validate the type of values passed to the function at statement compile time and to generally interrogate parameter expressions.

Method Detail

setFunctionName

void setFunctionName(java.lang.String functionName)

Sets the EPL function name assigned to the factory.

Parameters:

functionName - assigned

validate

void validate(AggregationValidationContext validationContext)

Implemented by plug-in aggregation functions to allow such functions to validate the type of values passed to the function at statement compile time and to generally interrogate parameter expressions.

Parameters:

validationContext - expression information

newAggregator

AggregationMethod newAggregator()

Make a new, initalized aggregation state.

Returns:

initialized aggregator

getValueType

java.lang.Class getValueType()

Returns the type of the current value.

Returns:

type of value returned by the aggregation methods