br.pucrio.inf.les.bdijade.core
Class Intention

java.lang.Object
  br.pucrio.inf.les.bdijade.core.Intention

public class Intention
extends java.lang.Object

This class represents the intention abstraction from the BDI model. It represents a goal that the agent is committed to achieve. It has the associated goal and tries to execute plans to achieve it. It keeps a list of the executed plans, and after using all plans unsuccessfully, the goal is considered unachievable. When a plan fails, the BDI-interpreter cycle may invoke the tryToAchive() method again, so the intention tries another plan. During its execution, the intention can be set to no longer desired.

Author:

ingrid

Field Summary

private PlanInstance	currentPlan
private java.util.Set<Plan>	executedPlans
private Goal	goal
private java.util.List<GoalListener>	goalListeners
private org.apache.commons.logging.Log	log
private BDIAgent	myAgent
private boolean	noLongerDesired
private Capability	owner
private boolean	unachievable
private boolean	waiting

Constructor Summary

Intention(BDIAgent bdiAgent, Goal goal)
Creates a new intention.

Intention(Goal goal, BDIAgent bdiAgent, Capability owner)
Creates a new intention.

Method Summary

void	addGoalListener(GoalListener goalListener) Adds a listener to be notified when the given has achieve its end state.
protected void	dispatchPlan() Dispatches a new plan to try to achieve the intention goal.
void	doWait() Sets this intention to the GoalStatus.WAITING status.
private void	fireGoalEvent(GoalEvent goalEvent) Notify all listeners, if any, about a goal event.
void	fireGoalFinishedEvent() Fires a goal event when a goal has achieved its end state.
private java.util.Set<Plan>	getCanAchievePlans() Returns all plans from all capabilities that can achieve the goal.
Goal	getGoal()
java.util.List<GoalListener>	getGoalListeners()
BDIAgent	getMyAgent()
GoalStatus	getStatus() Returns the current goal status that this capability is committed to achieve.
void	noLongerDesire() Sets this intention as no longer desired.
void	removeGoalListener(GoalListener goalListener) Removes a goal listener to not be notified about the goal achievement anymore.
void	tryToAchive() Makes this intention starts to try to achieve the goal.

Methods inherited from class java.lang.Object

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

Field Detail

currentPlan

private PlanInstance currentPlan

executedPlans

private final java.util.Set<Plan> executedPlans

goal

private final Goal goal

goalListeners

private final java.util.List<GoalListener> goalListeners

log

private final org.apache.commons.logging.Log log

myAgent

private final BDIAgent myAgent

noLongerDesired

private boolean noLongerDesired

owner

private Capability owner

unachievable

private boolean unachievable

waiting

private boolean waiting

Constructor Detail

Intention

public Intention(BDIAgent bdiAgent,
                 Goal goal)

Creates a new intention. It is associated with an agent and the goal that it is committed to achieve.

Parameters:

goal - the goal to be achieved.

bdiAgent - the bdiAgent associated with this intention.

Intention

public Intention(Goal goal,
                 BDIAgent bdiAgent,
                 Capability owner)

Creates a new intention. It is associated with an agent and the goal that it is committed to achieve. It also receives a Capability as parameter indicating the owner of the goal (dispatched the goal).

Parameters:

goal - the goal to be achieved.

bdiAgent - the bdiAgent associated with this intention.

owner - the Capability that is owner of the goal.

Method Detail

addGoalListener

public void addGoalListener(GoalListener goalListener)

Adds a listener to be notified when the given has achieve its end state.

Parameters:

goalListener - the listener to be notified.

dispatchPlan

protected void dispatchPlan()

Dispatches a new plan to try to achieve the intention goal. It looks for plans that can achieve the goal that were not already tried and then starts the plan. If all possible plans were already executed, the intention is set to unachievable.

doWait

public void doWait()

Sets this intention to the GoalStatus.WAITING status. It may come from the GoalStatus.PLAN_FAILED or GoalStatus.TRYING_TO_ACHIEVE states.

fireGoalEvent

private void fireGoalEvent(GoalEvent goalEvent)

Notify all listeners, if any, about a goal event.

Parameters:

goalEvent -

fireGoalFinishedEvent

public void fireGoalFinishedEvent()

Fires a goal event when a goal has achieved its end state.

See Also:

GoalStatus

getCanAchievePlans

private java.util.Set<Plan> getCanAchievePlans()

Returns all plans from all capabilities that can achieve the goal.

Returns:

the set of plans that can achieve the goal.

getGoal

public Goal getGoal()

Returns:

the goal

getGoalListeners

public java.util.List<GoalListener> getGoalListeners()

Returns:

the goalListeners

getMyAgent

public BDIAgent getMyAgent()

Returns:

the myAgent

getStatus

public GoalStatus getStatus()

Returns the current goal status that this capability is committed to achieve.

Returns:

the current goal status.

See Also:

GoalStatus

noLongerDesire

public void noLongerDesire()

Sets this intention as no longer desired. It stops the current plan execution. It changes the goal status from GoalStatus.WAITING, GoalStatus.PLAN_FAILED or GoalStatus.TRYING_TO_ACHIEVE to GoalStatus.NO_LONGER_DESIRED.

removeGoalListener

public void removeGoalListener(GoalListener goalListener)

Removes a goal listener to not be notified about the goal achievement anymore.

Parameters:

goalListener - the goal listener to be removed.

tryToAchive

public void tryToAchive()

Makes this intention starts to try to achieve the goal. It changes the goal status from GoalStatus.WAITING or GoalStatus.PLAN_FAILED to GoalStatus.TRYING_TO_ACHIEVE.