ptolemy.actor
Class AtomicActor

java.lang.Object
  ptolemy.kernel.util.NamedObj
      ptolemy.kernel.InstantiableNamedObj
          ptolemy.kernel.Entity
              ptolemy.kernel.ComponentEntity
                  ptolemy.actor.AtomicActor

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Actor, Executable, FiringsRecordable, Initializable, Changeable, Debuggable, DebugListener, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

Direct Known Subclasses:

NCComponentBase, TypedAtomicActor

public class AtomicActor
extends ComponentEntity
implements Actor, FiringsRecordable

An AtomicActor is an executable entity that cannot itself contain other actors. The Ports of AtomicActors are constrained to be IOPorts. Derived classes may further constrain the ports by overriding the public method newPort() to create a port of the appropriate subclass, and the protected method _addPort() to throw an exception if its argument is a port that is not of the appropriate subclass. In this base class, the actor does nothing in the action methods (prefire, fire, ...).

Since:

Ptolemy II 0.2

Version:

$Id: AtomicActor.java,v 1.127 2008/01/26 02:51:31 cxh Exp $

Author:

Mudit Goel, Edward A. Lee, Lukito Muliadi, Steve Neuendorffer, Contributor: Daniel Crawl

See Also:

CompositeActor, IOPort, Serialized Form

Accepted Rating:

Green (neuendor)

Proposed Rating:

Green (eal)

Nested Class Summary

Nested classes/interfaces inherited from class ptolemy.kernel.Entity

Entity.ContainedObjectsIterator

Field Summary

protected java.util.LinkedList	_actorFiringListeners The list of ActorFiringListeners registered with this object.
protected java.util.List<Initializable>	_initializables List of objects whose (pre)initialize() and wrapup() methods should be slaved to these.
protected boolean	_notifyingActorFiring Flag that is true if there are actor firing listeners.
protected boolean	_stopRequested Indicator that a stop has been requested by a call to stop().

Fields inherited from class ptolemy.kernel.util.NamedObj

_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS

Fields inherited from interface ptolemy.actor.Executable

COMPLETED, NOT_READY, STOP_ITERATING

Constructor Summary

AtomicActor()
Construct an actor in the default workspace with an empty string as its name.

AtomicActor(CompositeEntity container, java.lang.String name)
Create a new actor in the specified container with the specified name.

AtomicActor(Workspace workspace)
Construct an actor in the specified workspace with an empty string as a name.

Method Summary

protected void	_actorFiring(FiringEvent.FiringEventType type, int multiplicity) Send an actor firing event type to all actor firing listeners that have registered with this actor.
protected void	_actorFiring(FiringEvent event) Send an actor firing event to all actor firing listeners that have registered with this actor.
protected void	_addPort(Port port) Override the base class to throw an exception if the added port is not an instance of IOPort.
protected void	_createReceivers() Create receivers for each input port.
void	addActorFiringListener(ActorFiringListener listener) Append a listener to the current set of actor firing listeners.
void	addInitializable(Initializable initializable) Add the specified object to the list of objects whose preinitialize(), intialize(), and wrapup() methods should be invoked upon invocation of the corresponding methods of this object.
java.lang.Object	clone(Workspace workspace) Clone this actor into the specified workspace.
void	connectionsChanged(Port port) Create new receivers if the port is an input port and there is a director.
void	fire() Do nothing.
Director	getDirector() Return the director responsible for the execution of this actor.
Director	getExecutiveDirector() Return the executive director (same as getDirector()).
FunctionDependency	getFunctionDependency() Return a representation of the function dependencies that output ports have on input ports.
Manager	getManager() Return the Manager responsible for execution of this actor, if there is one.
void	initialize() Initialize this actor.
java.util.List	inputPortList() List all the input ports.
boolean	isFireFunctional() Return true.
boolean	isStrict() Return true in this base class.
int	iterate(int count) Invoke a specified number of iterations of the actor.
Port	newPort(java.lang.String name) Create a new IOPort with the specified name.
Receiver	newReceiver() Return a new receiver of a type compatible with the director.
java.util.List	outputPortList() List the output ports.
boolean	postfire() Return true, unless stop() has been called, in which case, return false.
boolean	prefire() Return true.
void	preinitialize() Create receivers.
void	pruneDependencies() Prune the dependency declarations, which by default state that each output port depends on all input ports in a firing.
void	recordFiring(FiringEvent.FiringEventType type) Record a firing event.
void	removeActorFiringListener(ActorFiringListener listener) Unregister an actor firing listener.
void	removeDependency(IOPort input, IOPort output) Remove the dependency that the specified output port has, by default, on the specified input port.
void	removeInitializable(Initializable initializable) Remove the specified object from the list of objects whose preinitialize(), intialize(), and wrapup() methods should be invoked upon invocation of the corresponding methods of this object.
void	setContainer(CompositeEntity container) Override the base class to invalidate the schedule and resolved types of the director.
void	stop() Request that execution of the current iteration stop as soon as possible.
void	stopFire() Request that execution of the current iteration complete.
void	terminate() Terminate execution immediately.
void	wrapup() Do nothing except invoke the wrapup() methods of any objects that have been registered with addInitializable().

