org.optaplanner.core.api.solver
Interface Solver

All Known Implementing Classes:

DefaultSolver

public interface Solver

A Solver solves a planning problem. Clients usually call solve(Solution) and then getBestSolution().

These methods are not thread-safe and should be called from the same thread, except for the methods that are explicitly marked as thread-safe. Note that despite that solve(Solution) is not thread-safe for clients of this class, that method is free to do multi-threading inside itself.

Build by a SolverFactory.

Method Summary

void	addEventListener(SolverEventListener eventListener)
boolean	addProblemFactChange(ProblemFactChange problemFactChange) Schedules a ProblemFactChange to be processed.
Solution	getBestSolution()
ScoreDirectorFactory	getScoreDirectorFactory()
long	getTimeMillisSpent()
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	removeEventListener(SolverEventListener eventListener)
void	solve(Solution planningProblem) Solves the planning problem.
boolean	terminateEarly() Notifies the solver that it should stop at its earliest convenience.

Method Detail

getBestSolution

Solution getBestSolution()

Returns:

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

getTimeMillisSpent

long getTimeMillisSpent()

Returns:

the amount of millis spent between when this solver started and ended

solve

void solve(Solution planningProblem)

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

Parameters:

planningProblem - never null, usually its planning variables are uninitialized

See Also:

terminateEarly()

isSolving

boolean isSolving()

This method is thread-safe.

Returns:

true if the solve(Solution) method is still running.

terminateEarly

boolean terminateEarly()

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

This method is thread-safe.

Returns:

true if successful

See Also:

isTerminateEarly(), Future.cancel(boolean)

isTerminateEarly

boolean isTerminateEarly()

This method is thread-safe.

Returns:

true if terminateEarly has been called since the started.

See Also:

Future.isCancelled()

addProblemFactChange

boolean addProblemFactChange(ProblemFactChange problemFactChange)

Schedules a ProblemFactChange to be processed.

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

isEveryProblemFactChangeProcessed

boolean isEveryProblemFactChangeProcessed()

Checks if all scheduled ProblemFactChanges have been processed.

This method is thread-safe.

Returns:

true if there are no ProblemFactChanges left to do

addEventListener

void addEventListener(SolverEventListener eventListener)

Parameters:

eventListener - never null

removeEventListener

void removeEventListener(SolverEventListener eventListener)

Parameters:

eventListener - never null

getScoreDirectorFactory

ScoreDirectorFactory getScoreDirectorFactory()

Returns:

never null