choco.integer.constraints
Class EqualXC

java.lang.Object
  choco.AbstractEntity
      choco.AbstractConstraint
          choco.integer.constraints.AbstractIntConstraint
              choco.integer.constraints.AbstractUnIntConstraint
                  choco.integer.constraints.EqualXC

All Implemented Interfaces:

Constraint, Entity, IntConstraint, IntVarEventListener, VarEventListener, Propagator, java.lang.Cloneable, java.util.EventListener

public class EqualXC
extends AbstractUnIntConstraint

Implements a constraint X = C, with X a variable and C a constant.

Field Summary

protected int

cste The search constant of the constraint

Fields inherited from class choco.integer.constraints.AbstractUnIntConstraint

cIdx0, v0

Fields inherited from class choco.integer.constraints.AbstractIntConstraint

logger

Fields inherited from class choco.AbstractConstraint

active, constAwakeEvent, hook, priority

Fields inherited from class choco.AbstractEntity

problem

Constructor Summary

EqualXC(IntDomainVar x0, int c)
Constructs the constraint with the specified variables and constant.

Method Summary

void	awakeOnInf(int idx) Default propagation on improved lower bound: propagation on domain revision.
void	awakeOnInst(int idx) Default propagation on instantiation: full constraint re-propagation.
void	awakeOnRem(int idx, int x) Default propagation on one value removal: propagation on domain revision.
void	awakeOnSup(int idx) Default propagation on improved upper bound: propagation on domain revision.
void	awakeOnVar(int idx) Default propagation on variable revision: full constraint re-propagation.
java.lang.Object	clone() returns a copy of the constraint.
boolean	isConsistent() tests if the constraint is consistent with respect to the current state of domains
java.lang.Boolean	isEntailed() Checks if the listeners must be checked or must fail.
boolean	isEquivalentTo(Constraint compareTo) tests the equivalence (logical equality of the conditions) between two constraints.
boolean	isSatisfied() Checks if the constraint is satisfied when the variables are instantiated.
AbstractConstraint	opposite() computes the constraint modelling the counter-opposite condition of this
java.lang.String	pretty() Pretty print of the constraint.
void	propagate() The one and only propagation method.

Methods inherited from class choco.integer.constraints.AbstractUnIntConstraint

assignIndices, getConstraintIdx, getIntVar, getNbVars, getVar, isCompletelyInstantiated, setConstraintIndex, setVar

Methods inherited from class choco.integer.constraints.AbstractIntConstraint

awakeOnBounds, awakeOnRemovals, getSelfIndex

Methods inherited from class choco.AbstractConstraint

addListener, awake, connectVar, constAwake, delete, fail, getEvent, getPlugIn, getPriority, getProblem, getVarIdxInOpposite, isActive, setActive, setEntailed, setPassive, setPlugIn, substituteVar

Methods inherited from class java.lang.Object

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

Methods inherited from interface choco.Propagator

awake, constAwake, delete, getEvent, getPlugIn, getPriority

Methods inherited from interface choco.prop.VarEventListener

addListener, isActive, setActive, setPassive

Methods inherited from interface choco.prop.VarEventListener

addListener, isActive, setActive, setPassive

Field Detail

cste

protected final int cste

The search constant of the constraint

Constructor Detail

EqualXC

public EqualXC(IntDomainVar x0,
               int c)

Constructs the constraint with the specified variables and constant.

Parameters:

x0 - the search valued domain variable

c - the search constant used in the equality.

Method Detail

clone

public java.lang.Object clone()
                       throws java.lang.CloneNotSupportedException

Description copied from interface: Constraint

returns a copy of the constraint. This copy is a new object, may be a recursive copy in case of composite constraints. The original and the copy share the same variables & plugins

Specified by:

clone in interface Constraint

Overrides:

clone in class AbstractConstraint

Returns:

Throws:

java.lang.CloneNotSupportedException

pretty

public java.lang.String pretty()

Pretty print of the constraint.

Specified by:

pretty in interface Entity

Overrides:

pretty in class AbstractEntity

Returns:

a readable string representation of the object

propagate

public void propagate()
               throws ContradictionException

The one and only propagation method.
Note that after the first propagation, the constraint could be set passive (to prevent from further calls to propagation methods), but this management seems too heavy to be worthwhile

Specified by:

propagate in interface Propagator

Overrides:

propagate in class AbstractUnIntConstraint

Throws:

ContradictionException

awakeOnVar

public void awakeOnVar(int idx)
                throws ContradictionException

Description copied from class: AbstractConstraint

Default propagation on variable revision: full constraint re-propagation.

Specified by:

awakeOnVar in interface VarEventListener

Specified by:

awakeOnVar in interface Propagator

Overrides:

awakeOnVar in class AbstractConstraint

Throws:

ContradictionException

awakeOnInf

public void awakeOnInf(int idx)
                throws ContradictionException

Description copied from class: AbstractIntConstraint

Default propagation on improved lower bound: propagation on domain revision.

Specified by:

awakeOnInf in interface IntVarEventListener

Overrides:

awakeOnInf in class AbstractIntConstraint

Throws:

ContradictionException

awakeOnSup

public void awakeOnSup(int idx)
                throws ContradictionException

Description copied from class: AbstractIntConstraint

Default propagation on improved upper bound: propagation on domain revision.

Specified by:

awakeOnSup in interface IntVarEventListener

Overrides:

awakeOnSup in class AbstractIntConstraint

Throws:

ContradictionException

awakeOnInst

public void awakeOnInst(int idx)
                 throws ContradictionException

Description copied from class: AbstractIntConstraint

Default propagation on instantiation: full constraint re-propagation.

Specified by:

awakeOnInst in interface IntVarEventListener

Overrides:

awakeOnInst in class AbstractIntConstraint

Throws:

ContradictionException

awakeOnRem

public void awakeOnRem(int idx,
                       int x)
                throws ContradictionException

Description copied from class: AbstractIntConstraint

Default propagation on one value removal: propagation on domain revision.

Specified by:

awakeOnRem in interface IntVarEventListener

Overrides:

awakeOnRem in class AbstractIntConstraint

Throws:

ContradictionException

isEntailed

public java.lang.Boolean isEntailed()

Checks if the listeners must be checked or must fail.

Specified by:

isEntailed in interface Propagator

Overrides:

isEntailed in class AbstractConstraint

isSatisfied

public boolean isSatisfied()

Checks if the constraint is satisfied when the variables are instantiated.

isConsistent

public boolean isConsistent()

tests if the constraint is consistent with respect to the current state of domains

Specified by:

isConsistent in interface Propagator

Overrides:

isConsistent in class AbstractIntConstraint

Returns:

true iff the constraint is bound consistent (same as arc consistent)

opposite

public AbstractConstraint opposite()

Description copied from interface: Constraint

computes the constraint modelling the counter-opposite condition of this

Specified by:

opposite in interface Constraint

Overrides:

opposite in class AbstractConstraint

Returns:

a new constraint (modelling the opposite condition)

isEquivalentTo

public final boolean isEquivalentTo(Constraint compareTo)

Description copied from interface: Constraint

tests the equivalence (logical equality of the conditions) between two constraints. In particular whenever c1.equals(c2), then c1.isEquivalent(c2).

Specified by:

isEquivalentTo in interface Constraint

Overrides:

isEquivalentTo in class AbstractConstraint

Parameters:

compareTo - the constraint to be compared to

Returns:

true if and only if the constraints model the same logical condition.