desmoj.core.simulator

Class EventAbstract

java.lang.Object

desmoj.core.simulator.NamedObject

desmoj.core.simulator.ModelComponent

desmoj.core.simulator.Schedulable

desmoj.core.simulator.EventAbstract

Direct Known Subclasses:

Event, EventOf2Entities, EventOf3Entities, ExternalEvent

public abstract class EventAbstract
extends Schedulable

Provides the abstract super class for user defined events to change an entity's internal state. The state of a discrete model is changed by events that occur at distinct points of simulation time.

an event with up to three entities, changing its state according to the entity's reaction to the specific Event in the system under inspection. So each type of Event acting on one certain type of Entity requires a new subclass to be derived from this class. Since events are associated to a single entity, the method executing the changes of state of a specific Entity gets that entity passed as a parameter. The scheduler takes care that this is done at the specified point of simulation time.

For type safety it is recommended to generically assign the entity type an Event operates on by using the generic type Event<EntityOperatingOn> where EntityOperatingOn is derived from Entity.

events should be used one time only. They are created to be scheduled together with a specific Entity, change that entity's state at the scheduled point of simulation time and are destroyed by Java's garbage collector after use. They could be reused but at a certain risk of inconsistent states. Since each object of a class that is derived from the class Schedulable has its unique identification number added as a suffix to its name, reusing Event objects would make one event responsible for several distinct changes in a model at different simulation times. This comes with the danger of of confusing the model's trace and making it more difficult to debug a faulty model implementation. Each type of Event needed for a model requires a new subclass of Event to be derived by the user.

Embed the changes of state for the specific Entity associated with this event by overriding the abstract method eventRoutine(Entity e). Events that do not manipulate a single entity but act on the model's state on a more general matter are defined by external events, a subclass of this class.

Version:

DESMO-J, Ver. 2.5.1c copyright (c) 2015

Author:

Tim Lechler Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

See Also:

Entity, ExternalEvent, TimeInstant, TimeSpan

Constructor Summary

Constructors

Constructor and Description
EventAbstract(Model owner, java.lang.String name, boolean showInTrace) Creates a new event of the given model, with the given name and trace option.

Method Summary

Modifier and Type	Method and Description
long	getNumberOfEntities() Returns the realTime deadline for this event (in nanoseconds).
long	getRealTimeConstraint() Returns the realTime deadline for this event (in nanoseconds).
int	getSchedulingPriority() Returns the event's scheduling priority.
boolean	isExternal() Tests if this event actually is an external event which is not used for modelling but to control the experiment to act at certain points of simulation time.
void	setRealTimeConstraint(long realTimeConstraint) Sets the realTime deadline for this event (in nanoseconds).
void	setSchedulingPriority(int newPriority) Sets the entity's scheduling priority to a given integer value.

Methods inherited from class desmoj.core.simulator.Schedulable

assignReporter, cancel, getCorrespondingReportable, isCurrent, isScheduled, rename, reSchedule, reSchedule, reSchedulePreempt, scheduledNext, setCorrespondingReportable

Methods inherited from class desmoj.core.simulator.ModelComponent

current, currentEntity, currentEntityAll, currentEvent, currentModel, currentSimProcess, debugIsOn, debugOff, debugOn, getModel, isExperimentCompatible, isModelCompatible, presentTime, sendDebugNote, sendMessage, sendTraceNote, sendWarning, skipTraceNote, skipTraceNote, traceIsOn, traceOff, traceOn

Methods inherited from class desmoj.core.simulator.NamedObject

getName, getQuotedName, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

EventAbstract

public EventAbstract(Model owner,
                     java.lang.String name,
                     boolean showInTrace)

Creates a new event of the given model, with the given name and trace option.

Parameters:

name - java.lang.String : The name of this event

owner - Model : The model this event is associated to

showInTrace - boolean : Flag for showing event in trace-files. Set it to true if event should show up in trace. Set it to false if event should not be shown in trace.

Method Detail

isExternal

public boolean isExternal()

Tests if this event actually is an external event which is not used for modelling but to control the experiment to act at certain points of simulation time. External events must not be connected to an entity.

Returns:

boolean : Is true if this is an instance of class ExternalEvent,false otherwise

getRealTimeConstraint

public long getRealTimeConstraint()

Returns the realTime deadline for this event (in nanoseconds). In case of a real-time execution (i. e. the execution speed rate is set to a positive value) the Scheduler will produce a warning message if a deadline is missed.

Returns:

the realTimeConstraint in nanoseconds

getNumberOfEntities

public long getNumberOfEntities()

Returns the realTime deadline for this event (in nanoseconds). In case of a real-time execution (i. e. the execution speed rate is set to a positive value) the Scheduler will produce a warning message if a deadline is missed.

Returns:

the realTimeConstraint in nanoseconds

setRealTimeConstraint

public void setRealTimeConstraint(long realTimeConstraint)

Sets the realTime deadline for this event (in nanoseconds). In case of a real-time execution (i. e. the execution speed rate is set to a positive value) the Scheduler will produce a warning message if a deadline is missed.

Parameters:

realTimeConstraint - the realTimeConstraint in nanoseconds to set

getSchedulingPriority

public int getSchedulingPriority()

Returns the event's scheduling priority. The scheduling priority is used to determine which event to execute first if two or more events are scheduled at the same instant. The default priority is zero. Higher priorities are positive, lower priorities negative.

Returns:

int : The events's priority

setSchedulingPriority

public void setSchedulingPriority(int newPriority)

Sets the entity's scheduling priority to a given integer value. The default priority (unless assigned otherwise) is zero. Negative priorities are lower, positive priorities are higher. All values should be inside the range defined by Java's integral integer data type [-2147483648, +2147483647]. An event's scheduling priority it used to determine which event is executed first if scheduled for the same time instant. Should the priority be the same, event execution depends on the EventList in use, e.g. scheduled first is executed first (EventTreeList) or random (RandomizingEventTreeList).

Parameters:

newPriority - int : The new scheduling priority value