jeops.conflict
Class LRUConflictSet

java.lang.Object
  |
  +--jeops.conflict.AbstractConflictSet
        |
        +--jeops.conflict.LRUConflictSet

public class LRUConflictSet

extends AbstractConflictSet

A conflict set whose conflict resolution policy is one that the least recently fired rules have priority over the remaining ones.

Version:

0.01 14 Apr 2000

Author:

Carlos Figueira Filho (csff@cin.ufpe.br)

Field Summary

private java.util.Vector	fireableRules The vector where the fireable rules are stored.
private java.util.Vector	history The history of rule firings.
private int	size The number of elements in this conflict set.

Fields inherited from class jeops.conflict.AbstractConflictSet

debug, listeners

Constructor Summary

LRUConflictSet()
Class constructor.

Method Summary

private void	ensureFireableRulesCapacity(int size) Auxiliar method that ensures that the fireable rules vector has as many elements as the given integer.
void	flush() Removes all rules from this conflict set, as well as cleaning any history that might have been stored.
void	insertElement(ConflictSetElement element) Inserts a rule instantiation.
boolean	isEmpty() Checks whether this set has any elements.
ConflictSetElement	nextElement() Returns the next rule to be fired.
void	removeElementsWith(java.lang.Object obj) Remove all elements from this set that uses the given object in its instantiations.

Methods inherited from class jeops.conflict.AbstractConflictSet

addInternalConflictSetListener, elementAdded, elementRemoved, fireInternalElementAddedEvent, fireInternalElementRemovedEvent, removeElementsWith_1D, removeElementsWith_2D, removeInternalConflictSetListener

Methods inherited from class java.lang.Object

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

Field Detail

fireableRules

private java.util.Vector fireableRules

The vector where the fireable rules are stored. It's actually a vector of vectors, to simulate a bidimensional matrix: the lines represent the rules and the columns will have their instantiations.

history

private java.util.Vector history

The history of rule firings. If one number (of rule) is after another one, it means that that rule was fired most recently.

size

private int size

The number of elements in this conflict set.

Constructor Detail

LRUConflictSet

public LRUConflictSet()

Class constructor.

Method Detail

ensureFireableRulesCapacity

private void ensureFireableRulesCapacity(int size)

Auxiliar method that ensures that the fireable rules vector has as many elements as the given integer.

Parameters:

size - the size the vector must have.

flush

public void flush()

Removes all rules from this conflict set, as well as cleaning any history that might have been stored.

insertElement

public void insertElement(ConflictSetElement element)

Inserts a rule instantiation.

Parameters:

element - a conflict set element that holds the rule index as well as the objects bound to the rule declarations.

isEmpty

public boolean isEmpty()

Checks whether this set has any elements.

Returns:

false if there is at least one fireable rule in this set; true otherwise.

nextElement

public ConflictSetElement nextElement()
                               throws NoMoreElementsException

Returns the next rule to be fired.

Returns:

a conflict set element among those that have been inserted in this object, according to the policy defined in this conflict set.

Throws:

NoMoreElementsException - if there aren't any more elements in this conflict set.

removeElementsWith

public void removeElementsWith(java.lang.Object obj)

Remove all elements from this set that uses the given object in its instantiations.

Parameters:

obj - the given object