OSDL::MVC::PeriodicalModel Class Reference

Event-based model, to be periodically activated by the scheduler. More...

#include <OSDLModel.h>

Inheritance diagram for OSDL::MVC::PeriodicalModel:

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Collaboration diagram for OSDL::MVC::PeriodicalModel:

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List of all members.

Public Member Functions
	PeriodicalModel (Events::Period period=1, bool autoRegister=true, Engine::ObjectSchedulingPolicy policy=Engine::relaxed, Engine::Weight weight=1)
	Constructor of an OSDL MVC model which is to be periodically scheduled.
virtual	~PeriodicalModel () throw ()
	Virtual destructor.
virtual const std::string	toString (Ceylan::VerbosityLevels level=Ceylan::high) const
	Returns an user-friendly description of the state of this object.
virtual void	registerToScheduler ()
	Registers this active object to the supposedly already existing scheduler.
virtual void	unregisterFromScheduler ()
	Unregisters this active object from the existing scheduler to whom it was supposedly registered.
virtual Events::Period	getPeriod () const
	Returns the period for this active object.
virtual void	setPeriod (Events::Period newPeriod)
	Sets a period for this object, which will be periodically scheduled accordingly.
virtual Ceylan::Maths::Hertz	setFrequency (Ceylan::Maths::Hertz newFrequency)
	Sets the period of this object so that it gets activated on specified frequency, making this object periodically activated if it was not, or changing its already defined period otherwise.
virtual Events::Period	getSubslotNumber () const
	Returns the number of the sub-slot this active object is referenced in.
virtual void	onRegistering (Events::Period subslot)
	Automatically called by the scheduler at registration time.
virtual void	setBirthTick (Events::SimulationTick currentSimulationTick)
	Sets the birth time, expressed in simulation ticks, of this active object.
virtual Events::SimulationTick	convertDurationToActivationCount (Ceylan::System::Millisecond duration) const
	Returns the number of activations of this periodical object which corresponds to the specified duration.
virtual ObjectSchedulingPolicy	getPolicy () const
	Returns the scheduling policy for this active object.
virtual Weight	getWeight () const
	Returns the average processing need for each activation of this object.
virtual Events::SimulationTick	getBirthTick () const
	Returns the birth time, expressed in simulation ticks, of this active object.
virtual void	onActivation (Events::SimulationTick newTick)=0
	Pure virtual method, which is called when this active object gets activated on behalf of the scheduler.
virtual void	onSkip (Events::SimulationTick skippedTick)
	Called whenever the scheduler had to skip a period of activation for this object.
virtual void	onImpossibleActivation (Events::SimulationTick missedTick)
	Called whenever the scheduler was unable to activate this object.
Protected Member Functions
Events::SimulationTick	getLocalTime () const
	Returns this object local time, as if the origin of time was this object creation.
Protected Attributes
Events::Period	_period
	Tells what is the requested scheduling period for this object.
Events::Period	_subslot
	Records in which sub-slot this object is stored.
ObjectSchedulingPolicy	_policy
	Determines the scheduling policy of this object.
Weight	_weight
	Describe the average processing need for each activation of this object.
bool	_registered
	Tells whether this active object has already been registered to a scheduler.
Events::SimulationTick	_birthTick
	The date of birth of this object, expressed in simulation time.

Detailed Description

Event-based model, to be periodically activated by the scheduler.

See also:: OSDL::Engine::Scheduler

Definition at line 74 of file OSDLModel.h.

Constructor & Destructor Documentation

OSDL::MVC::PeriodicalModel::PeriodicalModel	(	Events::Period	period = `1`,
		bool	autoRegister = `true`,
		Engine::ObjectSchedulingPolicy	policy = `Engine::relaxed`,
		Engine::Weight	weight = `1`
	)			`[explicit]`

Constructor of an OSDL MVC model which is to be periodically scheduled.

Parameters:

	period	tells how many simulation ticks are to be waited by the scheduler until this model is activated again. The period must not be null.
	autoRegister	tells whether this new Model is to automatically register itself to the scheduler. It requires the scheduler to exist already.
	policy	allows to choose a scheduling policy, according to the quality of service this model requires.
	weight	evaluates how much processing power an activation of this model is to cost on average. This helps the scheduler doing its job balance.

Exceptions:

Engine::SchedulingException

if the construction failed.

PeriodicalModel::~PeriodicalModel ( ) throw () [virtual]

Virtual destructor.

Note:: This model will automatically unsubscribe from the scheduler if needed.

Definition at line 66 of file OSDLModel.cc.

Member Function Documentation

OSDL::Events::SimulationTick PeriodicalActiveObject::convertDurationToActivationCount ( Ceylan::System::Millisecond duration ) const [virtual, inherited]

Returns the number of activations of this periodical object which corresponds to the specified duration.

