org.jacop.set.constraints

Class AunionBeqC

java.lang.Object

org.jacop.constraints.DecomposedConstraint<Constraint>

org.jacop.constraints.Constraint

org.jacop.set.constraints.AunionBeqC

All Implemented Interfaces:

SatisfiedPresent, UsesQueueVariable

public class AunionBeqC
extends Constraint
implements UsesQueueVariable, SatisfiedPresent

It creates a constraint that makes sure that A union B is equal to C. A \/ B = C.

Version:

4.9

Author:

Radoslaw Szymanek and Krzysztof Kuchcinski

Field Summary

Fields

Modifier and Type	Field and Description
SetVar	a It specifies set variable a.
SetVar	b It specifies set variable b.
SetVar	c It specifies set variable c.
boolean	performCardinalityReasoning It specifies if the constrain attempts to perform expensive and yet unlikely propagation due to cardinality information.

Fields inherited from class org.jacop.constraints.Constraint

atomicExecution, consistencyPruningEvents, constraintScope, earlyTerminationOK, increaseWeight, numberId, scope, trace

Fields inherited from class org.jacop.constraints.DecomposedConstraint

queueIndex

Constructor Summary

Constructors

Constructor and Description
AunionBeqC(SetVar a, SetVar b, SetVar c) It constructs an AunionBeqC constraint to restrict the domain of the variables A, B and C.

Method Summary

Modifier and Type	Method and Description
void	consistency(Store store) It is a (most probably incomplete) consistency function which removes the values from variables domains.
int	getDefaultConsistencyPruningEvent()
void	queueVariable(int level, Var variable) This is a function called to indicate which variable in a scope of constraint has changed.
boolean	satisfied() It checks if the constraint is satisfied.
String	toString() It produces a string representation of a constraint state.

Methods inherited from class org.jacop.constraints.Constraint

afc, arguments, cleanAfterFailure, decompose, getConsistencyPruningEvent, getGuideConstraint, getGuideValue, getGuideVariable, grounded, grounded, id, impose, impose, imposeDecomposition, increaseWeight, intArrayToString, long2int, numberArgs, removeConstraint, requiresMonotonicity, setConsistencyPruningEvent, setConstraintScope, setScope, setScope, setScope, setScope, setScope, setWatchedVariableGrounded, supplyGuideFeedback, updateAFC, watchedVariableGrounded

Methods inherited from class org.jacop.constraints.DecomposedConstraint

auxiliaryVariables, checkInput, checkInput, checkInputForDuplication, checkInputForDuplicationSkipSingletons, checkInputForNullness, checkInputForNullness, checkInputForNullness, derivative, getDubletonsSkipSingletons, imposeDecomposition

Methods inherited from class java.lang.Object

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

Field Detail

a

public SetVar a

It specifies set variable a.

b

public SetVar b

It specifies set variable b.

c

public SetVar c

It specifies set variable c.

performCardinalityReasoning

public boolean performCardinalityReasoning

It specifies if the constrain attempts to perform expensive and yet unlikely propagation due to cardinality information.

Constructor Detail

AunionBeqC

public AunionBeqC(SetVar a,
                  SetVar b,
                  SetVar c)

It constructs an AunionBeqC constraint to restrict the domain of the variables A, B and C.

Parameters:

a - variable representing the first parameter

b - variable representing the second parameter

c - variable that is restricted to be the union of a and b.

Method Detail

consistency

public void consistency(Store store)

Description copied from class: Constraint

It is a (most probably incomplete) consistency function which removes the values from variables domains. Only values which do not have any support in a solution space are removed.

Specified by:

consistency in class Constraint

Parameters:

store - constraint store within which the constraint consistency is being checked.

getDefaultConsistencyPruningEvent

public int getDefaultConsistencyPruningEvent()

Specified by:

getDefaultConsistencyPruningEvent in class Constraint

satisfied

public boolean satisfied()

Description copied from interface: SatisfiedPresent

It checks if the constraint is satisfied. It can return false even if constraint is satisfied but not all variables in its scope are grounded. It needs to return true if all variables in its scope are grounded and constraint is satisfied.

Implementations of this interface for constraints that are not PrimitiveConstraint may require constraint imposition and consistency check as a requirement to work correctly.

Specified by:

satisfied in interface SatisfiedPresent

Returns:

true if constraint is possible to verify that it is satisfied.

toString

public String toString()

Description copied from class: Constraint

It produces a string representation of a constraint state.

Overrides:

toString in class Constraint

queueVariable

public void queueVariable(int level,
                          Var variable)

Description copied from class: Constraint

This is a function called to indicate which variable in a scope of constraint has changed. It also indicates a store level at which the change has occurred.

Overrides:

queueVariable in class Constraint

Parameters:

level - the level of the store at which the change has occurred.

variable - variable which has changed.