org.optaplanner.core.impl.solver

Class DefaultSolver<Solution_>

java.lang.Object

org.optaplanner.core.impl.solver.AbstractSolver<Solution_>

org.optaplanner.core.impl.solver.DefaultSolver<Solution_>

Type Parameters:

Solution_ - the solution type, the class with the PlanningSolution annotation

All Implemented Interfaces:

Solver<Solution_>

public class DefaultSolver<Solution_>
extends AbstractSolver<Solution_>

Default implementation for Solver.

See Also:

Solver, AbstractSolver

Field Summary

Fields

Modifier and Type	Field and Description
protected BasicPlumbingTermination	basicPlumbingTermination
protected EnvironmentMode	environmentMode
protected org.slf4j.Logger	logger
protected RandomFactory	randomFactory
protected DefaultSolverScope<Solution_>	solverScope
protected AtomicBoolean	solving

Fields inherited from class org.optaplanner.core.impl.solver.AbstractSolver

bestSolutionRecaller, phaseLifecycleSupport, phaseList, solverEventSupport, termination

Constructor Summary

Constructors

Constructor and Description
DefaultSolver(EnvironmentMode environmentMode, RandomFactory randomFactory, BestSolutionRecaller<Solution_> bestSolutionRecaller, BasicPlumbingTermination basicPlumbingTermination, Termination termination, List<Phase<Solution_>> phaseList, DefaultSolverScope<Solution_> solverScope)

Method Summary

Modifier and Type	Method and Description
boolean	addProblemFactChange(ProblemFactChange<Solution_> problemFactChange) Schedules a ProblemFactChange to be processed.
boolean	addProblemFactChanges(List<ProblemFactChange<Solution_>> problemFactChangeList) Schedules multiple ProblemFactChanges to be processed.
String	explainBestScore() Returns a diagnostic text that explains the Solver.getBestSolution() through the ConstraintMatch API to identify which constraints or planning entities cause that Solver.getBestScore() quality.
Score	getBestScore() Returns the Score of the Solver.getBestSolution().
Solution_	getBestSolution() The best solution is the best solution found during solving: it might or might not be optimal, feasible or even initialized.
BestSolutionRecaller<Solution_>	getBestSolutionRecaller()
EnvironmentMode	getEnvironmentMode()
List<Phase<Solution_>>	getPhaseList()
RandomFactory	getRandomFactory()
InnerScoreDirectorFactory<Solution_>	getScoreDirectorFactory() Useful to reuse the Score calculation in a UI (or even to explain the Score in a UI).
DefaultSolverScope<Solution_>	getSolverScope()
long	getTimeMillisSpent() Returns the amount of milliseconds spent solving since the last start.
boolean	isEveryProblemFactChangeProcessed() Checks if all scheduled ProblemFactChanges have been processed.
boolean	isSolving() This method is thread-safe.
boolean	isTerminateEarly() This method is thread-safe.
void	outerSolvingEnded(DefaultSolverScope<Solution_> solverScope)
void	outerSolvingStarted(DefaultSolverScope<Solution_> solverScope)
Solution_	solve(Solution_ problem) Solves the planning problem and returns the best solution encountered (which might or might not be optimal, feasible or even initialized).
void	solvingEnded(DefaultSolverScope<Solution_> solverScope)
void	solvingStarted(DefaultSolverScope<Solution_> solverScope)
boolean	terminateEarly() Notifies the solver that it should stop at its earliest convenience.

Methods inherited from class org.optaplanner.core.impl.solver.AbstractSolver

addEventListener, addPhaseLifecycleListener, removeEventListener, removePhaseLifecycleListener, runPhases

Methods inherited from class java.lang.Object

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

Field Detail

logger

protected final transient org.slf4j.Logger logger

environmentMode

protected EnvironmentMode environmentMode

randomFactory

protected RandomFactory randomFactory

basicPlumbingTermination

protected BasicPlumbingTermination basicPlumbingTermination

solving

protected final AtomicBoolean solving

solverScope

protected final DefaultSolverScope<Solution_> solverScope

Constructor Detail

DefaultSolver

public DefaultSolver(EnvironmentMode environmentMode,
                     RandomFactory randomFactory,
                     BestSolutionRecaller<Solution_> bestSolutionRecaller,
                     BasicPlumbingTermination basicPlumbingTermination,
                     Termination termination,
                     List<Phase<Solution_>> phaseList,
                     DefaultSolverScope<Solution_> solverScope)

Method Detail

getEnvironmentMode

public EnvironmentMode getEnvironmentMode()

getRandomFactory

public RandomFactory getRandomFactory()

getScoreDirectorFactory

public InnerScoreDirectorFactory<Solution_> getScoreDirectorFactory()

Description copied from interface: Solver

Useful to reuse the Score calculation in a UI (or even to explain the Score in a UI).

Returns:

never null

getBestSolutionRecaller

public BestSolutionRecaller<Solution_> getBestSolutionRecaller()

getPhaseList

public List<Phase<Solution_>> getPhaseList()

getSolverScope

public DefaultSolverScope<Solution_> getSolverScope()

getBestSolution

public Solution_ getBestSolution()

Description copied from interface: Solver

The best solution is the best solution found during solving: it might or might not be optimal, feasible or even initialized.

