org.jacop.constraints.netflow

Class Network

java.lang.Object

org.jacop.constraints.netflow.simplex.NetworkSimplex

org.jacop.constraints.netflow.Network

All Implemented Interfaces:

MutableNetwork

Direct Known Subclasses:

Pruning

public class Network
extends NetworkSimplex
implements MutableNetwork

This class extends the minimum-cost flow network by providing operations and data structures for removal and modification of arcs.

Version:

4.9

Author:

Robin Steiger and Radoslaw Szymanek

Field Summary

Fields

Modifier and Type	Field and Description
long	costOffset Cost due to deleted arcs
List<Arc>	deletedArcs List of deleted arcs (contains no duplicates)
TimeStamp<Integer>	deletedSize Number of deleted arcs at each level
LinkedHashSet<ArcCompanion>	lastModifiedArcs Set of arcs modified at current level
List<ArcCompanion>	modifiedArcs List of modified arcs (may contain duplicates)
TimeStamp<Integer>	modifiedSize Number of modified arcs at each level
Store	store The store

Fields inherited from class org.jacop.constraints.netflow.simplex.NetworkSimplex

allArcs, blocking, DEBUG, DEBUG_ALL, DELETED_ARC, infeasibleNodes, LARGE_COST, lower, nodes, numArcs, pivotRule, root, TREE_ARC

Constructor Summary

Constructors

Constructor and Description
Network(List<org.jacop.constraints.netflow.simplex.Node> nodes, List<Arc> arcs)

Method Summary

Modifier and Type	Method and Description
void	backtrack()
void	changeCostOffset(long delta) Changes the cost offset by some value.
long	cost(long cutoff)
int	getStoreLevel() Retrieves the current store level for domain pruning.
void	increaseLevel()
void	initialize(Store store)
void	modified(ArcCompanion companion) Tells the network that an arc has been modified.
boolean	needsUpdate(int maxCost)
void	remove(Arc arc) Removes an arc from the network.

Methods inherited from class org.jacop.constraints.netflow.simplex.NetworkSimplex

addArc, addArcWithFlow, augmentFlow, dualPivot, networkSimplex, parametricStep, primalStep, print, removeArc, treeSwap, updateTree

Methods inherited from class java.lang.Object

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

Field Detail

deletedArcs

public final List<Arc> deletedArcs

List of deleted arcs (contains no duplicates)

deletedSize

public TimeStamp<Integer> deletedSize

Number of deleted arcs at each level

costOffset

public long costOffset

Cost due to deleted arcs

modifiedArcs

public final List<ArcCompanion> modifiedArcs

List of modified arcs (may contain duplicates)

modifiedSize

public TimeStamp<Integer> modifiedSize

Number of modified arcs at each level

lastModifiedArcs

public final LinkedHashSet<ArcCompanion> lastModifiedArcs

Set of arcs modified at current level

store

public Store store

The store

Constructor Detail

Network

public Network(List<org.jacop.constraints.netflow.simplex.Node> nodes,
               List<Arc> arcs)

Method Detail

initialize

public void initialize(Store store)

remove

public void remove(Arc arc)

Description copied from interface: MutableNetwork

Removes an arc from the network. The arc must be at its lower or upper bound before it can be removed.

Specified by:

remove in interface MutableNetwork

Parameters:

arc - The arc to be removed

modified

public void modified(ArcCompanion companion)

Description copied from interface: MutableNetwork

Tells the network that an arc has been modified. The network will then restore the arc upon backtracking.

Specified by:

modified in interface MutableNetwork

Parameters:

companion - The arc that was modified

increaseLevel

public void increaseLevel()

backtrack

public void backtrack()

changeCostOffset

public void changeCostOffset(long delta)

Description copied from interface: MutableNetwork

Changes the cost offset by some value.

Specified by:

changeCostOffset in interface MutableNetwork

Parameters:

delta - the change in cost

cost

public long cost(long cutoff)

Overrides:

cost in class NetworkSimplex

getStoreLevel

public int getStoreLevel()

Description copied from interface: MutableNetwork

Retrieves the current store level for domain pruning.

Specified by:

getStoreLevel in interface MutableNetwork

Returns:

the store level

needsUpdate

public boolean needsUpdate(int maxCost)