org.wso2.extension.siddhi.execution.unique

Class UniqueLengthWindowProcessor

java.lang.Object

org.wso2.siddhi.core.query.processor.stream.AbstractStreamProcessor

org.wso2.siddhi.core.query.processor.stream.window.WindowProcessor

org.wso2.extension.siddhi.execution.unique.UniqueLengthWindowProcessor

All Implemented Interfaces:

org.wso2.siddhi.core.query.processor.Processor, org.wso2.siddhi.core.query.processor.stream.window.FindableProcessor, org.wso2.siddhi.core.util.extension.holder.EternalReferencedHolder, org.wso2.siddhi.core.util.snapshot.Snapshotable

public class UniqueLengthWindowProcessor
extends org.wso2.siddhi.core.query.processor.stream.window.WindowProcessor
implements org.wso2.siddhi.core.query.processor.stream.window.FindableProcessor

Field Summary

Fields inherited from class org.wso2.siddhi.core.query.processor.stream.window.WindowProcessor

outputExpectsExpiredEvents

Fields inherited from class org.wso2.siddhi.core.query.processor.stream.AbstractStreamProcessor

additionalAttributes, attributeExpressionExecutors, attributeExpressionLength, complexEventPopulater, elementId, executionPlanContext, inputDefinition, log, nextProcessor, streamEventCloner

Constructor Summary

Constructors

Constructor and Description
UniqueLengthWindowProcessor()

Method Summary

Methods

Modifier and Type	Method and Description
org.wso2.siddhi.core.util.collection.operator.Finder	constructFinder(org.wso2.siddhi.query.api.expression.Expression expression, org.wso2.siddhi.core.util.collection.operator.MatchingMetaStateHolder matchingMetaStateHolder, org.wso2.siddhi.core.config.ExecutionPlanContext executionPlanContext, List<org.wso2.siddhi.core.executor.VariableExpressionExecutor> variableExpressionExecutors, Map<String,org.wso2.siddhi.core.table.EventTable> eventTableMap) To construct a finder having the capability of finding events at the processor that corresponds to the incoming matchingEvent and the given matching expression logic.
Object[]	currentState() Used to collect the serializable state of the processing element, that need to be persisted for the reconstructing the element to the same state on a different point of time
org.wso2.siddhi.core.event.stream.StreamEvent	find(org.wso2.siddhi.core.event.state.StateEvent matchingEvent, org.wso2.siddhi.core.util.collection.operator.Finder finder) To find events from the processor event pool, that the matches the matchingEvent based on finder logic.
protected void	init(org.wso2.siddhi.core.executor.ExpressionExecutor[] attributeExpressionExecutors, org.wso2.siddhi.core.config.ExecutionPlanContext executionPlanContext) The init method of the WindowProcessor, this method will be called before other methods
protected void	process(org.wso2.siddhi.core.event.ComplexEventChunk<org.wso2.siddhi.core.event.stream.StreamEvent> streamEventChunk, org.wso2.siddhi.core.query.processor.Processor nextProcessor, org.wso2.siddhi.core.event.stream.StreamEventCloner streamEventCloner) The main processing method that will be called upon event arrival
void	restoreState(Object[] state) Used to restore serialized state of the processing element, for reconstructing the element to the same state as if was on a previous point of time.
void	start() This will be called only once and this can be used to acquire required resources for the processing element.
void	stop() This will be called only once and this can be used to release the acquired resources for processing.

