org.jacop.constraints

Class Circuit

java.lang.Object

org.jacop.constraints.DecomposedConstraint

org.jacop.constraints.Constraint

org.jacop.constraints.Alldifferent

org.jacop.constraints.Alldiff

org.jacop.constraints.Circuit

public class Circuit
extends Alldiff

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:

4.2

Author:

Krzysztof Kuchcinski and Radoslaw Szymanek

Field Summary

Fields

Modifier and Type	Field and Description
static String[]	xmlAttributes It specifies the arguments required to be saved by an XML format as well as the constructor being called to recreate an object from an XML format.

Fields inherited from class org.jacop.constraints.Alldiff

listAlldiff

Fields inherited from class org.jacop.constraints.Alldifferent

grounded, list, positionMapping

Fields inherited from class org.jacop.constraints.Constraint

atomicExecution, consistencyPruningEvents, earlyTerminationOK, id, increaseWeight, numberArgs, numberId, trace

Fields inherited from class org.jacop.constraints.DecomposedConstraint

queueIndex

Constructor Summary

Constructors

Constructor and Description
Circuit(ArrayList<IntVar> list) It constructs a circuit constraint.
Circuit(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	getConsistencyPruningEvent(Var var) It retrieves the pruning event which causes reevaluation of the constraint.
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This function is called in case of the backtrack, so a constraint can clear the queue of changed variables which is no longer valid.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.Alldifferent

arguments, increaseWeight, queueVariable, removeConstraint

Methods inherited from class org.jacop.constraints.Constraint

cleanAfterFailure, decompose, getGuideConstraint, getGuideValue, getGuideVariable, id, impose, imposeDecomposition, numberArgs, removeLevelLate, requiresMonotonicity, setConsistencyPruningEvent, supplyGuideFeedback

Methods inherited from class org.jacop.constraints.DecomposedConstraint

auxiliaryVariables, derivative, imposeDecomposition

Methods inherited from class java.lang.Object

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

Field Detail

xmlAttributes

public static String[] xmlAttributes

It specifies the arguments required to be saved by an XML format as well as the constructor being called to recreate an object from an XML format.

Constructor Detail

Circuit

public Circuit(IntVar[] list)

It constructs a circuit constraint.

Parameters:

list - variables which must form a circuit.

Circuit

public Circuit(ArrayList<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.

getConsistencyPruningEvent

public int getConsistencyPruningEvent(Var var)

Description copied from class: Constraint

It retrieves the pruning event which causes reevaluation of the constraint.

Overrides:

getConsistencyPruningEvent in class Alldiff

Parameters:

var - variable for which pruning event is retrieved

Returns:

it returns the int code of the pruning event (GROUND, BOUND, ANY, NONE)

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 class: Constraint

It checks if the constraint is satisfied. If this function is incorrectly implemented a constraint may not be satisfied in a solution.

Overrides:

satisfied in class Alldifferent

Returns:

true if the constraint is for certain satisfied, false otherwise.

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 class: Constraint

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.

Overrides:

removeLevel in class Constraint

Parameters:

level - the level which is being removed.