Class Scheduler<T extends SimuTimer<?>>

java.lang.Object
madkit.kernel.Agent
madkit.simulation.SimuAgent
madkit.kernel.Scheduler<T>
Type Parameters:
T - the type of the simulation time. It should be a subclass of either a DateBasedTimer or a TickBasedTimer. Two different temporal schemes could used:
  • tick-based: The time is represented as a BigDecimal which is incremented at will. BigDecimal is used to avoid rounding errors that may happen when working with double values. This is the preferred choice if the simulation is based on simple loop following a discrete time approach.
  • date-based: The time is represented using LocalDateTime. This is far more convenient when the model refers to a real-world case for which representing usual temporal units such as hours or weeks is required (the default used unit is ChronoUnit.SECONDS). This mode also allow to handle agents that evolve considering different time scales or during specific period of the day.
Direct Known Subclasses:
DateBasedDiscreteEventScheduler, TickBasedScheduler
public abstract class Scheduler<T extends SimuTimer<?>> extends SimuAgent
 Scheduler is the core agent for defining multi-agent based simulations in MaDKit.
 
 
 This class defines a generic threaded agent which is in charge of activating the
 simulated agents using Activator. Activator are tool objects which are
 able to trigger any available method belonging to agents having a role within a group.
 
 
 The interest of this approach is twofold:
 
    
 
  • Firstly it allows the manipulation of agents regardless of their concrete Java
 classes.
 
  • Secondly it allows to define complex scheduling policies by defining different
 activators.
 

 
 
 So a scheduler holds a collection of activators that target specific groups and roles
 and thus allow to define very complex scheduling policies if required. A default
 behavior is implemented and corresponds to the triggering of the activators according
 to the order in which they have been added to the scheduler engine using
 addActivator(Activator).
 
 
 The default state of a scheduler is Scheduler.SimulationState.PAUSED.
 
 
 The default delay between two simulation steps is 0 milliseconds (max speed).
 
 
 Default GUI components are defined for this agent and they could be easily integrated
 in any GUI.
See Also:

  • Constructor Details

    • Scheduler

      protected Scheduler()
      Default constructor. It automatically initializes the simulation time according to the type of the simulation time.

  • Method Details

    • onActivation

      protected void onActivation()
      On activation, by default the scheduler requests the role SimuOrganization.SCHEDULER_ROLE in the group SimuOrganization.ENGINE_GROUP.
      Overrides:
      onActivation in class Agent

    • onLive

      protected void onLive()
      The main loop of the scheduler agent. It is automatically called by the MaDKit kernel once the agent is activated. Firstly, the scheduler waits for the first message to start the simulation. Then, it enters an infinite loop where it waits for messages, checks the simulation state, and processes the simulation step accordingly. The loop is interrupted when the simulation reaches the end time or when a SHUTDOWN message is received.
      Overrides:
      onLive in class Agent

    • onSimulationStart

      public void onSimulationStart()
      Called when the simulation starts, or when the user clicks on the onsimulationrestart button. By default, it resets the simulation time and calls the onSimulationStart() method of the environment agent
      Overrides:
      onSimulationStart in class SimuAgent

    • onEnd

      protected void onEnd()
      Called when the simulation ends.
      Overrides:
      onEnd in class Agent

    • doSimulationStep

      protected abstract void doSimulationStep()
      Defines a simulation step. This method should be overridden to define a customized scheduling policy.

    • getPause

      public int getPause()
      Returns the delay between two simulation steps.
      Returns:
      the pause between two steps

    • setPause

      public void setPause(int delay)
      Sets the delay between two simulation steps.
      Parameters:
      delay - the pause between two steps

    • getPauseSlider

      public Slider getPauseSlider()
      Gets a Slider that can manipulate the pause between two simulation steps.
      Returns:
      a Slider to change the pause between two simulation steps

    • getToolBar

      public ToolBar getToolBar()
      Returns a ToolBar made of scheduling actions, a pause slider and a label displaying the current simulation time.
      Returns:
      a ToolBar made of common scheduling actions.

    • getShedulerActions

      public ActionGroup getShedulerActions()
      Returns the actions group that can be used to control the simulation.
      Returns:
      the shedulingActions as an ActionGroup

    • getActions

      public List<Action> getActions()
      Returns the actions that can be used to control the simulation.
      Returns:
      the actions as a List

    • getTimeLabel

      public Label getTimeLabel()
      Returns a Label displaying the time of the simulation.
      Returns:
      the current simulation state

    • setSimulationTime

      protected void setSimulationTime(T simulationTime)
      Sets the simulation time of the simulation.
      Parameters:
      simulationTime - the simulationTime to set

    • getSimuTimer

      public T getSimuTimer()
      Returns the SimuTimer of the scheduler.
      Overrides:
      getSimuTimer in class SimuAgent
      Returns:
      the SimuTimer of the scheduler

    • getActivators

      public List<Activator> getActivators()
      Gets the list of activators that are currently added to the simulation engine by this scheduler.
      Returns:
      a list of activators.

    • addViewersActivator

      public MethodActivator addViewersActivator()
      Adds the default activator for viewers and returns it. The default activator for viewers is an activator that triggers the method Viewer.display() of agents playing the role SimuOrganization.VIEWER_ROLE in the group SimuOrganization.ENGINE_GROUP
      Returns:
      an activator that triggers viewers display method

    • addEnvironmentActivator

      public MethodActivator addEnvironmentActivator()
      Adds the default activator for environment and returns it. The default activator for environment is an activator that triggers the method update of agents playing the role SimuOrganization.ENVIRONMENT_ROLE in the group SimuOrganization.ENGINE_GROUP
      Returns:
      an activator that triggers the environment update method

    • addActivator

      public boolean addActivator(Activator activator)
      Adds an activator to the simulation engine. This has to be done before the simulation starts. It is possible to add several activators to the simulation engine. Once added, the activator can be triggered by the scheduler agent using the Activator.execute(Object...) method.
      Parameters:
      activator - an activator to add to the simulation engine.
      Returns:
      true if the activator has been added, false if it was already added

    • removeActivator

      public void removeActivator(Activator activator)
      Removes an activator from the simulation engine.
      Parameters:
      activator - an activator.

    • logCurrrentTime

      public void logCurrrentTime()
      Logs the current simulation time value. logs are displayed only if Agent.getLogger() is set above Level.FINE.

    • executeAndLog

      protected void executeAndLog(Activator activator, Object... args)
      Triggers the execute method of this activator and logs it using the Level.FINER logging level.
      Parameters:
      activator - the activator to trigger
      args - the args that will be passed to the targeted method

    • removeAllActivators

      public void removeAllActivators()
      Remove all the activators which have been previously added.