Methods inherited from class ptolemy.kernel.ComponentEntity

_adjustDeferrals, _checkContainer, _getContainedObject, _propagateExistence, getContainer, instantiate, isAtomic, isOpaque, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, propagateExistence, setName

Methods inherited from class ptolemy.kernel.Entity

_description, _exportMoMLContents, _removePort, _validateSettables, connectedPortList, connectedPorts, containedObjectsIterator, getAttribute, getPort, getPorts, linkedRelationList, linkedRelations, portList, removeAllPorts, setClassDefinition, uniqueName

Methods inherited from class ptolemy.kernel.InstantiableNamedObj

_setParent, exportMoML, getChildren, getElementName, getParent, getPrototypeList, isClassDefinition, isWithinClassDefinition

Methods inherited from class ptolemy.kernel.util.NamedObj

_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _debug, _debug, _debug, _debug, _debug, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _propagateValue, _removeAttribute, _splitName, _stripNumericSuffix, addChangeListener, addDebugListener, attributeChanged, attributeList, attributeList, attributeTypeChanged, clone, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttributes, getChangeListeners, getClassName, getDerivedLevel, getDerivedList, getDisplayName, getFullName, getModelErrorHandler, getName, getName, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, message, propagateValue, propagateValues, removeChangeListener, removeDebugListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, validateSettables, workspace

Methods inherited from class java.lang.Object

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

Methods inherited from interface ptolemy.kernel.util.Nameable

description, getContainer, getDisplayName, getFullName, getName, getName, setName

Methods inherited from interface ptolemy.kernel.util.Derivable

getDerivedLevel, getDerivedList, propagateValue

Field Detail

_actorFiringListeners

protected java.util.LinkedList _actorFiringListeners

The list of ActorFiringListeners registered with this object. NOTE: Because of the way we synchronize on this object, it should never be reset to null after the first list is created.

_initializables

protected transient java.util.List<Initializable> _initializables

List of objects whose (pre)initialize() and wrapup() methods should be slaved to these.

_notifyingActorFiring

protected boolean _notifyingActorFiring

Flag that is true if there are actor firing listeners.

_stopRequested

protected boolean _stopRequested

Indicator that a stop has been requested by a call to stop().

Constructor Detail

AtomicActor

public AtomicActor()

Construct an actor in the default workspace with an empty string as its name. Increment the version number of the workspace. The object is added to the workspace directory.

AtomicActor

public AtomicActor(Workspace workspace)

Construct an actor in the specified workspace with an empty string as a name. You can then change the name with setName(). If the workspace argument is null, then use the default workspace. The object is added to the workspace directory. Increment the version number of the workspace.

Parameters:

workspace - The workspace that will list this actor.

AtomicActor

public AtomicActor(CompositeEntity container,
                   java.lang.String name)
            throws IllegalActionException,
                   NameDuplicationException

Create a new actor in the specified container with the specified name. The name must be unique within the container or an exception is thrown. The container argument must not be null, or a NullPointerException will be thrown.

Parameters:

container - The container.

name - The name of this actor within the container.

Throws:

IllegalActionException - If the entity cannot be contained by the proposed container (see the setContainer() method).

