com.espertech.esper.pattern

Class EvalStateNode

java.lang.Object

com.espertech.esper.pattern.EvalStateNode

Direct Known Subclasses:

EvalAndStateNode, EvalAuditStateNode, EvalEveryDistinctStateExpireKeyNode, EvalEveryDistinctStateNode, EvalEveryStateNode, EvalFilterStateNode, EvalFollowedByStateNode, EvalFollowedByWithMaxStateNodeManaged, EvalGuardStateNode, EvalMatchUntilStateNode, EvalNotStateNode, EvalObserverStateNode, EvalOrStateNode, EvalRootStateNode

public abstract class EvalStateNode
extends Object

Superclass of all state nodes in an evaluation node tree representing an event expressions. Follows the Composite pattern. Subclasses are expected to keep their own collection containing child nodes as needed.

Constructor Summary

Constructors

Constructor and Description
EvalStateNode(Evaluator parentNode) Constructor.

Method Summary

Modifier and Type	Method and Description
abstract void	accept(EvalStateNodeVisitor visitor) Accept a visitor.
abstract EvalNode	getFactoryNode() Returns the factory node for the state node.
Evaluator	getParentEvaluator() Returns the parent evaluator.
abstract boolean	isFilterStateNode()
abstract boolean	isNotOperator()
abstract boolean	isObserverStateNodeNonRestarting()
abstract void	quit() Stops the event expression or an instance of it.
abstract void	removeMatch(Set<EventBean> matchEvent) Remove matches that overlap with the provided events.
void	setParentEvaluator(Evaluator parentEvaluator) Sets the parent evaluator.
abstract void	start(MatchedEventMap beginState) Starts the event expression or an instance of it.

Methods inherited from class java.lang.Object

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

Constructor Detail

EvalStateNode

public EvalStateNode(Evaluator parentNode)

Constructor.

Parameters:

parentNode - is the evaluator for this node on which to indicate a change in truth value

Method Detail

start

public abstract void start(MatchedEventMap beginState)

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.

Parameters:

beginState - begin state

quit

public abstract void quit()

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.

accept

public abstract void accept(EvalStateNodeVisitor visitor)

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

Parameters:

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

getFactoryNode

public abstract EvalNode getFactoryNode()

Returns the factory node for the state node.

Returns:

factory node

isNotOperator

public abstract boolean isNotOperator()

isFilterStateNode

public abstract boolean isFilterStateNode()

isObserverStateNodeNonRestarting

public abstract boolean isObserverStateNodeNonRestarting()

removeMatch

public abstract void removeMatch(Set<EventBean> matchEvent)

Remove matches that overlap with the provided events.

Parameters:

matchEvent - set of events to check for

getParentEvaluator

public final Evaluator getParentEvaluator()

Returns the parent evaluator.

Returns:

parent evaluator instance

setParentEvaluator

public final void setParentEvaluator(Evaluator parentEvaluator)

Sets the parent evaluator.

Parameters:

parentEvaluator - for this node