Represents a state machine. More...

Inheritance diagram for NSFStateMachine:

Public Member Functions
	NSFStateMachine (NSFString name, NSFEventThread thread)
	Creates a state machine More...

	NSFStateMachine (NSFString name, NSFRegion parentRegion)
	Creates a state machine. More...

	NSFStateMachine (NSFString name, NSFCompositeState parentState)
	Creates a state machine. More...

bool	Never (NSFStateMachineContext context)
	Provides a syntactical method for specifying "Never" as a transition guard, effectively blocking the transition from ever occuring. More...

void	forceStateMachineEvaluation ()
	Forces the state machine to evaluate transitions. More...

NSFEventStatus	handleEvent (NSFEvent nsfEvent)
	Handles an event. More...

void	queueEvent (NSFEvent nsfEvent)
	Queues an event for the handler. More...

void	queueEvent (NSFEvent nsfEvent, INSFNamedObject source)
	Queues an event for the handler. More...

void	resetStateMachine ()
	Resets the state machine back to its initial default state. More...

void	startEventHandler ()
	Starts event processing. More...

void	stopEventHandler ()
	Stops event processing. More...

void	startStateMachine ()

void	stopStateMachine ()

void	terminate (bool waitForTerminated)
	Terminates the event handler, so that it can be garbage collected. More...

Public Member Functions inherited from NSFCompositeState
	NSFCompositeState (NSFString name, NSFRegion parentRegion, NSFVoidAction< NSFStateMachineContext > entryAction, NSFVoidAction< NSFStateMachineContext > exitAction)
	Creates a composite state. More...

	NSFCompositeState (NSFString name, NSFCompositeState parentState, NSFVoidAction< NSFStateMachineContext > entryAction, NSFVoidAction< NSFStateMachineContext > exitAction)
	Creates a composite state. More...

override bool	isInState (NSFState state)
	Indicates if the specified state is active, i.e. is "in" the specified state. More...

override bool	isInState (NSFString stateName)
	Indicates if the specified state is active, i.e. is "in" the specified state. More...

Public Member Functions inherited from NSFState
	NSFState (NSFString name, NSFRegion parentRegion, NSFVoidAction< NSFStateMachineContext > entryAction, NSFVoidAction< NSFStateMachineContext > exitAction)
	Creates a state. More...

	NSFState (NSFString name, NSFCompositeState parentState, NSFVoidAction< NSFStateMachineContext > entryAction, NSFVoidAction< NSFStateMachineContext > exitAction)
	Creates a state. More...

bool	isActive ()
	Indicates if the state is currently active. More...

Public Member Functions inherited from NSFTaggedObject
	NSFTaggedObject (NSFString name)
	Creates an object with a unique id and a name. More...

Public Member Functions inherited from NSFUniquelyNumberedObject
	NSFUniquelyNumberedObject ()
	Creates a uniquely numbered object. More...

bool	isSameObject (NSFUniquelyNumberedObject other)
	Checks if this object is the same as another object. More...

Public Attributes
NSFVoidActions < NSFExceptionContext >	ExceptionActions = new NSFVoidActions<NSFExceptionContext>()
	Actions to execute if an exception is encountered by the state machine. More...

NSFVoidActions < NSFStateMachineContext >	StateChangeActions = new NSFVoidActions<NSFStateMachineContext>()
	Actions to execute whenever a new state is entered. More...

NSFVoidActions < NSFStateMachineContext >	ConsecutiveLoopLimitActions = new NSFVoidActions<NSFStateMachineContext>()
	Actions to execute if consecutive loop limit is reached. More...

NSFVoidActions < NSFStateMachineContext >	EventLimitActions = new NSFVoidActions<NSFStateMachineContext>()
	Actions to execute if consecutive loop limit is reached. More...

Public Attributes inherited from NSFState
NSFVoidActions < NSFStateMachineContext >	EntryActions = new NSFVoidActions<NSFStateMachineContext>()
	Actions to be executed whenever the state is entered. More...

NSFVoidActions < NSFStateMachineContext >	ExitActions = new NSFVoidActions<NSFStateMachineContext>()
	Actions to be executed whenever the state is exited. More...

Protected Member Functions
bool	hasEvent (NSFEvent nsfEvent)
	Checks if an event is queued for processing. More...

bool	isTopStateMachine ()
	Checks if the state machine is the top state machine in a nested heirarchy. More...

void	rerouteTransition (NSFTransition transition, NSFState source, NSFState target)
	Re-routes a transition between a specified source and destination More...

Properties
bool	ConsecutiveLoopDetectionEnabled `[get, set]`
	Gets or sets the flag indicating if consecutive loop detection is enabled. More...

int	ConsecutiveLoopLimit `[get, set]`
	Gets or sets the maximum number of transitions without a pause allowed by consecutive loop detection. More...

bool	EventLimitDetectionEnabled `[get, set]`
	Gets or sets the flag indicating if event limit detection is enabled. More...

int	EventLimit `[get, set]`
	Gets or sets the maximum number of transitions without a pause allowed by consecutive loop detection. More...

