net.sf.cpsolver.ifs.extension
Class Extension

java.lang.Object
  net.sf.cpsolver.ifs.extension.Extension

All Implemented Interfaces:

ModelListener

Direct Known Subclasses:

ConflictStatistics, DistanceConflict, MacPropagation, MacRevised, SearchIntensification, ViolatedInitials

public class Extension
extends Object
implements ModelListener

Generic extension of IFS solver.

All extensions should extend this class.

An extension may use extra information associated with a variable or a value (see Variable.setExtra(Object), Variable.getExtra(), Value.setExtra(Object), Value.getExtra()) but there can be only one extension using these extra objects used during the search. For instance, MacPropagation is using these extra objects to memorize explanations.

Version:

IFS 1.1 (Iterative Forward Search)
Copyright (C) 2006 Tomáš Müller
muller@unitime.org
Lazenska 391, 76314 Zlin, Czech Republic

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

Constructor Summary

Extension(Solver solver, DataProperties properties)
Constructor

Method Summary

void	afterAssigned(long iteration, Value value) Called after a value is assigned to a variable
void	afterUnassigned(long iteration, Value value) Called after a value is unassigned from a variable
void	beforeAssigned(long iteration, Value value) Called before a value is assigned to a variable
void	beforeUnassigned(long iteration, Value value) Called after a value is unassigned from a variable
void	constraintAdded(Constraint constraint) Called when a constraint is added to the model
void	constraintRemoved(Constraint constraint) Called when a constraint is removed from the model
Model	getModel() Returns the model
DataProperties	getProperties() Returns input configuration
Solver	getSolver() Returns the solver
boolean	init(Solver solver) Initialization -- called before the solver is started
boolean	isRegistered() Returns true if there is a model registered to this extension, i.e., when extension is registered.
void	register(Model model) Registration of a model.
void	unregister(Model model) Unregistration of a model.
boolean	useValueExtra() Should return true when Value.setExtra(Object), Value.getExtra() are used by the extension
boolean	useVariableExtra() Should return true when Variable.setExtra(Object), Variable.getExtra() are used by the extension
void	variableAdded(Variable variable) Called when a variable is added to the model
void	variableRemoved(Variable variable) Called when a variable is removed from the model

Methods inherited from class java.lang.Object

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

Constructor Detail

Extension

public Extension(Solver solver,
                 DataProperties properties)

Constructor

Parameters:

solver - IFS solver

properties - input configuration

Method Detail

register

public void register(Model model)

Registration of a model. This is called by the solver before start.

unregister

public void unregister(Model model)

Unregistration of a model. This is called by the solver when extension is removed.

isRegistered

public boolean isRegistered()

Returns true if there is a model registered to this extension, i.e., when extension is registered.

getModel

public Model getModel()

Returns the model

getSolver

public Solver getSolver()

Returns the solver

getProperties

public DataProperties getProperties()

Returns input configuration

afterAssigned

public void afterAssigned(long iteration,
                          Value value)

Called after a value is assigned to a variable

Specified by:

afterAssigned in interface ModelListener

Parameters:

iteration - current iteration

value - value to be assigned

afterUnassigned

public void afterUnassigned(long iteration,
                            Value value)

Called after a value is unassigned from a variable

Specified by:

afterUnassigned in interface ModelListener

Parameters:

iteration - current iteration

value - value to be unassigned

beforeAssigned

public void beforeAssigned(long iteration,
                           Value value)

Called before a value is assigned to a variable

Specified by:

beforeAssigned in interface ModelListener

Parameters:

iteration - current iteration

value - value to be assigned

beforeUnassigned

public void beforeUnassigned(long iteration,
                             Value value)

Called after a value is unassigned from a variable

Specified by:

beforeUnassigned in interface ModelListener

Parameters:

iteration - current iteration

value - value to be unassigned

constraintAdded

public void constraintAdded(Constraint constraint)

Called when a constraint is added to the model

Specified by:

constraintAdded in interface ModelListener

Parameters:

constraint - added constraint

constraintRemoved

public void constraintRemoved(Constraint constraint)

Called when a constraint is removed from the model

Specified by:

constraintRemoved in interface ModelListener

Parameters:

constraint - removed constraint

variableAdded

public void variableAdded(Variable variable)

Called when a variable is added to the model

Specified by:

variableAdded in interface ModelListener

Parameters:

variable - added variable

variableRemoved

public void variableRemoved(Variable variable)

Called when a variable is removed from the model

Specified by:

variableRemoved in interface ModelListener

Parameters:

variable - removed variable

init

public boolean init(Solver solver)

Initialization -- called before the solver is started

Specified by:

init in interface ModelListener

Parameters:

solver - IFS solver

useValueExtra

public boolean useValueExtra()

Should return true when Value.setExtra(Object), Value.getExtra() are used by the extension

useVariableExtra

public boolean useVariableExtra()

Should return true when Variable.setExtra(Object), Variable.getExtra() are used by the extension