org.cpsolver.ifs.assignment.context

Class ModelWithContext<V extends Variable<V,T>,T extends Value<V,T>,C extends AssignmentConstraintContext<V,T>>

java.lang.Object

org.cpsolver.ifs.model.Model<V,T>

org.cpsolver.ifs.assignment.context.ModelWithContext<V,T,C>

Type Parameters:

V - Variable

T - Value

C - Assignment Context

All Implemented Interfaces:

CanHoldContext, HasAssignmentContext<V,T,C>

Direct Known Subclasses:

ExamModel, StudentSectioningModel

public abstract class ModelWithContext<V extends Variable<V,T>,T extends Value<V,T>,C extends AssignmentConstraintContext<V,T>>
extends Model<V,T>
implements HasAssignmentContext<V,T,C>, CanHoldContext

A model with an assignment context. In order to be able to hold multiple assignments in memory it is desired for all the assignment dependent data a constraint may need (to effectively enumerate problem objectives), to store these data in a separate class (implementing the AssignmentConstraintContext interface). This context is created by calling HasAssignmentContext.createAssignmentContext(Assignment) and accessed by ConstraintWithContext.getContext(Assignment).

Version:

IFS 1.3 (Iterative Forward Search)
Copyright (C) 2014 Tomáš Müller
muller@unitime.org
http://muller.unitime.org

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 3 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 see http://www.gnu.org/licenses.

Author:

Tomáš Müller

See Also:

AssignmentContext

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	ModelWithContext.ContextUpdateType Defines how the context of the model should be automatically updated (i.e., when AssignmentConstraintContext.assigned(Assignment, Value) and AssignmentConstraintContext.unassigned(Assignment, Value) are called).

Field Summary

Fields inherited from class org.cpsolver.ifs.model.Model

sDoubleFormat, sPercentageFormat, sTimeFormat

Fields inherited from interface org.cpsolver.ifs.assignment.context.CanHoldContext

sMaxSize

Constructor Summary

Constructors

Constructor and Description
ModelWithContext()

Method Summary

Modifier and Type	Method and Description
void	afterAssigned(Assignment<V,T> assignment, long iteration, T value) Called after a value is assigned to its variable
void	afterUnassigned(Assignment<V,T> assignment, long iteration, T value) Called after a value is unassigned from its variable
void	beforeAssigned(Assignment<V,T> assignment, long iteration, T value) Called before a value is assigned to its variable
void	beforeUnassigned(Assignment<V,T> assignment, long iteration, T value) Called before a value is unassigned from its variable
AssignmentContextReference<V,T,C>	getAssignmentContextReference() Returns an assignment context reference
AssignmentContext[]	getContext() An array of CanHoldContext.sMaxSize assignment contexts
C	getContext(Assignment<V,T> assignment) Returns an assignment context associated with this model.
ModelWithContext.ContextUpdateType	getContextUpdateType()
void	setAssignmentContextReference(AssignmentContextReference<V,T,C> reference) Store an assignment context reference that was given for the class by the Model.createReference(HasAssignmentContext).
void	setContextUpdateType(ModelWithContext.ContextUpdateType iContextUpdateType)

Methods inherited from class org.cpsolver.ifs.model.Model

addConstraint, addCriterion, addGlobalConstraint, addModelListener, addVariable, afterAssigned, afterUnassigned, assignedVariables, assignedVariables, beforeAssigned, beforeUnassigned, bestUnassignedVariables, bestUnassignedVariables, clearAssignmentContexts, clearBest, conflictConstraints, conflictValues, conflictValues, constraints, countConstraints, countGlobalConstraints, countVariables, createAssignmentContexts, createInheritedAssignment, createReference, getBestPerturbations, getBestUnassignedVariables, getBestValue, getCriteria, getCriterion, getDefaultAssignment, getEmptyAssignment, getExtendedInfo, getExtendedInfo, getInfo, getInfo, getInfo, getInfo, getInfoProviders, getModelListeners, getPerc, getPercRev, getTotalValue, getTotalValue, getTotalValue, getTotalValue, globalConstraints, inConflict, inConflict, init, invalidateVariablesWithInitialValueCache, modelListenerOfType, nrAssignedVariables, nrAssignedVariables, nrUnassignedVariables, nrUnassignedVariables, perturbVariables, perturbVariables, perturbVariables, perturbVariables, perturbVariables, removeConstraint, removeCriterion, removeCriterion, removeGlobalConstraint, removeModelListener, removeReference, removeVariable, restoreBest, restoreBest, restoreBest, saveBest, saveBest, setBestValue, setDefaultAssignment, toString, toString, unassignedHardConstraints, unassignedVariables, unassignedVariables, variables, variablesWithInitialValue, weaken