NSFBoolGuard < NSFStateMachineContext >	Else `[get]`
	Provides a syntactical method for specifying "Else" as a transition guard. More...

NSFEventThread	EventThread `[get, set]`
	Gets or sets the state machine's event thread. More...

Int32	QueuedEvents `[get, set]`
	Gets or sets the number of events currently queued in state machine's event thread. More...

bool	LoggingEnabled `[get, set]`
	Gets or sets the flag indicating if state machine event logging is enabled. More...

NSFEventHandlerRunStatus	RunStatus `[get, set]`

NSFEventHandlerTerminationStatus	TerminationStatus `[get, set]`

static uint	TerminationSleepTime `[get, set]`
	Gets the amount of time (mS) the terminate method sleeps between checks for state machine termination. More...

static int	TerminationTimeout `[get, set]`
	The amount of time the terminate method will wait for event processing to complete. More...

override NSFStateMachine	TopStateMachine `[get]`

Properties inherited from NSFState
bool	LogEntry `[get, set]`
	Gets or sets the flag indicating if trace logging is enabled or disabled for the state. More...

virtual NSFStateMachine	TopStateMachine `[get]`
	Gets the top state machine encompassing the state. More...

Properties inherited from NSFTaggedObject
NSFString	Name `[get, set]`

Properties inherited from NSFUniquelyNumberedObject
NSFId	UniqueId `[get]`
	Gets or sets the unique id of the object. More...

Properties inherited from INSFNamedObject
NSFString	Name `[get]`
	Gets the name of the object. More...

Properties inherited from INSFEventHandler
NSFEventHandlerRunStatus	RunStatus `[get]`
	Gets the run status of the event handler. More...

NSFEventHandlerTerminationStatus	TerminationStatus `[get]`
	Gets the termination status of the event handler. More...

Additional Inherited Members
Static Public Member Functions inherited from NSFUniquelyNumberedObject
static NSFId	getNextUniqueId ()
	Gets the next unique id. More...

Detailed Description

Represents a state machine.

Constructor & Destructor Documentation

NSFStateMachine	(	NSFString	name,
		NSFEventThread	thread
	)

Creates a state machine

Parameters

name	The user defined name for the state machine.
thread	The thread on which events for the state machine are queued.

NSFStateMachine	(	NSFString	name,
		NSFRegion	parentRegion
	)

Creates a state machine.

Parameters

name	The user defined name for the state machine.
parentRegion	The parent region of the state machine.

NSFStateMachine	(	NSFString	name,
		NSFCompositeState	parentState
	)

Creates a state machine.

Parameters

name	The user defined name for the state machine.
parentState	The parent composite state for the state machine.

Member Function Documentation

void forceStateMachineEvaluation ( )

Forces the state machine to evaluate transitions.

This method is rarely needed, but can be used, for example, to force evaluation if a guard condition has changed.

NSFEventStatus handleEvent ( NSFEvent nsfEvent )

Handles an event.

Parameters

nsfEvent The event to handle.

Returns: Status indicating if the event was handled or not.

This method is for use only by the North State Framework's internal logic. It processes the event using UML defined behavior, including run to completion.

Implements INSFEventHandler.

bool hasEvent ( NSFEvent nsfEvent )

protected

Checks if an event is queued for processing.

Parameters

nsfEvent The event in queustion.

Returns: True if the event is the in queue, otherwise false.

bool isTopStateMachine ( )

protected

Checks if the state machine is the top state machine in a nested heirarchy.

Returns: True if the state machine is the top state machine, otherwise false.

bool Never ( NSFStateMachineContext context )

Provides a syntactical method for specifying "Never" as a transition guard, effectively blocking the transition from ever occuring.

void queueEvent ( NSFEvent nsfEvent )

Queues an event for the handler.

Parameters

nsfEvent The event to queue.

Implements INSFEventHandler.

void queueEvent	(	NSFEvent	nsfEvent,
		INSFNamedObject	source
	)

Queues an event for the handler.

Parameters

nsfEvent	The event to queue.
source	The source of the event.

Implements INSFEventHandler.

void rerouteTransition	(	NSFTransition	transition,
		NSFState	source,
		NSFState	target
	)

protected

Re-routes a transition between a specified source and destination

Parameters

transition	The transition to re-route.
source	The new source for the transition.
target	The new target for the transition.

This method can be used when extending state machines. Careful design consideration should be made before using this method. Never change a state machines structure while it is running.

void resetStateMachine ( )

Resets the state machine back to its initial default state.

If the state machine is currently running (started), it will process all events currently in its queue before resetting and it will continue running after the reset. If the state machine is currently stopped, it will continue to be stopped after the reset. While a state machine is stopped, all events are dropped from its queue.

void startEventHandler ( )

Starts event processing.

When stopped, events queued prior to calling the method startEventHandler() will be dropped. Events queued after calling the method startEventHandler() will be processed, until the next call to stopEventHandler(). When started, events queued prior to calling the method stopEventHandler() will be processed. Events queued after calling the method stopEventHandler() will be dropped, until the next call to startEventHandler().

Implements INSFEventHandler.

void startStateMachine ( )

void stopEventHandler ( )

Stops event processing.

