bdi4jade.belief

Class DerivedBelief<K,V>

java.lang.Object

bdi4jade.core.MetadataElementImpl

bdi4jade.belief.AbstractBelief<K,V>

bdi4jade.belief.DerivedBelief<K,V>

All Implemented Interfaces:

Belief<K,V>, MetadataElement, jade.content.Concept, jade.content.ContentElement, jade.content.Term, java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

DerivedPredicate

public abstract class DerivedBelief<K,V>
extends AbstractBelief<K,V>

This class represents a belief whose value is derived from other beliefs of a belief base. As a belief may be part of many belief bases, a main belief base is associated with this belief. The evaluation of the value of this belief is performed considering the belief of the main belief base.

Author:

Ingrid Nunes

See Also:

Serialized Form

Field Summary

Fields inherited from class bdi4jade.core.MetadataElementImpl

metadata

Constructor Summary

Constructors

Constructor and Description
DerivedBelief() The default constructor.
DerivedBelief(K name) Creates a new derived belief.

Method Summary

Modifier and Type	Method and Description
void	addBeliefBase(BeliefBase beliefBase) Adds a belief base with which this belief is associated.
protected abstract V	evaluate() Evaluates the value of this belief, which is derived from beliefs of the main belief base associated with this belief.
BeliefBase	getMainBeliefBase() Returns the main belief base of this belief.
V	getValue() Returns the value of this belief.
void	removeBeliefBase(BeliefBase beliefBase) Removes a belief base associated with this belief.
void	setMainBeliefBase(BeliefBase mainBeliefBase) Sets the main belief base of this belief.
protected void	updateValue(V value) This method throws a NullPointerException, as this operation is invalid for this belief.

Methods inherited from class bdi4jade.belief.AbstractBelief

clone, equals, getBeliefBases, getName, hashCode, notifyBeliefBases, setName, setValue, toString

Methods inherited from class bdi4jade.core.MetadataElementImpl

getMetadata, getMetadata, hasMetadata, putMetadata, removeMetadata

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface bdi4jade.core.MetadataElement

getMetadata, getMetadata, hasMetadata, putMetadata, removeMetadata

Constructor Detail

DerivedBelief

public DerivedBelief()

The default constructor. It should be only used if persistence frameworks are used.

DerivedBelief

public DerivedBelief(K name)

Creates a new derived belief. The value of this belief cannot be set as it is derived from other values of a belief base.

Parameters:

name - the belief name.

Method Detail

addBeliefBase

public void addBeliefBase(BeliefBase beliefBase)

Adds a belief base with which this belief is associated. If the main belief base of this belief is null, it sets the given belief base as the main belief base of this belief.

Specified by:

addBeliefBase in interface Belief<K,V>

Overrides:

addBeliefBase in class AbstractBelief<K,V>

Parameters:

beliefBase - the belief base to be added.

See Also:

AbstractBelief.addBeliefBase(bdi4jade.belief.BeliefBase)

evaluate

protected abstract V evaluate()

Evaluates the value of this belief, which is derived from beliefs of the main belief base associated with this belief.

Returns:

the value of this belief.

getMainBeliefBase

public BeliefBase getMainBeliefBase()

Returns the main belief base of this belief.

Returns:

the main belief base.

getValue

public V getValue()

Returns the value of this belief. If the main belief base is null, it returns null. Otherwise, the method evaluate() is invoked.

Returns:

the value of this belief.

See Also:

Belief.getValue()

removeBeliefBase

public void removeBeliefBase(BeliefBase beliefBase)

Removes a belief base associated with this belief. If the belief base was the main belief base of this belief, this method sets a random belief base from the belief bases associated with this belief as the main belief base. If the removed belief base was the last belief base associated with this belief, the main belief base is set to null.

Specified by:

removeBeliefBase in interface Belief<K,V>

Overrides:

removeBeliefBase in class AbstractBelief<K,V>

Parameters:

beliefBase - the belief base to be removed.

See Also:

AbstractBelief.removeBeliefBase(bdi4jade.belief.BeliefBase)

setMainBeliefBase

public void setMainBeliefBase(BeliefBase mainBeliefBase)

Sets the main belief base of this belief. This method does not verify if the main belief base is one of the belief bases associated with this belief.

Parameters:

mainBeliefBase - the main belief base to set.

updateValue

protected void updateValue(V value)

This method throws a NullPointerException, as this operation is invalid for this belief. The value of this belief cannot be set as it is derived from other beliefs.

Specified by:

updateValue in class AbstractBelief<K,V>

Parameters:

value - the value to set.