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.cpsolver.ifs.assignment.context.HasAssignmentContext

createAssignmentContext

Constructor Detail

ModelWithContext

public ModelWithContext()

Method Detail

getContext

public C getContext(Assignment<V,T> assignment)

Returns an assignment context associated with this model. If there is no assignment context associated with this model yet, one is created using the HasAssignmentContext.createAssignmentContext(Assignment) method. From that time on, this context is kept with the assignment and automatically updated by calling the AssignmentConstraintContext.assigned(Assignment, Value) and AssignmentConstraintContext.unassigned(Assignment, Value) whenever a variable is changed.

Specified by:

getContext in interface HasAssignmentContext<V extends Variable<V,T>,T extends Value<V,T>,C extends AssignmentConstraintContext<V,T>>

Parameters:

assignment - given assignment

Returns:

assignment context associated with this model and the given assignment

getAssignmentContextReference

public AssignmentContextReference<V,T,C> getAssignmentContextReference()

Description copied from interface: HasAssignmentContext

Returns an assignment context reference

Specified by:

getAssignmentContextReference in interface HasAssignmentContext<V extends Variable<V,T>,T extends Value<V,T>,C extends AssignmentConstraintContext<V,T>>

Returns:

reference provided by the model by calling Model.createReference(HasAssignmentContext) during initialization

setAssignmentContextReference

public void setAssignmentContextReference(AssignmentContextReference<V,T,C> reference)

Description copied from interface: HasAssignmentContext

Store an assignment context reference that was given for the class by the Model.createReference(HasAssignmentContext).

Specified by:

setAssignmentContextReference in interface HasAssignmentContext<V extends Variable<V,T>,T extends Value<V,T>,C extends AssignmentConstraintContext<V,T>>

Parameters:

reference - reference provided by the model by calling Model.createReference(HasAssignmentContext) during initialization

getContext

public AssignmentContext[] getContext()

Description copied from interface: CanHoldContext

An array of CanHoldContext.sMaxSize assignment contexts

Specified by:

getContext in interface CanHoldContext

Returns:

assignment contexts

beforeUnassigned

public void beforeUnassigned(Assignment<V,T> assignment,
                             long iteration,
                             T value)

Description copied from class: Model

Called before a value is unassigned from its variable

Overrides:

beforeUnassigned in class Model<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

assignment - current assignment

iteration - current iteration

value - a value to be unassigned

afterUnassigned

public void afterUnassigned(Assignment<V,T> assignment,
                            long iteration,
                            T value)

Description copied from class: Model

Called after a value is unassigned from its variable

Overrides:

afterUnassigned in class Model<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

assignment - current assignment

iteration - current iteration

value - a value that was unassigned

afterAssigned

public void afterAssigned(Assignment<V,T> assignment,
                          long iteration,
                          T value)

Description copied from class: Model

Called after a value is assigned to its variable

Overrides:

afterAssigned in class Model<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

assignment - current assignment

iteration - current iteration

value - a value that was assigned

beforeAssigned

public void beforeAssigned(Assignment<V,T> assignment,
                           long iteration,
                           T value)

Description copied from class: Model

Called before a value is assigned to its variable

Overrides:

beforeAssigned in class Model<V extends Variable<V,T>,T extends Value<V,T>>

Parameters:

assignment - current assignment

iteration - current iteration

value - a value to be assigned

getContextUpdateType

public ModelWithContext.ContextUpdateType getContextUpdateType()

setContextUpdateType

public void setContextUpdateType(ModelWithContext.ContextUpdateType iContextUpdateType)