Package ai.timefold.solver.core.impl.move.streams.generic.move

Class ListAssignMove<Solution_,Entity_,Value_>

java.lang.Object

ai.timefold.solver.core.impl.move.streams.generic.move.AbstractMove<Solution_>

ai.timefold.solver.core.impl.move.streams.generic.move.ListAssignMove<Solution_,Entity_,Value_>

All Implemented Interfaces:

Move<Solution_>

public final class ListAssignMove<Solution_,Entity_,Value_>
extends AbstractMove<Solution_>

Constructor Summary

Constructors

Constructor	Description
ListAssignMove(PlanningListVariableMetaModel<Solution_,Entity_,Value_> variableMetaModel, Value_ planningValue, Entity_ destinationEntity, int destinationIndex)

Method Summary

Modifier and Type	Method	Description
void	execute(@NonNull MutableSolutionView<Solution_> mutableSolutionView)	Runs the move and optionally records the changes done, so that they can be undone later.
@NonNull Collection<?>	extractPlanningEntities()	Returns all planning entities that this move is changing.
@NonNull Collection<?>	extractPlanningValues()	Returns all planning values that this move is assigning to entity variables.
protected List<VariableMetaModel<Solution_,?,?>>	getVariableMetaModels()
@NonNull Move<Solution_>	rebase(@NonNull Rebaser rebaser)	Rebases a move from an origin ScoreDirector to another destination ScoreDirector which is usually on another Thread.
@NonNull String	toString()	The solver will make sure to only call this when the move is actually printed out during debug logging.

Methods inherited from class ai.timefold.solver.core.impl.move.streams.generic.move.AbstractMove

describe, getVariableDescriptor, getVariableDescriptor, getVariableDescriptor, rebaseList, rebaseSet

Methods inherited from class java.lang.Object

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

Constructor Details

ListAssignMove

public ListAssignMove(PlanningListVariableMetaModel<Solution_,Entity_,Value_> variableMetaModel,
 Value_ planningValue,
 Entity_ destinationEntity,
 int destinationIndex)

Method Details

execute

public void execute(@NonNull MutableSolutionView<Solution_> mutableSolutionView)

Description copied from interface: Move

Runs the move and optionally records the changes done, so that they can be undone later.

Parameters:

mutableSolutionView - Exposes all possible mutative operations on the variables. Remembers those mutative operations and can replay them in reverse order when the solver needs to undo the move. Do not store this parameter in a field.

rebase

public @NonNull Move<Solution_> rebase(@NonNull Rebaser rebaser)

Description copied from interface: Move

Rebases a move from an origin ScoreDirector to another destination ScoreDirector which is usually on another Thread. It is necessary for multithreaded solving to function.

The new move returned by this method translates the entities and problem facts to the destination PlanningSolution of the destination ScoreDirector, That destination PlanningSolution is a deep planning clone (or an even deeper clone) of the origin PlanningSolution that this move has been generated from.

That new move does the exact same change as this move, resulting in the same PlanningSolution state, presuming that destination PlanningSolution was in the same state as the original PlanningSolution to begin with.

An implementation of this method typically iterates through every entity and fact instance in this move, translates each one to the destination ScoreDirector with Rebaser.rebase(Object) and creates a new move instance of the same move type, using those translated instances.

The destination PlanningSolution can be in a different state than the original PlanningSolution. So, rebasing can only depend on the identity of planning entities and problem facts, which are usually declared by a PlanningId on those classes. It must not depend on the state of the planning variables. One thread might rebase a move before, amid or after another thread does that same move instance.

This method is thread-safe.

Parameters:

rebaser - Do not store this parameter in a field

Returns:

New move that does the same change as this move on another solution instance

extractPlanningEntities

public @NonNull Collection<?> extractPlanningEntities()

Description copied from interface: Move

Returns all planning entities that this move is changing. Required for entity tabu.

This method is only called after Move.execute(MutableSolutionView), which might affect the return values.

Duplicate entries in the returned Collection are best avoided. The returned Collection is recommended to be in a stable order. For example, use List or LinkedHashSet, but not HashSet.

Returns:

Each entity only once.

extractPlanningValues

public @NonNull Collection<?> extractPlanningValues()

Description copied from interface: Move

Returns all planning values that this move is assigning to entity variables. Required for value tabu.

This method is only called after Move.execute(MutableSolutionView), which might affect the return values.

Duplicate entries in the returned Collection are best avoided. The returned Collection is recommended to be in a stable order. For example, use List or LinkedHashSet, but not HashSet.

Returns:

Each value only once.

getVariableMetaModels

protected List<VariableMetaModel<Solution_,?,?>> getVariableMetaModels()

Overrides:

getVariableMetaModels in class AbstractMove<Solution_>

toString

public @NonNull String toString()

Description copied from interface: Move

The solver will make sure to only call this when the move is actually printed out during debug logging.

Specified by:

toString in interface Move<Solution_>

Specified by:

toString in class AbstractMove<Solution_>

Returns:

A description of the move, ideally including the state of the planning entities being changed.