com.espertech.esper.pattern

Class EvalGuardStateNode

java.lang.Object

com.espertech.esper.pattern.EvalStateNode

com.espertech.esper.pattern.EvalGuardStateNode

All Implemented Interfaces:

Evaluator, Quitable

public class EvalGuardStateNode
extends EvalStateNode
implements Evaluator, Quitable

This class represents the state of a "within" operator in the evaluation state tree. The within operator applies to a subexpression and is thus expected to only have one child node.

Field Summary

Fields

Modifier and Type	Field and Description
protected EvalStateNode	activeChildNode
protected MatchedEventMap	beginState
protected EvalGuardNode	evalGuardNode
protected Guard	guard

Constructor Summary

Constructors

Constructor and Description
EvalGuardStateNode(Evaluator parentNode, EvalGuardNode evalGuardNode) Constructor.

Method Summary

Modifier and Type	Method and Description
void	accept(EvalStateNodeVisitor visitor) Accept a visitor.
void	evaluateFalse(EvalStateNode fromNode, boolean restartable) Indicate a change in truth value to false.
void	evaluateTrue(MatchedEventMap matchEvent, EvalStateNode fromNode, boolean isQuitted) Indicate a change in truth value to true.
PatternAgentInstanceContext	getContext() Retains the pattern context with relevant pattern and statement-level services.
EvalNode	getFactoryNode() Returns the factory node for the state node.
void	guardQuit() Indicate guard quitted.
boolean	isFilterChildNonQuitting()
boolean	isFilterStateNode()
boolean	isNotOperator()
boolean	isObserverStateNodeNonRestarting()
void	quit() Stops the event expression or an instance of it.
void	removeMatch(Set<EventBean> matchEvent) Remove matches that overlap with the provided events.
void	start(MatchedEventMap beginState) Starts the event expression or an instance of it.
String	toString()

Methods inherited from class com.espertech.esper.pattern.EvalStateNode

getParentEvaluator, setParentEvaluator

Methods inherited from class java.lang.Object

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

Field Detail

evalGuardNode

protected EvalGuardNode evalGuardNode

activeChildNode

protected EvalStateNode activeChildNode

guard

protected Guard guard

beginState

protected MatchedEventMap beginState

Constructor Detail

EvalGuardStateNode

public EvalGuardStateNode(Evaluator parentNode,
                          EvalGuardNode evalGuardNode)

Constructor.

Parameters:

parentNode - is the parent evaluator to call to indicate truth value

evalGuardNode - is the factory node associated to the state

Method Detail

removeMatch

public void removeMatch(Set<EventBean> matchEvent)

Description copied from class: EvalStateNode

Remove matches that overlap with the provided events.

Specified by:

removeMatch in class EvalStateNode

Parameters:

matchEvent - set of events to check for

getFactoryNode

public EvalNode getFactoryNode()

Description copied from class: EvalStateNode

Returns the factory node for the state node.

Specified by:

getFactoryNode in class EvalStateNode

Returns:

factory node

getContext

public PatternAgentInstanceContext getContext()

Description copied from interface: Quitable

Retains the pattern context with relevant pattern and statement-level services.

The pattern context is the same context as provided to the guard factory and is provided by the quitable so the guard instance does not need to retain the pattern context.

Specified by:

getContext in interface Quitable

Returns:

pattern context

start

public void start(MatchedEventMap beginState)

Description copied from class: EvalStateNode

Starts the event expression or an instance of it. Child classes are expected to initialize and start any event listeners or schedule any time-based callbacks as needed.

Specified by:

start in class EvalStateNode

Parameters:

beginState - begin state

evaluateTrue

public final void evaluateTrue(MatchedEventMap matchEvent,
                               EvalStateNode fromNode,
                               boolean isQuitted)

Description copied from interface: Evaluator

Indicate a change in truth value to true.

Specified by:

evaluateTrue in interface Evaluator

Parameters:

matchEvent - is the container for events that caused the change in truth value

fromNode - is the node that indicates the change

isQuitted - is an indication of whether the node continues listenening or stops listening

evaluateFalse

public final void evaluateFalse(EvalStateNode fromNode,
                                boolean restartable)

Description copied from interface: Evaluator

Indicate a change in truth value to false.

Specified by:

evaluateFalse in interface Evaluator

Parameters:

fromNode - is the node that indicates the change

restartable - whether the evaluator can be restarted

quit

public final void quit()

Description copied from class: EvalStateNode

Stops the event expression or an instance of it. Child classes are expected to free resources and stop any event listeners or remove any time-based callbacks.

Specified by:

quit in class EvalStateNode

accept

public final void accept(EvalStateNodeVisitor visitor)

Description copied from class: EvalStateNode

Accept a visitor. Child classes are expected to invoke the visit method on the visitor instance passed in.

Specified by:

accept in class EvalStateNode

Parameters:

visitor - on which the visit method is invoked by each node

toString

public final String toString()

Overrides:

toString in class Object

isNotOperator

public boolean isNotOperator()

Specified by:

isNotOperator in class EvalStateNode

isFilterStateNode

public boolean isFilterStateNode()

Specified by:

isFilterStateNode in class EvalStateNode

isFilterChildNonQuitting

public boolean isFilterChildNonQuitting()

Specified by:

isFilterChildNonQuitting in interface Evaluator

isObserverStateNodeNonRestarting

public boolean isObserverStateNodeNonRestarting()

Specified by:

isObserverStateNodeNonRestarting in class EvalStateNode

guardQuit

public void guardQuit()

Description copied from interface: Quitable

Indicate guard quitted.

Specified by:

guardQuit in interface Quitable