Package org.jacop.satwrapper

Class SatChangesListener

java.lang.Object

org.jacop.satwrapper.SatChangesListener

All Implemented Interfaces:

SolverComponent, AssertionListener, BackjumpListener, PropagateListener

public final class SatChangesListener
extends java.lang.Object
implements AssertionListener, PropagateListener, BackjumpListener

this class listens to changes in literals in SAT solver, and reminds what changes this implies for CP variables

Version:

4.8

Field Summary

Fields

Modifier and Type	Field	Description
private java.util.Set<BooleanVar>	booleanVarsToUpdate
private Core	core
private java.util.Set<java.lang.Integer>[]	excludedValues
private java.util.BitSet	intVarsToUpdate
private java.lang.Integer[]	lowerBounds
private java.lang.Integer[]	upperBounds
private SatWrapper	wrapper

Constructor Summary

Constructors

Constructor	Description
SatChangesListener()

Method Summary

Modifier and Type	Method	Description
void	clear()	clears all sets, so that elements occurring in them later result only from later events
void	ensureAccess(IntVar cpVar)	gets sure we won't have a NullPointerException
void	initialize(Core core)	initializes the component with the given solver.
void	initialize(SatWrapper wrapper)
private void	onAssertion(int literal)	this should be called every time a new boolean variable representing a CP proposition is asserted, but preferably only once per variable, so that it can later update the CP variables domains
void	onAssertion(int literal, int level)	Called when a variable is set
void	onBackjump(int oldLevel, int newLevel)	clear on backjump
void	onPropagate(int literal, int clauseId)	called when a propagation occurs
void	onRestart(int oldLevel)	called when the solver restarts.
java.lang.String	toString()
void	updateCpVariables(int storeLevel)	Using all data accumulated since last clear(), update the domain of the given CP variable

Methods inherited from class java.lang.Object

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

Field Detail

wrapper

private SatWrapper wrapper

core

private Core core

excludedValues

private java.util.Set<java.lang.Integer>[] excludedValues

upperBounds

private java.lang.Integer[] upperBounds

lowerBounds

private java.lang.Integer[] lowerBounds

intVarsToUpdate

private java.util.BitSet intVarsToUpdate

booleanVarsToUpdate

private java.util.Set<BooleanVar> booleanVarsToUpdate

Constructor Detail

SatChangesListener

public SatChangesListener()

Method Detail

clear

public void clear()

clears all sets, so that elements occurring in them later result only from later events

onPropagate

public void onPropagate(int literal,
                        int clauseId)

Description copied from interface: PropagateListener

called when a propagation occurs

Specified by:

onPropagate in interface PropagateListener

Parameters:

literal - the literal propagated

clauseId - the unique ID of the unit clause

onAssertion

public void onAssertion(int literal,
                        int level)

Description copied from interface: AssertionListener

Called when a variable is set

Specified by:

onAssertion in interface AssertionListener

Parameters:

literal - the literal that is set propagation, false otherwise

level - the search level

onBackjump

public void onBackjump(int oldLevel,
                       int newLevel)

clear on backjump

Specified by:

onBackjump in interface BackjumpListener

Parameters:

oldLevel - the level at which the solver was before backtracking

newLevel - the level to which the solver backtracks

onRestart

public void onRestart(int oldLevel)

Description copied from interface: BackjumpListener

called when the solver restarts.

components that want to be warned about restarts should put themselves in Core.restartModules.

Specified by:

onRestart in interface BackjumpListener

Parameters:

oldLevel - the level at which the solver was before restarting

onAssertion

private void onAssertion(int literal)

this should be called every time a new boolean variable representing a CP proposition is asserted, but preferably only once per variable, so that it can later update the CP variables domains

Parameters:

literal - the boolean literal that has been asserted

updateCpVariables

public void updateCpVariables(int storeLevel)

Using all data accumulated since last clear(), update the domain of the given CP variable

Parameters:

storeLevel - the current level of the store

ensureAccess

public void ensureAccess(IntVar cpVar)

gets sure we won't have a NullPointerException

Parameters:

cpVar - the CP variable we are about to access

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

initialize

public void initialize(Core core)

Description copied from interface: SolverComponent

initializes the component with the given solver. May be called only once. This method must register the component to the solver for the run.

Specified by:

initialize in interface SolverComponent

Parameters:

core - core component to initialize

initialize

public void initialize(SatWrapper wrapper)