The Solver.solve(Solution_) method also returns the best solution, but this method is useful in rare asynchronous situations (although SolverEventListener.bestSolutionChanged(BestSolutionChangedEvent) is often more appropriate).

This method is thread-safe.

Returns:

never null, but it can return the uninitialized PlanningSolution with a Score null.

getBestScore

public Score getBestScore()

Description copied from interface: Solver

Returns the Score of the Solver.getBestSolution().

This is useful for generic code, which doesn't know the type of the PlanningSolution to retrieve the Score from the Solver.getBestSolution() easily.

This method is thread-safe.

Returns:

null if the PlanningSolution is still uninitialized

explainBestScore

public String explainBestScore()

Description copied from interface: Solver

Returns a diagnostic text that explains the Solver.getBestSolution() through the ConstraintMatch API to identify which constraints or planning entities cause that Solver.getBestScore() quality. In case of an infeasible solution, this can help diagnose the cause of that.

Do not parse this string. Instead, to provide this information in a UI or a service, use Solver.getScoreDirectorFactory() to retrieve ScoreDirector.getConstraintMatchTotals() and ScoreDirector.getIndictmentMap() and convert those into a domain specific API.

This method is thread-safe.

Returns:

null if Solver.getBestScore() returns null

See Also:

ScoreDirector.explainScore()

getTimeMillisSpent

public long getTimeMillisSpent()

Description copied from interface: Solver

Returns the amount of milliseconds spent solving since the last start. If it hasn't started it yet, it returns 0. If it hasn't ended yet, it returns the time between the last start and now. If it has ended already, it returns the time between the last start and the ending.

A Solver.addProblemFactChange(ProblemFactChange) triggers a restart which resets this time.

This method is thread-safe.

Returns:

the amount of milliseconds spent solving since the last (re)start, at least 0

isSolving

public boolean isSolving()

Description copied from interface: Solver

This method is thread-safe.

Returns:

true if the Solver.solve(Solution_) method is still running.

terminateEarly

public boolean terminateEarly()

Description copied from interface: Solver

Notifies the solver that it should stop at its earliest convenience. This method returns immediately, but it takes an undetermined time for the Solver.solve(Solution_) to actually return.

This method is thread-safe.

Returns:

true if successful

See Also:

Solver.isTerminateEarly(), Future.cancel(boolean)

isTerminateEarly

public boolean isTerminateEarly()

Description copied from interface: Solver

This method is thread-safe.

Returns:

true if terminateEarly has been called since the Solver started.

See Also:

Future.isCancelled()

addProblemFactChange

public boolean addProblemFactChange(ProblemFactChange<Solution_> problemFactChange)

Description copied from interface: Solver

Schedules a ProblemFactChange to be processed.

As a side-effect, this restarts the Solver, effectively resetting all Terminations, but not Solver.terminateEarly().

This method is thread-safe. Follows specifications of BlockingQueue.add(Object) with by default a capacity of Integer.MAX_VALUE.

Parameters:

problemFactChange - never null

Returns:

true (as specified by Collection.add(E))

See Also:

Solver.addProblemFactChanges(List)

addProblemFactChanges

public boolean addProblemFactChanges(List<ProblemFactChange<Solution_>> problemFactChangeList)

Description copied from interface: Solver

Schedules multiple ProblemFactChanges to be processed.

As a side-effect, this restarts the Solver, effectively resetting all Terminations, but not Solver.terminateEarly().

This method is thread-safe. Follows specifications of Collection.addAll(Collection) with by default a capacity of Integer.MAX_VALUE.

Parameters:

problemFactChangeList - never null

Returns:

true (as specified by Collection.add(E))

See Also:

Solver.addProblemFactChange(ProblemFactChange)

isEveryProblemFactChangeProcessed

public boolean isEveryProblemFactChangeProcessed()

Description copied from interface: Solver

Checks if all scheduled ProblemFactChanges have been processed.

This method is thread-safe.

Returns:

true if there are no ProblemFactChanges left to do

solve

public final Solution_ solve(Solution_ problem)

Description copied from interface: Solver

Solves the planning problem and returns the best solution encountered (which might or might not be optimal, feasible or even initialized).

It can take seconds, minutes, even hours or days before this method returns, depending on the Termination configuration. To terminate a Solver early, call Solver.terminateEarly().

Parameters:

problem - never null, usually its planning variables are uninitialized

Returns:

never null, but it can return the original, uninitialized PlanningSolution with a Score null.

See Also:

Solver.terminateEarly()

outerSolvingStarted

public void outerSolvingStarted(DefaultSolverScope<Solution_> solverScope)

solvingStarted

public void solvingStarted(DefaultSolverScope<Solution_> solverScope)

Overrides:

solvingStarted in class AbstractSolver<Solution_>

solvingEnded

public void solvingEnded(DefaultSolverScope<Solution_> solverScope)

Overrides:

solvingEnded in class AbstractSolver<Solution_>

outerSolvingEnded

public void outerSolvingEnded(DefaultSolverScope<Solution_> solverScope)