org.optaplanner.core.impl.solver

Class BasicPlumbingTermination

java.lang.Object

org.optaplanner.core.impl.solver.event.SolverLifecycleListenerAdapter<Solution_>

org.optaplanner.core.impl.phase.event.PhaseLifecycleListenerAdapter

org.optaplanner.core.impl.solver.termination.AbstractTermination

org.optaplanner.core.impl.solver.BasicPlumbingTermination

All Implemented Interfaces:

EventListener, PhaseLifecycleListener, SolverLifecycleListener, Termination

public class BasicPlumbingTermination
extends AbstractTermination

Concurrency notes: Condition predicate on (problemFactChangeQueue is not empty or terminatedEarly is true).

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	daemon
protected BlockingQueue<ProblemFactChange>	problemFactChangeQueue
protected boolean	problemFactChangesBeingProcessed
protected boolean	terminatedEarly

Fields inherited from class org.optaplanner.core.impl.solver.termination.AbstractTermination

logger

Constructor Summary

Constructors

Constructor and Description
BasicPlumbingTermination(boolean daemon)

Method Summary

Modifier and Type	Method and Description
boolean	addProblemFactChange(ProblemFactChange problemFactChange) Concurrency note: unblocks waitForRestartSolverDecision().
double	calculatePhaseTimeGradient(AbstractPhaseScope phaseScope) See Termination.calculateSolverTimeGradient(DefaultSolverScope).
double	calculateSolverTimeGradient(DefaultSolverScope solverScope) A timeGradient is a relative estimate of how long the search will continue.
void	endProblemFactChangesProcessing()
boolean	isEveryProblemFactChangeProcessed()
boolean	isPhaseTerminated(AbstractPhaseScope phaseScope) Called by the Phase after every step and every move to determine if the search should stop.
boolean	isSolverTerminated(DefaultSolverScope solverScope) Called by the Solver after every phase to determine if the search should stop.
boolean	isTerminateEarly()
void	resetTerminateEarly()
BlockingQueue<ProblemFactChange>	startProblemFactChangesProcessing()
boolean	terminateEarly() Concurrency note: unblocks waitForRestartSolverDecision().
boolean	waitForRestartSolverDecision() If this returns true, then the problemFactChangeQueue is definitely not empty.

Methods inherited from class org.optaplanner.core.impl.phase.event.PhaseLifecycleListenerAdapter

phaseEnded, phaseStarted, stepEnded, stepStarted

Methods inherited from class org.optaplanner.core.impl.solver.event.SolverLifecycleListenerAdapter

solvingEnded, solvingStarted

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.optaplanner.core.impl.phase.event.PhaseLifecycleListener

phaseEnded, phaseStarted, stepEnded, stepStarted

Methods inherited from interface org.optaplanner.core.impl.solver.event.SolverLifecycleListener

solvingEnded, solvingStarted

Field Detail

daemon

protected final boolean daemon

terminatedEarly

protected boolean terminatedEarly

problemFactChangeQueue

protected BlockingQueue<ProblemFactChange> problemFactChangeQueue

problemFactChangesBeingProcessed

protected boolean problemFactChangesBeingProcessed

Constructor Detail

BasicPlumbingTermination

public BasicPlumbingTermination(boolean daemon)

Method Detail

resetTerminateEarly

public void resetTerminateEarly()

terminateEarly

public boolean terminateEarly()

Concurrency note: unblocks waitForRestartSolverDecision().

Returns:

true if successful

isTerminateEarly

public boolean isTerminateEarly()

waitForRestartSolverDecision

public boolean waitForRestartSolverDecision()

If this returns true, then the problemFactChangeQueue is definitely not empty.

Concurrency note: Blocks until problemFactChangeQueue is not empty or terminatedEarly is true.

Returns:

true if the solver needs to be restarted

addProblemFactChange

public boolean addProblemFactChange(ProblemFactChange problemFactChange)

Concurrency note: unblocks waitForRestartSolverDecision().

Parameters:

problemFactChange - never null

Returns:

as specified by Collection.add(E)

startProblemFactChangesProcessing

public BlockingQueue<ProblemFactChange> startProblemFactChangesProcessing()

endProblemFactChangesProcessing

public void endProblemFactChangesProcessing()

isEveryProblemFactChangeProcessed

public boolean isEveryProblemFactChangeProcessed()

isSolverTerminated

public boolean isSolverTerminated(DefaultSolverScope solverScope)

Description copied from interface: Termination

Called by the Solver after every phase to determine if the search should stop.

Parameters:

solverScope - never null

Returns:

true if the search should terminate.

isPhaseTerminated

public boolean isPhaseTerminated(AbstractPhaseScope phaseScope)

Description copied from interface: Termination

Called by the Phase after every step and every move to determine if the search should stop.

Parameters:

phaseScope - never null

Returns:

true if the search should terminate.

calculateSolverTimeGradient

public double calculateSolverTimeGradient(DefaultSolverScope solverScope)

Description copied from interface: Termination

A timeGradient is a relative estimate of how long the search will continue.

Clients that use a timeGradient should cache it at the start of a single step because some implementations are not time-stable.

If a timeGradient can not be calculated, it should return -1.0. Several implementations (such a SimulatedAnnealingAcceptor) require a correctly implemented timeGradient.

A Termination's timeGradient can be requested after they are terminated, so implementations should be careful not to return a timeGradient above 1.0.

Parameters:

solverScope - never null

Returns:

timeGradient t for which 0.0 <= t <= 1.0 or -1.0 when it is not supported. At the start of a solver t is 0.0 and at the end t would be 1.0.

calculatePhaseTimeGradient

public double calculatePhaseTimeGradient(AbstractPhaseScope phaseScope)

Description copied from interface: Termination

See Termination.calculateSolverTimeGradient(DefaultSolverScope).

Parameters:

phaseScope - never null

Returns:

timeGradient t for which 0.0 <= t <= 1.0 or -1.0 when it is not supported. At the start of a phase t is 0.0 and at the end t would be 1.0.