org.cpsolver.ifs.algorithms

Class NeighbourSearch.NeighbourSearchContext

java.lang.Object

org.cpsolver.ifs.algorithms.NeighbourSearch.NeighbourSearchContext

All Implemented Interfaces:

AssignmentContext, SolutionListener<V,T>

Direct Known Subclasses:

GreatDeluge.GreatDelugeContext, HillClimber.HillClimberContext, SimulatedAnnealing.SimulatedAnnealingContext

Enclosing class:

NeighbourSearch<V extends Variable<V,T>,T extends Value<V,T>>

public abstract class NeighbourSearch.NeighbourSearchContext
extends Object
implements AssignmentContext, SolutionListener<V,T>

Search context

Field Summary

Fields

Modifier and Type	Field and Description
protected int	iIter
protected long	iT0

Constructor Summary

Constructors

Constructor and Description
NeighbourSearchContext()

Method Summary

Modifier and Type	Method and Description
protected abstract boolean	accept(Assignment<V,T> assignment, Model<V,T> model, Neighbour<V,T> neighbour, double value, boolean lazy) Acceptance criterion.
protected void	activate(Solution<V,T> solution) Called just before the neighbourhood search is called for the first time.
void	bestCleared(Solution<V,T> solution) Called by the solution when method Solution.clearBest() is called.
void	bestRestored(Solution<V,T> solution) Called by the solution when method Solution.restoreBest() is called.
void	bestSaved(Solution<V,T> solution) Called by the solution when method Solution.saveBest() is called.
protected boolean	canContinue(Solution<V,T> solution) Return false if the search is to be stopped.
protected void	deactivate(Solution<V,T> solution) Called when the search cannot continue, just before a null neighbour is returned
void	getInfo(Solution<V,T> solution, Map<String,String> info) Called by the solution when it is asked to produce info table, see Solution.getInfo().
void	getInfo(Solution<V,T> solution, Map<String,String> info, Collection<V> variables) Called by the solution when it is asked to produce info table, see Solution.getInfo().
protected long	getTimeMillis() Running time in milliseconds (since the last call of activate)
protected void	incIteration(Solution<V,T> solution) Increment iteration counters etc.
void	solutionUpdated(Solution<V,T> solution) Called by the solution when it is updated, see Solution.update(double).

Methods inherited from class java.lang.Object

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

Field Detail

iT0

protected long iT0

iIter

protected int iIter

Constructor Detail

NeighbourSearchContext

public NeighbourSearchContext()

Method Detail

activate

protected void activate(Solution<V,T> solution)

Called just before the neighbourhood search is called for the first time.

Parameters:

solution - current solution

deactivate

protected void deactivate(Solution<V,T> solution)

Called when the search cannot continue, just before a null neighbour is returned

Parameters:

solution - current solution

incIteration

protected void incIteration(Solution<V,T> solution)

Increment iteration counters etc.

Parameters:

solution - current solution

getTimeMillis

protected long getTimeMillis()

Running time in milliseconds (since the last call of activate)

Returns:

running time

canContinue

protected boolean canContinue(Solution<V,T> solution)

Return false if the search is to be stopped. Null neighbour is returned when this method returns false.

Parameters:

solution - current solution

Returns:

true if can continue

accept

protected abstract boolean accept(Assignment<V,T> assignment,
                                  Model<V,T> model,
                                  Neighbour<V,T> neighbour,
                                  double value,
                                  boolean lazy)

Acceptance criterion. If lazy, current assignment already contains the given neighbour.

Parameters:

assignment - current assignment

model - problem model

neighbour - a generated move

value - value of the generated move (i.e., its impact on the solution value)

lazy - true if lazy move

Returns:

true if the generated move is to be assigned

bestSaved

public void bestSaved(Solution<V,T> solution)

Description copied from interface: SolutionListener

Called by the solution when method Solution.saveBest() is called.

Specified by:

bestSaved in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

solution - source solution

solutionUpdated

public void solutionUpdated(Solution<V,T> solution)

Description copied from interface: SolutionListener

Called by the solution when it is updated, see Solution.update(double).

Specified by:

solutionUpdated in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

solution - source solution

getInfo

public void getInfo(Solution<V,T> solution,
                    Map<String,String> info)

Description copied from interface: SolutionListener

Called by the solution when it is asked to produce info table, see Solution.getInfo(). A listener can also add some its info into this table.

Specified by:

getInfo in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

solution - source solution

info - produced info table

getInfo

public void getInfo(Solution<V,T> solution,
                    Map<String,String> info,
                    Collection<V> variables)

Description copied from interface: SolutionListener

Called by the solution when it is asked to produce info table, see Solution.getInfo(). A listener can also add some its info into this table.

Specified by:

getInfo in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

solution - source solution

info - produced info table

variables - only variables from this set are included

bestCleared

public void bestCleared(Solution<V,T> solution)

Description copied from interface: SolutionListener

Called by the solution when method Solution.clearBest() is called.

Specified by:

bestCleared in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

solution - source solution

bestRestored

public void bestRestored(Solution<V,T> solution)

Description copied from interface: SolutionListener

Called by the solution when method Solution.restoreBest() is called.

Specified by:

bestRestored in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

solution - source solution