When stopped, events queued prior to calling the method startEventHandler() will be dropped. Events queued after calling the method startEventHandler() will be processed, until the next call to stopEventHandler(). When started, events queued prior to calling the method stopEventHandler() will be processed. Events queued after calling the method stopEventHandler() will be dropped, until the next call to startEventHandler().

Implements INSFEventHandler.

void stopStateMachine ( )

void terminate ( bool waitForTerminated )

Terminates the event handler, so that it can be garbage collected.

Parameters

waitForTerminated Flag indicating if the method should wait until the event handler is terminated (true), or if it should return immediately (false).

This method terminates the event handler in a coordinated fashion, making sure all remaining events are cleared, so that it can be garbage collected. After calling this method, the event handler cannot be restarted. This method should only be called if the event handler should be garbage collected. If the waitForTerminated flag is set true, this method must not be called from the event handler's thread of execution.

Implements INSFEventHandler.

Member Data Documentation

NSFVoidActions<NSFStateMachineContext> ConsecutiveLoopLimitActions = new NSFVoidActions<NSFStateMachineContext>()

Actions to execute if consecutive loop limit is reached.

State machines have the ability to detect if they are ill-formed by way of consecutive loop detection. This mechanism looks for repeated transitions without a pause (as defined by the condition when there are no more events queued to the state machine, and the final run-to-completion step has occurred). If more than the specified number of transitions occur without a pause, the state machine will remove its queued events, call the consecutive loop limit actions, and stop after executing any events queued by the limit actions.

NSFVoidActions<NSFStateMachineContext> EventLimitActions = new NSFVoidActions<NSFStateMachineContext>()

Actions to execute if consecutive loop limit is reached.

State machines have the ability to detect if they are not processing messages in a timely fashion by way of event limit detection. This mechanism looks at the number of events in the state machine's event queue. If the more than the specified number of events are queued, the state machine will remove its queued events, call the event limit actions, and stop after executing any events queued by the limit actions.

NSFVoidActions<NSFExceptionContext> ExceptionActions = new NSFVoidActions<NSFExceptionContext>()

Actions to execute if an exception is encountered by the state machine.

NSFVoidActions<NSFStateMachineContext> StateChangeActions = new NSFVoidActions<NSFStateMachineContext>()

Actions to execute whenever a new state is entered.

Property Documentation

bool ConsecutiveLoopDetectionEnabled

getset

Gets or sets the flag indicating if consecutive loop detection is enabled.

State machines have the ability to detect if they are ill-formed by way of consecutive loop detection. This mechanism looks for repeated transitions without a pause (as defined by the condition when there are no more events queued to the state machine, and the final run-to-completion step has occurred). If more than the specified number of transitions occur without a pause, the state machine will remove its queued events, call the consecutive loop limit actions, and stop after executing any events queued by the actions.

int ConsecutiveLoopLimit

getset

Gets or sets the maximum number of transitions without a pause allowed by consecutive loop detection.

State machines have the ability to detect if they are ill-formed by way of consecutive loop detection. This mechanism looks for repeated transitions without a pause (as defined by the condition when there are no more events queued to the state machine, and the final run-to-completion step has occurred). If more than the specified number of transitions occur without a pause, the state machine will remove its queued events, call the consecutive loop limit actions, and stop after executing any events queued by the actions.

NSFBoolGuard<NSFStateMachineContext> Else

get

Provides a syntactical method for specifying "Else" as a transition guard.

int EventLimit

getset

Gets or sets the maximum number of transitions without a pause allowed by consecutive loop detection.

State machines have the ability to detect if they are not processing messages in a timely fashion by way of event limit detection. This mechanism looks at the number of events in the state machine's event queue. If the more than the specified number of events are queued, the state machine will remove its queued events, call the event limit actions, and stop after executing any events queued by the limit actions.

bool EventLimitDetectionEnabled

getset

Gets or sets the flag indicating if event limit detection is enabled.

State machines have the ability to detect if they are not processing messages in a timely fashion by way of event limit detection. This mechanism looks at the number of events in the state machine's event queue. If the more than the specified number of events are queued, the state machine will remove its queued events, call the event limit actions, and stop after executing any events queued by the limit actions.

NSFEventThread EventThread

getset

Gets or sets the state machine's event thread.

bool LoggingEnabled

getset

Gets or sets the flag indicating if state machine event logging is enabled.

Int32 QueuedEvents

getset

Gets or sets the number of events currently queued in state machine's event thread.

This mechanism only works if events are queued throught the state machine's queueEvent methods.

NSFEventHandlerRunStatus RunStatus

getset

uint TerminationSleepTime

staticgetset

Gets the amount of time (mS) the terminate method sleeps between checks for state machine termination.

NSFEventHandlerTerminationStatus TerminationStatus

getset

int TerminationTimeout

staticgetset

The amount of time the terminate method will wait for event processing to complete.

override NSFStateMachine TopStateMachine

get

Public Member Functions

Public Attributes

Protected Member Functions

Properties

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

Property Documentation

Copyright 2004-2014, North State Software, LLC. All rights reserved.