NameDuplicationException - If the name coincides with an entity already in the container.

Method Detail

addInitializable

public void addInitializable(Initializable initializable)

Add the specified object to the list of objects whose preinitialize(), intialize(), and wrapup() methods should be invoked upon invocation of the corresponding methods of this object.

Specified by:

addInitializable in interface Initializable

Parameters:

initializable - The object whose methods should be invoked.

See Also:

removeInitializable(Initializable), CompositeActor.addPiggyback(Executable)

addActorFiringListener

public void addActorFiringListener(ActorFiringListener listener)

Append a listener to the current set of actor firing listeners. If the listener is already in the set, it will not be added again. Note that this method is basically the same as addDebugListener in the class NamedObj.

Specified by:

addActorFiringListener in interface FiringsRecordable

Parameters:

listener - The listener to which to send actor firing messages.

See Also:

removeActorFiringListener(ActorFiringListener)

clone

public java.lang.Object clone(Workspace workspace)
                       throws java.lang.CloneNotSupportedException

Clone this actor into the specified workspace. The new actor is not added to the directory of that workspace (you must do this yourself if you want it there). The result is a new actor with the same ports as the original, but no connections and no container. A container must be set before much can be done with this actor.

Overrides:

clone in class ComponentEntity

Parameters:

workspace - The workspace for the cloned object.

Returns:

A new ComponentEntity.

Throws:

java.lang.CloneNotSupportedException - If cloned ports cannot have as their container the cloned entity (this should not occur), or if one of the attributes cannot be cloned.

See Also:

NamedObj.exportMoML(Writer, int, String), NamedObj.setDeferringChangeRequests(boolean)

connectionsChanged

public void connectionsChanged(Port port)

Create new receivers if the port is an input port and there is a director.

Overrides:

connectionsChanged in class Entity

Parameters:

port - The port that has connection changes.

fire

public void fire()
          throws IllegalActionException

Do nothing. Derived classes override this method to define their primary run-time action.

Specified by:

fire in interface Executable

Throws:

IllegalActionException - Not thrown in this base class.

getDirector

public Director getDirector()

Return the director responsible for the execution of this actor. In this class, this is always the executive director. Return null if either there is no container or the container has no director.

Specified by:

getDirector in interface Actor

Returns:

The director that invokes this actor.

getExecutiveDirector

public Director getExecutiveDirector()

Return the executive director (same as getDirector()).

Specified by:

getExecutiveDirector in interface Actor

Returns:

The executive director.

getFunctionDependency

public FunctionDependency getFunctionDependency()

Return a representation of the function dependencies that output ports have on input ports.

Specified by:

getFunctionDependency in interface Actor

Returns:

A representation of the function dependencies of the ports of this actor.

See Also:

FunctionDependency

getManager

public Manager getManager()

Return the Manager responsible for execution of this actor, if there is one. Otherwise, return null.

Specified by:

getManager in interface Actor

Returns:

The manager.

initialize

public void initialize()
                throws IllegalActionException

Initialize this actor. Derived classes override this method to perform actions that should occur once at the beginning of an execution, but after type resolution. Derived classes can produce output data and schedule events.

Specified by:

initialize in interface Initializable

Throws:

IllegalActionException - If a derived class throws it.

inputPortList

public java.util.List inputPortList()

List all the input ports. This method is read-synchronized on the workspace.

Specified by:

inputPortList in interface Actor

Returns:

A list of input IOPort objects.

isFireFunctional

public boolean isFireFunctional()

Return true. Most actors are written so that the prefire() and fire() methods do not change the state of the actor. Hence, for convenience, this base class by default returns true. An actor that does change state in prefire() or fire() must override this method to return false.

Specified by:

isFireFunctional in interface Executable

Returns:

True.

isStrict

public boolean isStrict()

Return true in this base class. By default, actors do not check their inputs to see whether they are known. They assume they are known. A derived class that can tolerate unknown inputs should override this method to return false.