For example a duration of 400 ms, for a periodical object whose period is 50 ms, corresponds to 8 of its simulation ticks.

Parameters:

duration

Exceptions:

SchedulingException

if the operation failed, notably if this object is not stored in a sub-slot already.

Definition at line 340 of file OSDLPeriodicalActiveObject.cc.

References OSDL::Engine::PeriodicalActiveObject::_period, OSDL::Engine::Scheduler::GetExistingScheduler(), OSDL::Engine::Scheduler::getSimulationTickCount(), and OSDL::Engine::Scheduler::getTimeSliceDuration().

SimulationTick ActiveObject::getBirthTick ( ) const [virtual, inherited]

Returns the birth time, expressed in simulation ticks, of this active object.

Definition at line 107 of file OSDLActiveObject.cc.

References OSDL::Engine::ActiveObject::_birthTick.

Referenced by OSDL::Engine::Scheduler::unregisterProgrammedObject().

Events::SimulationTick OSDL::Engine::ActiveObject::getLocalTime ( ) const [protected, inherited]

Returns this object local time, as if the origin of time was this object creation.

Period PeriodicalActiveObject::getPeriod ( ) const [virtual, inherited]

Returns the period for this active object.

Definition at line 194 of file OSDLPeriodicalActiveObject.cc.

References OSDL::Engine::PeriodicalActiveObject::_period.

Referenced by OSDL::Engine::Scheduler::registerPeriodicalObject(), and OSDL::Engine::Scheduler::unregisterPeriodicalObject().

ObjectSchedulingPolicy ActiveObject::getPolicy ( ) const [virtual, inherited]

Returns the scheduling policy for this active object.

Definition at line 80 of file OSDLActiveObject.cc.

References OSDL::Engine::ActiveObject::_policy.

Referenced by OSDL::Engine::PeriodicSlot::add().

Period PeriodicalActiveObject::getSubslotNumber ( ) const [virtual, inherited]

Returns the number of the sub-slot this active object is referenced in.

This sub-slot is set on registration: the scheduler calls the onRegistering method of this object.

Exceptions:

SchedulingException

if the operation failed, notably if this object is not stored in a sub-slot already.

Definition at line 271 of file OSDLPeriodicalActiveObject.cc.

References OSDL::Engine::PeriodicalActiveObject::_period, and OSDL::Engine::PeriodicalActiveObject::_subslot.

Weight ActiveObject::getWeight ( ) const [virtual, inherited]

Returns the average processing need for each activation of this object.

Note:: The greater the weight is, the heavier processing should be.

Definition at line 89 of file OSDLActiveObject.cc.

References OSDL::Engine::ActiveObject::_weight.

virtual void OSDL::Engine::ActiveObject::onActivation ( Events::SimulationTick newTick ) [pure virtual, inherited]

Pure virtual method, which is called when this active object gets activated on behalf of the scheduler.

Note:: This is where the objects are to live actually: their time slice is to be spent here.; If, for any reason, there is a simulation skip, this method may not be called for some objects. Refer to the onSkip method, which would be called instead (and, sadly, later).

See also:: onSkip.

virtual void OSDL::Engine::ActiveObject::onImpossibleActivation ( Events::SimulationTick missedTick ) [virtual, inherited]

Called whenever the scheduler was unable to activate this object.

This can happen for example when an absolute simulation tick is specified whereas the current time is already in its future.

Default behaviour for this method is: throw a SchedulingException.

Parameters:

missedTick

tells which tick is out of range.

Exceptions:

SchedulingException

if this active object should not stand activation failures.

void PeriodicalActiveObject::onRegistering ( Events::Period subslot ) [virtual, inherited]

Automatically called by the scheduler at registration time.

Sets the sub-slot, to ease deallocation.

Note:: Registering does not always imply object birth, as if the scheduler is not currently running, then birth will happen only when it is started.

Exceptions:

SchedulingException

if the operation failed.

Definition at line 284 of file OSDLPeriodicalActiveObject.cc.

References OSDL::Engine::ActiveObject::_registered, and OSDL::Engine::PeriodicalActiveObject::_subslot.

Referenced by OSDL::Engine::Scheduler::registerPeriodicalObject().

virtual void OSDL::Engine::ActiveObject::onSkip ( Events::SimulationTick skippedTick ) [virtual, inherited]

Called whenever the scheduler had to skip a period of activation for this object.

Default behaviour for this method is: do nothing except complain in the warning channel.

Parameters:

skippedTick

tells which tick was skipped.

Exceptions:

SchedulingException

if this active object cannot stand skipped stimulation ticks.

Note:: Some objects may call the onActivation method for the skipped tick, to emulate the behaviour they would have had if they could have been scheduled at the right time.

void PeriodicalActiveObject::registerToScheduler ( ) [virtual, inherited]

Registers this active object to the supposedly already existing scheduler.

