org.wso2.siddhi.core.query.selector.attribute.aggregator

Class AttributeAggregator

java.lang.Object

org.wso2.siddhi.core.query.selector.attribute.aggregator.AttributeAggregator

All Implemented Interfaces:

Snapshotable

Direct Known Subclasses:

AvgAttributeAggregator, CountAttributeAggregator, DistinctCountAttributeAggregator, MaxAttributeAggregator, MaxForeverAttributeAggregator, MinAttributeAggregator, MinForeverAttributeAggregator, StdDevAttributeAggregator, SumAttributeAggregator

public abstract class AttributeAggregator
extends Object
implements Snapshotable

Abstract parent class for attribute aggregators. Attribute aggregators are used to perform aggregate operations such as count, average, etc.

Field Summary

Fields

Modifier and Type	Field and Description
protected ExpressionExecutor[]	attributeExpressionExecutors
protected String	elementId
protected SiddhiAppContext	siddhiAppContext

Constructor Summary

Constructors

Constructor and Description
AttributeAggregator()

Method Summary

Modifier and Type	Method and Description
abstract boolean	canDestroy()
AttributeAggregator	cloneAggregator(String key)
String	getElementId()
abstract org.wso2.siddhi.query.api.definition.Attribute.Type	getReturnType()
protected abstract void	init(ExpressionExecutor[] attributeExpressionExecutors, ConfigReader configReader, SiddhiAppContext siddhiAppContext) The initialization method for FunctionExecutor
void	initAggregator(ExpressionExecutor[] attributeExpressionExecutors, SiddhiAppContext siddhiAppContext, ConfigReader configReader)
Object	process(ComplexEvent event)
abstract Object	processAdd(Object data)
abstract Object	processAdd(Object[] data)
abstract Object	processRemove(Object data)
abstract Object	processRemove(Object[] data)
abstract Object	reset()

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.wso2.siddhi.core.util.snapshot.Snapshotable

currentState, restoreState

Field Detail

attributeExpressionExecutors

protected ExpressionExecutor[] attributeExpressionExecutors

siddhiAppContext

protected SiddhiAppContext siddhiAppContext

elementId

protected String elementId

Constructor Detail

AttributeAggregator

public AttributeAggregator()

Method Detail

initAggregator

public void initAggregator(ExpressionExecutor[] attributeExpressionExecutors,
                           SiddhiAppContext siddhiAppContext,
                           ConfigReader configReader)

cloneAggregator

public AttributeAggregator cloneAggregator(String key)

process

public Object process(ComplexEvent event)

init

protected abstract void init(ExpressionExecutor[] attributeExpressionExecutors,
                             ConfigReader configReader,
                             SiddhiAppContext siddhiAppContext)

The initialization method for FunctionExecutor

Parameters:

attributeExpressionExecutors - are the executors of each attributes in the function

configReader - this hold the AttributeAggregator extensions configuration reader.

siddhiAppContext - Siddhi app runtime context

getReturnType

public abstract org.wso2.siddhi.query.api.definition.Attribute.Type getReturnType()

processAdd

public abstract Object processAdd(Object data)

processAdd

public abstract Object processAdd(Object[] data)

processRemove

public abstract Object processRemove(Object data)

processRemove

public abstract Object processRemove(Object[] data)

canDestroy

public abstract boolean canDestroy()

reset

public abstract Object reset()

getElementId

public String getElementId()

Specified by:

getElementId in interface Snapshotable