choco.palm.dbt.explain
Class GenericExplanation

java.lang.Object
  choco.palm.dbt.explain.GenericExplanation

All Implemented Interfaces:

ConstraintCollection, PalmExplanation, Explanation

Direct Known Subclasses:

AbstractBoundExplanation, AbstractRealBoundExplanation, RemovalExplanation

public class GenericExplanation
extends java.lang.Object
implements PalmExplanation

Generic implementation of explanations. It is used by filtering algorithms before specializing them for specific use (bound modification, value removal, contradiction...).

Field Summary

protected java.util.BitSet	explanation Set of all the constraint in the explain.
protected PalmProblem	pb The current problem.
protected int	timeStamp

Constructor Summary

GenericExplanation(AbstractProblem pb)
Initializes the explain set.

Method Summary

void	add(Propagator constraint) Adds a new constraint in the explain.
void	addAll(java.util.Collection collection) Adds several constraints at a time
void	addDependencies() Updates dependencies.
void	clear() Deletes all indirect constraints.
boolean	contains(Propagator constraint) Checks if the explain contains a constraint.
boolean	containsAll(ConstraintCollection expl) Checks if another explain is included in this one.
ConstraintCollection	copy() Clones the explain as a new one.
void	delete(Propagator constraint) Deletes a constraint from the explain.
void	empties() Clears the constraint set.
java.util.BitSet	getBitSet() Copies the explain set and returns the new bitset.
Propagator	getConstraint(int i) return the i-th constraint of the explanation
SymbolicDecision[]	getNogood() return the nogood associated to the explanation
int	hashCode()
boolean	isEmpty() Checks if the explain is empty (that is wether the size of the set is null).
boolean	isValid() Checks if the explain is valid, that is wether all the constraint are active.
boolean	isValid(int time) Checks if the explain is valid, that is wether all the constraint are active.
RealBoundExplanation	makeDecSupExplanation(double sup, PalmRealVar var) Makes a DecSupExplanation from the current explain by adding dependencies.
IBoundExplanation	makeDecSupExplanation(int sup, PalmIntVar var) Makes a DecSupExplanation from the current explain by adding dependencies.
RealBoundExplanation	makeIncInfExplanation(double inf, PalmRealVar var) Makes an IncInfExplanation from the current explain by adding dependencies.
IBoundExplanation	makeIncInfExplanation(int inf, PalmIntVar var) Makes an IncInfExplanation from the current explain by adding dependencies.
IRemovalExplanation	makeRemovalExplanation(int value, PalmIntVar var) Makes a RemovalExplanation from the current explain by adding dependencies.
void	merge(ConstraintCollection explanation) Merges an explain in the current one.
void	postUndoRemoval(Constraint constraint) Posts a restoration prop.
static void	reinitTimestamp()
void	removeDependencies(Constraint removed) Removes all dependencies except for one constraint.
int	size() Get the size of the bitSet
java.util.Set	toNogood()
java.util.Set	toSet() Creates a set with all the constraints in the explain.
java.lang.String	toString() Pretty print of the explain.

Methods inherited from class java.lang.Object

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

Field Detail

timeStamp

protected int timeStamp

explanation

protected java.util.BitSet explanation

Set of all the constraint in the explain.

pb

protected PalmProblem pb

The current problem.

Constructor Detail

GenericExplanation

public GenericExplanation(AbstractProblem pb)

Initializes the explain set.

Method Detail

reinitTimestamp

public static void reinitTimestamp()

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Pretty print of the explain.

Overrides:

toString in class java.lang.Object

add

public void add(Propagator constraint)

Adds a new constraint in the explain.

Specified by:

add in interface ConstraintCollection

Parameters:

constraint - The constraint that should be added to the explain. It must be a PalmConstraint.

delete

public void delete(Propagator constraint)

Deletes a constraint from the explain.

Specified by:

delete in interface ConstraintCollection

Parameters:

constraint - The constraint that must be removed.

addAll

public void addAll(java.util.Collection collection)

Description copied from interface: ConstraintCollection

Adds several constraints at a time

Specified by:

addAll in interface ConstraintCollection

Parameters:

collection - The set of constraints

merge

public void merge(ConstraintCollection explanation)

Merges an explain in the current one.

