org.jacop.constraints

Class Circuit

java.lang.Object

org.jacop.constraints.DecomposedConstraint<Constraint>

org.jacop.constraints.Constraint

org.jacop.constraints.Alldifferent

org.jacop.constraints.Alldiff

org.jacop.constraints.Circuit

All Implemented Interfaces:

SatisfiedPresent, Stateful, UsesQueueVariable

public class Circuit
extends Alldiff
implements Stateful

Circuit constraint assures that all variables build a Hamiltonian circuit. Value of every variable x[i] points to the next variable in the circuit. Variables create one circuit.

Version:

4.9

Author:

Krzysztof Kuchcinski and Radoslaw Szymanek

Field Summary

Fields inherited from class org.jacop.constraints.Alldifferent

grounded, list, positionMapping

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
Circuit(IntVar[] list) It constructs a circuit constraint.
Circuit(List<IntVar> list) It constructs a circuit constraint.

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	impose(Store store) It imposes the constraint in a given store.
void	removeLevel(int level) This function is called in case of the backtrack, so a constraint can clear the queue of changed variables which is no longer valid.
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.Alldiff

queueVariable

Methods inherited from class org.jacop.constraints.Alldifferent

notSatisfied

Methods inherited from class org.jacop.constraints.Constraint

afc, arguments, cleanAfterFailure, decompose, getConsistencyPruningEvent, getGuideConstraint, getGuideValue, getGuideVariable, grounded, grounded, id, 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

Methods inherited from interface org.jacop.api.Stateful

isStateful

Constructor Detail

Circuit

public Circuit(IntVar[] list)

It constructs a circuit constraint.

Parameters:

list - variables which must form a circuit.

Circuit

public Circuit(List<IntVar> list)

It constructs a circuit constraint.

Parameters:

list - variables which must form a circuit.

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.

Overrides:

consistency in class Alldiff

Parameters:

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

getDefaultConsistencyPruningEvent

public int getDefaultConsistencyPruningEvent()

Overrides:

getDefaultConsistencyPruningEvent in class Alldiff

impose

public void impose(Store store)

Description copied from class: Constraint

It imposes the constraint in a given store.

Overrides:

impose in class Alldiff

Parameters:

store - the constraint store to which the constraint is imposed to.

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

Overrides:

satisfied in class Alldifferent

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 Alldiff

removeLevel

public void removeLevel(int level)

Description copied from interface: Stateful

This function is called in case of the backtrack, so a constraint can clear the queue of changed variables which is no longer valid. This function is called *before* all timestamps, variables, mutablevariables have reverted to their previous value.

Specified by:

removeLevel in interface Stateful

Parameters:

level - the level which is being removed.