Methods inherited from class org.wso2.siddhi.core.query.processor.stream.window.WindowProcessor

init, processEventChunk

Methods inherited from class org.wso2.siddhi.core.query.processor.stream.AbstractStreamProcessor

cloneProcessor, constructStreamEventPopulater, getElementId, getNextProcessor, initProcessor, process, setNextProcessor, setStreamEventCloner, setToLast

Methods inherited from class java.lang.Object

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

Constructor Detail

UniqueLengthWindowProcessor

public UniqueLengthWindowProcessor()

Method Detail

init

protected void init(org.wso2.siddhi.core.executor.ExpressionExecutor[] attributeExpressionExecutors,
        org.wso2.siddhi.core.config.ExecutionPlanContext executionPlanContext)

The init method of the WindowProcessor, this method will be called before other methods

Specified by:

init in class org.wso2.siddhi.core.query.processor.stream.window.WindowProcessor

Parameters:

attributeExpressionExecutors - the executors of each function parameters

executionPlanContext - the context of the execution plan

process

protected void process(org.wso2.siddhi.core.event.ComplexEventChunk<org.wso2.siddhi.core.event.stream.StreamEvent> streamEventChunk,
           org.wso2.siddhi.core.query.processor.Processor nextProcessor,
           org.wso2.siddhi.core.event.stream.StreamEventCloner streamEventCloner)

The main processing method that will be called upon event arrival

Specified by:

process in class org.wso2.siddhi.core.query.processor.stream.window.WindowProcessor

Parameters:

streamEventChunk - the stream event chunk that need to be processed

nextProcessor - the next processor to which the success events need to be passed

streamEventCloner - helps to clone the incoming event for local storage or modification

start

public void start()

This will be called only once and this can be used to acquire required resources for the processing element. This will be called after initializing the system and before starting to process the events.

Specified by:

start in interface org.wso2.siddhi.core.util.extension.holder.EternalReferencedHolder

stop

public void stop()

This will be called only once and this can be used to release the acquired resources for processing. This will be called before shutting down the system.

Specified by:

stop in interface org.wso2.siddhi.core.util.extension.holder.EternalReferencedHolder

currentState

public Object[] currentState()

Used to collect the serializable state of the processing element, that need to be persisted for the reconstructing the element to the same state on a different point of time

Specified by:

currentState in interface org.wso2.siddhi.core.util.snapshot.Snapshotable

Returns:

stateful objects of the processing element as an array

restoreState

public void restoreState(Object[] state)

Used to restore serialized state of the processing element, for reconstructing the element to the same state as if was on a previous point of time.

Specified by:

restoreState in interface org.wso2.siddhi.core.util.snapshot.Snapshotable

Parameters:

state - the stateful objects of the element as an array on the same order provided by currentState().

find

public org.wso2.siddhi.core.event.stream.StreamEvent find(org.wso2.siddhi.core.event.state.StateEvent matchingEvent,
                                                 org.wso2.siddhi.core.util.collection.operator.Finder finder)

To find events from the processor event pool, that the matches the matchingEvent based on finder logic.

Specified by:

find in interface org.wso2.siddhi.core.query.processor.stream.window.FindableProcessor

Parameters:

matchingEvent - the event to be matched with the events at the processor

finder - the execution element responsible for finding the corresponding events that matches the matchingEvent based on pool of events at Processor

Returns:

the matched events

constructFinder

public org.wso2.siddhi.core.util.collection.operator.Finder constructFinder(org.wso2.siddhi.query.api.expression.Expression expression,
                                                                   org.wso2.siddhi.core.util.collection.operator.MatchingMetaStateHolder matchingMetaStateHolder,
                                                                   org.wso2.siddhi.core.config.ExecutionPlanContext executionPlanContext,
                                                                   List<org.wso2.siddhi.core.executor.VariableExpressionExecutor> variableExpressionExecutors,
                                                                   Map<String,org.wso2.siddhi.core.table.EventTable> eventTableMap)

To construct a finder having the capability of finding events at the processor that corresponds to the incoming matchingEvent and the given matching expression logic.

Specified by:

constructFinder in interface org.wso2.siddhi.core.query.processor.stream.window.FindableProcessor

Parameters:

expression - the matching expression

matchingMetaStateHolder - the meta structure of the incoming matchingEvent

executionPlanContext - current execution plan context

variableExpressionExecutors - the list of variable ExpressionExecutors already created

eventTableMap - map of event tables

Returns:

finder having the capability of finding events at the processor against the expression and incoming matchingEvent