Specified by:

isStrict in interface Executable

Returns:

True always in this base class.

iterate

public int iterate(int count)
            throws IllegalActionException

Invoke a specified number of iterations of the actor. An iteration is equivalent to invoking prefire(), fire(), and postfire(), in that order. In an iteration, if prefire() returns true, then fire() will be called once, followed by postfire(). Otherwise, if prefire() returns false, fire() and postfire() are not invoked, and this method returns NOT_READY. If postfire() returns false, then no more iterations are invoked, and this method returns STOP_ITERATING. Otherwise, it returns COMPLETED. If stop() is called while this is executing, then cease executing and return STOP_ITERATING.

This base class method actually invokes prefire(), fire(), and postfire(), as described above, but a derived class may override the method to execute more efficient code.

Specified by:

iterate in interface Executable

Parameters:

count - The number of iterations to perform.

Returns:

NOT_READY, STOP_ITERATING, or COMPLETED.

Throws:

IllegalActionException - If iterating is not permitted, or if prefire(), fire(), or postfire() throw it.

newPort

public Port newPort(java.lang.String name)
             throws NameDuplicationException

Create a new IOPort with the specified name. The container of the port is set to this actor. This method is write-synchronized on the workspace. Normally this method is not called directly by actor code. Instead, a change request should be queued with the director.

Overrides:

newPort in class ComponentEntity

Parameters:

name - The name for the new port.

Returns:

The new port.

Throws:

NameDuplicationException - If this actor already has a port with the specified name.

See Also:

Workspace.getWriteAccess()

newReceiver

public Receiver newReceiver()
                     throws IllegalActionException

Return a new receiver of a type compatible with the director. Derived classes may further specialize this to return a receiver specialized to the particular actor.

Specified by:

newReceiver in interface Actor

Returns:

A new object implementing the Receiver interface.

Throws:

IllegalActionException - If there is no director.

outputPortList

public java.util.List outputPortList()

List the output ports. This method is read-synchronized on the workspace.

Specified by:

outputPortList in interface Actor

Returns:

A list of output IOPort objects.

postfire

public boolean postfire()
                 throws IllegalActionException

Return true, unless stop() has been called, in which case, return false. Derived classes override this method to define operations to be performed at the end of every iteration of its execution, after one invocation of the prefire() method and any number of invocations of the fire() method. This method typically wraps up an iteration, which may involve updating local state. In derived classes, this method returns false to indicate that this actor should not be fired again.

Specified by:

postfire in interface Executable

Returns:

True if execution can continue into the next iteration.

Throws:

IllegalActionException - Not thrown in this base class.

prefire

public boolean prefire()
                throws IllegalActionException

Return true. Derived classes override this method to define operations to be performed at the beginning of every iteration of its execution, prior the invocation of the fire() method. Derived classes may also use it to check preconditions for an iteration, if there are any.

Specified by:

prefire in interface Executable

Returns:

True if this actor is ready for firing, false otherwise.

Throws:

IllegalActionException - Not thrown in this base class.

preinitialize

public void preinitialize()
                   throws IllegalActionException

Create receivers. Derived classes can override this method to perform additional initialization functions, but they should call this base class methods or create the receivers themselves. This method gets executed exactly once prior to any other action methods. It cannot produce output data since type resolution is typically not yet done. It also gets invoked prior to any static scheduling that might occur in the domain, so it can change scheduling information.

Specified by:

preinitialize in interface Initializable

Throws:

IllegalActionException - Not thrown in this base class.

pruneDependencies

public void pruneDependencies()

Prune the dependency declarations, which by default state that each output port depends on all input ports in a firing. This base class does no pruning, but subclasses that have output ports that do not depend on input ports should override this method to prune the dependencies. To declare that an output port does not depend on an input port, subclasses should call removeDependency(input, output).

See Also:

TimedDelay, removeDependency(IOPort, IOPort), FunctionDependencyOfAtomicActor

recordFiring

public void recordFiring(FiringEvent.FiringEventType type)

Record a firing event.

Specified by:

recordFiring in interface FiringsRecordable

Parameters:

type - The firing event to be recorded.

removeActorFiringListener

public void removeActorFiringListener(ActorFiringListener listener)

Unregister an actor firing listener. If the specified listener has not been previously registered, then do nothing. Note that this method is basically the same as removeDebugListener in the class NamedObj.