Exceptions:

SchedulingException

if the operation failed.

Implements OSDL::Engine::ActiveObject.

Definition at line 152 of file OSDLPeriodicalActiveObject.cc.

References OSDL::Engine::ActiveObject::_registered, OSDL::Engine::Scheduler::GetExistingScheduler(), and OSDL::Engine::Scheduler::registerPeriodicalObject().

Referenced by OSDL::Engine::PeriodicalActiveObject::PeriodicalActiveObject().

void PeriodicalActiveObject::setBirthTick ( Events::SimulationTick currentSimulationTick ) [virtual, inherited]

Sets the birth time, expressed in simulation ticks, of this active object.

Note:: Called by the scheduler, when registering this active object. This object will compute its exact actual begin tick, depending on the sub-slot it has been put in.

Exceptions:

SchedulingException

if the operation failed.

Reimplemented from OSDL::Engine::ActiveObject.

Definition at line 301 of file OSDLPeriodicalActiveObject.cc.

References OSDL::Engine::ActiveObject::_birthTick, OSDL::Engine::PeriodicalActiveObject::_period, and OSDL::Engine::PeriodicalActiveObject::_subslot.

Referenced by OSDL::Engine::Scheduler::registerPeriodicalObject().

virtual Ceylan::Maths::Hertz OSDL::Engine::PeriodicalActiveObject::setFrequency ( Ceylan::Maths::Hertz newFrequency ) [virtual, inherited]

Sets the period of this object so that it gets activated on specified frequency, making this object periodically activated if it was not, or changing its already defined period otherwise.

Parameters:

newFrequency

the desired frequency, expressed in Hertz.

Returns:: The actual chosen frequency, which may differ a bit from specified one since it depends on the simulation tick granularity. Notably, the obtained frequency cannot exceed the specified simulation frequency for the scheduler. The actual frequency is nevertheless chosen as the nearest possible frequency.

Note:: To be able to compute the actual period, expressed in simulation ticks, from the specified frequency, the scheduler that will be later used for this object is needed.

Exceptions:

SchedulingException

if there was no existing scheduler available.

virtual void OSDL::Engine::PeriodicalActiveObject::setPeriod ( Events::Period newPeriod ) [virtual, inherited]

Sets a period for this object, which will be periodically scheduled accordingly.

Parameters:

newPeriod

the new period of activation for this object, expressed in simulation ticks. Must be strictly positive.

Exceptions:

SchedulingException

if the operation failed.

const string PeriodicalModel::toString ( Ceylan::VerbosityLevels level = Ceylan::high ) const [virtual]

Returns an user-friendly description of the state of this object.

Parameters:

level

the requested verbosity level.

Note:: Text output format is determined from overall settings.

See also:: Ceylan::TextDisplayable

Reimplemented from OSDL::Engine::PeriodicalActiveObject.

Definition at line 73 of file OSDLModel.cc.

void PeriodicalActiveObject::unregisterFromScheduler ( ) [virtual, inherited]

Unregisters this active object from the existing scheduler to whom it was supposedly registered.

Exceptions:

SchedulingException

if the operation failed.

Implements OSDL::Engine::ActiveObject.

Definition at line 169 of file OSDLPeriodicalActiveObject.cc.

References OSDL::Engine::ActiveObject::_registered, OSDL::Engine::Scheduler::GetExistingScheduler(), and OSDL::Engine::Scheduler::unregisterPeriodicalObject().

Referenced by OSDL::Engine::PeriodicalActiveObject::~PeriodicalActiveObject().

Member Data Documentation

Events::SimulationTick OSDL::Engine::ActiveObject::_birthTick [protected, inherited]

The date of birth of this object, expressed in simulation time.

Note:: the date of birth corresponds to the first future simulation tick this object is known for the running scheduler (either the scheduler start-up, if this object was registered before), or the simulation tick at which this object was dynamically registered to the scheduler.

Definition at line 373 of file OSDLActiveObject.h.

Referenced by OSDL::Engine::ActiveObject::getBirthTick(), OSDL::Engine::PeriodicalActiveObject::setBirthTick(), and OSDL::Engine::ActiveObject::toString().

Events::Period OSDL::Engine::PeriodicalActiveObject::_period [protected, inherited]

Tells what is the requested scheduling period for this object.

Definition at line 355 of file OSDLPeriodicalActiveObject.h.

Referenced by OSDL::Engine::PeriodicalActiveObject::convertDurationToActivationCount(), OSDL::Engine::PeriodicalActiveObject::getPeriod(), OSDL::Engine::PeriodicalActiveObject::getSubslotNumber(), OSDL::Engine::PeriodicalActiveObject::PeriodicalActiveObject(), OSDL::Engine::PeriodicalActiveObject::setBirthTick(), and OSDL::Engine::PeriodicalActiveObject::toString().