omnics
Class Backtracking

java.lang.Object
  omnics.AbstractSolver
      omnics.SystematicSolver
          omnics.Backtracking

All Implemented Interfaces:

java.io.Serializable, Solver

public class Backtracking
extends SystematicSolver

A concrete implementation of SystematicSolver which uses a backtracking algorithm to explore the search space.

Author:

Cristian Frasinaru

See Also:

Serialized Form

Field Summary

Fields inherited from class omnics.SystematicSolver

assignmentStrategy, attempts, backtrackCounter, backwardStrategy, boundAlgorithm, candidates, candidatesMap, constraintsMap, DEBUG, domainsMap, eventHandler, explainer, failed, failures, filters, firingEvents, forwardStrategy, listeners, longestBacktrack, path, solutionMap, thrashing

Fields inherited from class omnics.AbstractSolver

analyzer, endTime, optimum, paused, problem, running, solution, solutions, solutionsLimit, startTime, timeLimit

Fields inherited from interface omnics.Solver

BENCHMARK_FORMAT, DETAILED_FORMAT

Constructor Summary

Backtracking(Problem problem)
Creates a new instance of BackTracking

Method Summary

void	backTo(Var var) Goes back to a specified variable
int	filterAndPropagate(Var trigger) Applies filters and propagates changes.
void	forwardTo(Var var) Moves forward
void	instantiate(Var var, java.lang.Object val)
void	revoke(Var var) Revokes an instantiation done by the solver.
TupleSet	solveAll() Solves the problem and returns all solutions or null if no solution can be found

Methods inherited from class omnics.SystematicSolver

addFilter, addListener, assign, attempts, candidates, copyCandidates, copyConstraints, copyDomain, copySolution, current, explain, explain, explain, failures, getAssignmentStrategy, getBackwardStrategy, getBoundAlgorithm, getEventHandler, getExplainer, getFailed, getFilter, getFilters, getForwardStrategy, getListeners, initSolution, isApplyingFilters, isDynamicConstrained, isFiringEvents, isPaused, last, longestBacktrack, path, printResult, printResult, removeAllFilters, removeFilter, removeListener, resolveSingletons, restoreCandidates, restoreConstraints, restoreDomain, restoreProblem, restoreSolution, setApplyingFilters, setAssignmentStrategy, setBackwardStrategy, setBoundAlgorithm, setDynamicConstrained, setEventHandler, setExplainer, setFailed, setFiringEvents, setForwardStrategy, setListeners, setPaused, stop

Methods inherited from class omnics.AbstractSolver

eval, getAnalyzer, getEndTime, getProblem, getSolutionsLimit, getStartTime, getTimeLimit, isRunning, logResult, optimum, save, setAnalyzer, setEndTime, setProblem, setRunning, setSolutionsLimit, setStartTime, setTimeLimit, solution, solutions, solve, solve, time, timeToString

Methods inherited from class java.lang.Object

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

Constructor Detail

Backtracking

public Backtracking(Problem problem)

Creates a new instance of BackTracking

Method Detail

solveAll

public final TupleSet solveAll()

Description copied from interface: Solver

Solves the problem and returns all solutions or null if no solution can be found

Specified by:

solveAll in interface Solver

Specified by:

solveAll in class AbstractSolver

Returns:

all solutions of the problem or null if the problem is inconsistent

forwardTo

public final void forwardTo(Var var)

Moves forward

instantiate

public final void instantiate(Var var,
                              java.lang.Object val)

backTo

public final void backTo(Var var)

Goes back to a specified variable

revoke

public final void revoke(Var var)

Revokes an instantiation done by the solver.

filterAndPropagate

public final int filterAndPropagate(Var trigger)

Applies filters and propagates changes.