Specified by:

removeActorFiringListener in interface FiringsRecordable

Parameters:

listener - The listener to remove from the list of listeners to which actor firing messages are sent.

See Also:

addActorFiringListener(ActorFiringListener)

removeDependency

public void removeDependency(IOPort input,
                             IOPort output)

Remove the dependency that the specified output port has, by default, on the specified input port. By default, each output port is assumed to have a dependency on all input ports. Subclasses should call this method inside their override of the pruneDependencies() method if a particular output port does not depend on data from a particular input port in a firing. There should be one such call for each input, output pair that does not have a dependency.

Parameters:

input - The input port.

output - The output port that does not depend on the input port.

See Also:

FunctionDependencyOfAtomicActor

removeInitializable

public void removeInitializable(Initializable initializable)

Remove the specified object from the list of objects whose preinitialize(), intialize(), and wrapup() methods should be invoked upon invocation of the corresponding methods of this object. If the specified object is not on the list, do nothing.

Specified by:

removeInitializable in interface Initializable

Parameters:

initializable - The object whose methods should no longer be invoked.

See Also:

addInitializable(Initializable), CompositeActor.removePiggyback(Executable)

setContainer

public void setContainer(CompositeEntity container)
                  throws IllegalActionException,
                         NameDuplicationException

Override the base class to invalidate the schedule and resolved types of the director.

Overrides:

setContainer in class ComponentEntity

Parameters:

container - The proposed container.

Throws:

IllegalActionException - If the action would result in a recursive containment structure, or if this entity and container are not in the same workspace.

NameDuplicationException - If the container already has an entity with the name of this entity.

See Also:

ComponentEntity.getContainer()

stop

public void stop()

Request that execution of the current iteration stop as soon as possible. In this base class, we set a flag indicating that this request has been made (the protected variable _stopRequested). Most atomic actors have bounded fire() methods, so they can simply ignore this. Atomic actors with unbounded fire() methods should react by saving their state and returning from the fire() method at the next convenient point.

Specified by:

stop in interface Executable

stopFire

public void stopFire()

Request that execution of the current iteration complete. Most atomic actors have bounded fire() methods, so they can simply ignore this. Atomic actors with unbounded fire() methods should override this method to save their state and return from the fire() method at the next convenient point. In this base class, do nothing.

Specified by:

stopFire in interface Executable

terminate

public void terminate()

Terminate execution immediately. In this base class, call stop(). Derived classes may wish to do something more aggressive, such as terminating any threads they have started.

Specified by:

terminate in interface Executable

wrapup

public void wrapup()
            throws IllegalActionException

Do nothing except invoke the wrapup() methods of any objects that have been registered with addInitializable(). Derived classes override this method to define operations to be performed exactly once at the end of a complete execution of an application. It typically closes files, displays final results, etc.

Specified by:

wrapup in interface Initializable

Throws:

IllegalActionException - Not thrown in this base class.

_actorFiring

protected final void _actorFiring(FiringEvent event)

Send an actor firing event to all actor firing listeners that have registered with this actor.

Parameters:

event - The event.

_actorFiring

protected final void _actorFiring(FiringEvent.FiringEventType type,
                                  int multiplicity)

Send an actor firing event type to all actor firing listeners that have registered with this actor.

Parameters:

type - The type.

multiplicity - The multiplicity of the firing, that is, the number of times the firing will occur or has occurred.

_addPort

protected void _addPort(Port port)
                 throws IllegalActionException,
                        NameDuplicationException

Override the base class to throw an exception if the added port is not an instance of IOPort. This method should not be used directly. Call the setContainer() method of the port instead. This method does not set the container of the port to point to this entity. It assumes that the port is in the same workspace as this entity, but does not check. The caller should check. Derived classes may override this method to further constrain to a subclass of IOPort. This method is not synchronized on the workspace, so the caller should be.

Overrides:

_addPort in class ComponentEntity

Parameters:

port - The port to add to this entity.

Throws:

IllegalActionException - If the port class is not acceptable to this entity, or the port has no name.

NameDuplicationException - If the port name coincides with a name already in the entity.

_createReceivers

protected void _createReceivers()
                         throws IllegalActionException

Create receivers for each input port.

Throws:

IllegalActionException - If any port throws it.