org.chocosolver.solver.propagation.hardcoded

Class SevenQueuesPropagatorEngine

java.lang.Object

org.chocosolver.solver.propagation.hardcoded.SevenQueuesPropagatorEngine

All Implemented Interfaces:

Serializable, IPropagationEngine

public class SevenQueuesPropagatorEngine
extends Object
implements IPropagationEngine

This engine is priority-driven constraint-oriented seven queues engine.
On a call to onVariableUpdate, it stores the event generated and schedules the propagator in one of the 7 queues wrt to its priority for future revision.

Since:

05/07/12

Author:

Charles Prud'homme

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface org.chocosolver.solver.propagation.IPropagationEngine

IPropagationEngine.Trace

Field Summary

Fields

Modifier and Type	Field and Description
protected IEnvironment	environment
protected int[][]	eventmasks
protected IntCircularQueue[]	eventsets
protected ContradictionException	exception
protected Propagator	lastProp
protected int	notEmpty
protected IId2AbId	p2i
protected CircularQueue<Propagator>[]	pro_queue
protected Propagator[]	propagators
protected short[]	scheduled

Constructor Summary

Constructors

Constructor and Description
SevenQueuesPropagatorEngine(Solver solver)

Method Summary

Methods

Modifier and Type	Method and Description
void	clear()
void	delayedPropagation(Propagator propagator, PropagatorEventType type)
void	desactivatePropagator(Propagator propagator) Set the propagator as inactivated within the propagation engine
void	dynamicAddition(boolean permanent, Propagator... ps) Add a constraint to the propagation engine
void	dynamicDeletion(Propagator... ps) Delete the list of propagators in input from the engine
void	fails(ICause cause, Variable variable, String message)
void	flush() Flush this, ie. remove every pending events
ContradictionException	getContradictionException()
void	initialize() Build up internal structure, if not yet done, in order to allow propagation.
boolean	isInitialized() Is the engine initialized?
void	onPropagatorExecution(Propagator propagator)
void	onVariableUpdate(Variable variable, IEventType type, ICause cause) Take into account the modification of a variable
void	propagate() Launch the proapagation, ie, active propagators if necessary, then reach a fix point
void	propagateOnBacktrack(Propagator p) State that the propagator needs to be propagated (coarse event) on backtrack.
void	updateInvolvedVariables(Propagator p) Update the scope of variable of a propagator (addition or deletion are allowed -- p.vars are scanned)

Methods inherited from class java.lang.Object

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

Field Detail

exception

protected final ContradictionException exception

environment

protected final IEnvironment environment

propagators

protected Propagator[] propagators

pro_queue

protected final CircularQueue<Propagator>[] pro_queue

lastProp

protected Propagator lastProp

p2i

protected IId2AbId p2i

notEmpty

protected int notEmpty

scheduled

protected short[] scheduled

eventsets

protected IntCircularQueue[] eventsets

eventmasks

protected int[][] eventmasks

Constructor Detail

SevenQueuesPropagatorEngine

public SevenQueuesPropagatorEngine(Solver solver)

Method Detail

fails

public void fails(ICause cause,
         Variable variable,
         String message)
           throws ContradictionException

Specified by:

fails in interface IPropagationEngine

Throws:

ContradictionException

getContradictionException

public ContradictionException getContradictionException()

Specified by:

getContradictionException in interface IPropagationEngine

initialize

public void initialize()

Description copied from interface: IPropagationEngine

Build up internal structure, if not yet done, in order to allow propagation. If new constraints are added after having initializing the engine, dynamic addition is used. A call to clear erase the internal structure, and allow new initialisation.

Specified by:

initialize in interface IPropagationEngine

isInitialized

public boolean isInitialized()

Description copied from interface: IPropagationEngine

Is the engine initialized? Important for dynamic addition of constraints

Specified by:

isInitialized in interface IPropagationEngine

Returns:

true if the engine has been initialized

propagate

public void propagate()
               throws ContradictionException

Description copied from interface: IPropagationEngine

Launch the proapagation, ie, active propagators if necessary, then reach a fix point

Specified by:

propagate in interface IPropagationEngine

Throws:

ContradictionException - if a contradiction occurrs

flush

public void flush()

Description copied from interface: IPropagationEngine

Flush this, ie. remove every pending events

Specified by:

flush in interface IPropagationEngine

onVariableUpdate

public void onVariableUpdate(Variable variable,
                    IEventType type,
                    ICause cause)
                      throws ContradictionException

Description copied from interface: IPropagationEngine

Take into account the modification of a variable

Specified by:

onVariableUpdate in interface IPropagationEngine

Parameters:

variable - modified variable

type - type of modification event

Throws:

ContradictionException

delayedPropagation

public void delayedPropagation(Propagator propagator,
                      PropagatorEventType type)
                        throws ContradictionException

Specified by:

delayedPropagation in interface IPropagationEngine

Throws:

ContradictionException

onPropagatorExecution

public void onPropagatorExecution(Propagator propagator)

Specified by:

onPropagatorExecution in interface IPropagationEngine

desactivatePropagator

public void desactivatePropagator(Propagator propagator)

Description copied from interface: IPropagationEngine

Set the propagator as inactivated within the propagation engine

Specified by:

desactivatePropagator in interface IPropagationEngine

Parameters:

propagator - propagator to desactivate

clear

public void clear()

Specified by:

clear in interface IPropagationEngine

dynamicAddition

public void dynamicAddition(boolean permanent,
                   Propagator... ps)

Description copied from interface: IPropagationEngine

Add a constraint to the propagation engine

Specified by:

dynamicAddition in interface IPropagationEngine

Parameters:

permanent - does the constraint is permanently added

ps - propagators to add

updateInvolvedVariables

public void updateInvolvedVariables(Propagator p)

Description copied from interface: IPropagationEngine

Update the scope of variable of a propagator (addition or deletion are allowed -- p.vars are scanned)

Specified by:

updateInvolvedVariables in interface IPropagationEngine

Parameters:

p - a propagator

propagateOnBacktrack

public void propagateOnBacktrack(Propagator p)

Description copied from interface: IPropagationEngine

State that the propagator needs to be propagated (coarse event) on backtrack. For dynamic propagator only, such as PropSat or PropNogoods.

Specified by:

propagateOnBacktrack in interface IPropagationEngine

Parameters:

p - a propagator

dynamicDeletion

public void dynamicDeletion(Propagator... ps)

Description copied from interface: IPropagationEngine

Delete the list of propagators in input from the engine

Specified by:

dynamicDeletion in interface IPropagationEngine

Parameters:

ps - a list of propagators