Specified by:

merge in interface ConstraintCollection

Parameters:

explanation - The explain with the constraints to add.

isEmpty

public boolean isEmpty()

Checks if the explain is empty (that is wether the size of the set is null).

Specified by:

isEmpty in interface ConstraintCollection

size

public int size()

Get the size of the bitSet

Specified by:

size in interface ConstraintCollection

Returns:

the size of the explanation

empties

public void empties()

Clears the constraint set.

Specified by:

empties in interface Explanation

toSet

public java.util.Set toSet()

Creates a set with all the constraints in the explain.

Specified by:

toSet in interface Explanation

Returns:

The explain as a set.

getBitSet

public java.util.BitSet getBitSet()

Copies the explain set and returns the new bitset.

Specified by:

getBitSet in interface PalmExplanation

Returns:

The explain as a BitSet.

contains

public boolean contains(Propagator constraint)

Checks if the explain contains a constraint.

Specified by:

contains in interface ConstraintCollection

Parameters:

constraint - The constraint to search.

copy

public ConstraintCollection copy()

Clones the explain as a new one.

Specified by:

copy in interface ConstraintCollection

isValid

public boolean isValid()

Checks if the explain is valid, that is wether all the constraint are active.

Specified by:

isValid in interface PalmExplanation

isValid

public boolean isValid(int time)

Description copied from interface: PalmExplanation

Checks if the explain is valid, that is wether all the constraint are active. Moreover, it checks that all constraints were poseted before the specified date.

Specified by:

isValid in interface PalmExplanation

containsAll

public boolean containsAll(ConstraintCollection expl)

Checks if another explain is included in this one.

Specified by:

containsAll in interface ConstraintCollection

Parameters:

expl - The explain that is tested to be included.

clear

public void clear()

Deletes all indirect constraints.

Specified by:

clear in interface ConstraintCollection

addDependencies

public void addDependencies()

Updates dependencies.

removeDependencies

public void removeDependencies(Constraint removed)

Removes all dependencies except for one constraint.

Parameters:

removed -

makeIncInfExplanation

public IBoundExplanation makeIncInfExplanation(int inf,
                                               PalmIntVar var)

Makes an IncInfExplanation from the current explain by adding dependencies.

Specified by:

makeIncInfExplanation in interface PalmExplanation

Parameters:

inf - The previous value of the bound.

var - The involved variable.

makeDecSupExplanation

public IBoundExplanation makeDecSupExplanation(int sup,
                                               PalmIntVar var)

Makes a DecSupExplanation from the current explain by adding dependencies.

Specified by:

makeDecSupExplanation in interface PalmExplanation

Parameters:

sup - The previous value of the bound.

var - The involved variable.

makeRemovalExplanation

public IRemovalExplanation makeRemovalExplanation(int value,
                                                  PalmIntVar var)

Makes a RemovalExplanation from the current explain by adding dependencies.

Specified by:

makeRemovalExplanation in interface PalmExplanation

Parameters:

value - The removed value of the domain.

var - The involved variable.

makeIncInfExplanation

public RealBoundExplanation makeIncInfExplanation(double inf,
                                                  PalmRealVar var)

Makes an IncInfExplanation from the current explain by adding dependencies.

Specified by:

makeIncInfExplanation in interface PalmExplanation

Parameters:

inf - The previous value of the bound.

var - The involved variable.

makeDecSupExplanation

public RealBoundExplanation makeDecSupExplanation(double sup,
                                                  PalmRealVar var)

Makes a DecSupExplanation from the current explain by adding dependencies.

Specified by:

makeDecSupExplanation in interface PalmExplanation

Parameters:

sup - The previous value of the bound.

var - The involved variable.

postUndoRemoval

public void postUndoRemoval(Constraint constraint)

Posts a restoration prop.

Specified by:

postUndoRemoval in interface PalmExplanation

Parameters:

constraint -

toNogood

public java.util.Set toNogood()

getConstraint

public Propagator getConstraint(int i)

Description copied from interface: Explanation

return the i-th constraint of the explanation

Specified by:

getConstraint in interface Explanation

Parameters:

i - : the number of the constraint to return

getNogood

public SymbolicDecision[] getNogood()

Description copied from interface: Explanation

return the nogood associated to the explanation

Specified by:

getNogood in interface Explanation