org.chocosolver.solver.propagation

Interface IPropagationEngine

All Superinterfaces:

Serializable

All Known Implementing Classes:

NoPropagationEngine, SevenQueuesPropagatorEngine, TwoBucketPropagationEngine

public interface IPropagationEngine
extends Serializable

An interface for propagation engines, it defines every required services.

Since:

05/12/11

Author:

Charles Prud'homme

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	IPropagationEngine.Trace

Field Summary

Fields

Modifier and Type	Field and Description
static org.slf4j.Logger	LOGGER

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)

Field Detail

LOGGER

static final org.slf4j.Logger LOGGER

Method Detail

initialize

void initialize()

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.

isInitialized

boolean isInitialized()

Is the engine initialized? Important for dynamic addition of constraints

Returns:

true if the engine has been initialized

propagate

void propagate()
               throws ContradictionException

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

Throws:

ContradictionException - if a contradiction occurrs

flush

void flush()

Flush this, ie. remove every pending events

fails

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

Throws:

ContradictionException

getContradictionException

ContradictionException getContradictionException()

clear

void clear()

onVariableUpdate

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

Take into account the modification of a variable

Parameters:

variable - modified variable

type - type of modification event

Throws:

ContradictionException

delayedPropagation

void delayedPropagation(Propagator propagator,
                      PropagatorEventType type)
                        throws ContradictionException

Throws:

ContradictionException

onPropagatorExecution

void onPropagatorExecution(Propagator propagator)

desactivatePropagator

void desactivatePropagator(Propagator propagator)

Set the propagator as inactivated within the propagation engine

Parameters:

propagator - propagator to desactivate

dynamicAddition

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

Add a constraint to the propagation engine

Parameters:

permanent - does the constraint is permanently added

ps - propagators to add

updateInvolvedVariables

void updateInvolvedVariables(Propagator p)

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

Parameters:

p - a propagator

propagateOnBacktrack

void propagateOnBacktrack(Propagator p)

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

Parameters:

p - a propagator

dynamicDeletion

void dynamicDeletion(Propagator... ps)

Delete the list of propagators in input from the engine

Parameters:

ps - a list of propagators