org.drools.planner.core.termination
Interface Termination

All Superinterfaces:

EventListener, SolverLifecycleListener, SolverPhaseLifecycleListener

All Known Implementing Classes:

AbstractCompositeTermination, AbstractTermination, AndCompositeTermination, BasicPlumbingTermination, OrCompositeTermination, PhaseToSolverTerminationBridge, ScoreAttainedTermination, StepCountTermination, TimeMillisSpendTermination, UnimprovedStepCountTermination

public interface Termination
extends SolverLifecycleListener, SolverPhaseLifecycleListener

A Termination determines when a Solver or a SolverPhase should stop.

Method Summary

double	calculatePhaseTimeGradient(AbstractSolverPhaseScope solverPhaseScope) See calculateSolverTimeGradient(DefaultSolverScope).
double	calculateSolverTimeGradient(DefaultSolverScope solverScope) A timeGradient is a relative estimate of how long the search will continue.
boolean	isPhaseTerminated(AbstractSolverPhaseScope solverPhaseScope) Called by the SolverPhase after every step 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.

Methods inherited from interface org.drools.planner.core.solver.event.SolverLifecycleListener

solvingEnded, solvingStarted

Methods inherited from interface org.drools.planner.core.phase.event.SolverPhaseLifecycleListener

beforeDeciding, phaseEnded, phaseStarted, stepDecided, stepTaken

Method Detail

isSolverTerminated

boolean isSolverTerminated(DefaultSolverScope solverScope)

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

boolean isPhaseTerminated(AbstractSolverPhaseScope solverPhaseScope)

Called by the SolverPhase after every step to determine if the search should stop.

Parameters:

solverPhaseScope - never null

Returns:

true if the search should terminate.

calculateSolverTimeGradient

double calculateSolverTimeGradient(DefaultSolverScope solverScope)

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

double calculatePhaseTimeGradient(AbstractSolverPhaseScope solverPhaseScope)

See calculateSolverTimeGradient(DefaultSolverScope).

Parameters:

solverPhaseScope - 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.