Module org.chocosolver
Package org.chocosolver.solver.search.loop.move

Class MoveBinaryDFS

  • All Implemented Interfaces:
    Move
    Direct Known Subclasses:
    MoveBinaryHBFS, MoveBinaryLDS
    public class MoveBinaryDFS
extends Object
implements Move
    A move dedicated to run a Depth First Search with binary decisions.

    Created by cprudhom on 02/09/15. Project: choco.

    Since:
    3.3.1
    Author:
    Charles Prud'homme

    • Field Detail

      • strategy

        protected AbstractStrategy strategy
        Search strategy to extend the search tree

      • topDecisionPosition

        protected int topDecisionPosition
        Index, in the decision path, of the decision taken just before selecting this move.

    • Constructor Detail

      • MoveBinaryDFS

        public MoveBinaryDFS()
        Create this move without any search strategy

      • MoveBinaryDFS

        public MoveBinaryDFS​(AbstractStrategy strategy)
        Create this move with a search strategy
        Parameters:
        strategy - a search strategy

    • Method Detail

      • init

        public boolean init()
        Description copied from interface: Move
        Called before the search starts. Also initializes the search strategy.
        Specified by:
        init in interface Move
        Returns:
        false if something goes wrong, true otherwise

      • extend

        public boolean extend​(Solver solver)
        Description copied from interface: Move
        Performs a move when the CSP associated to the current node of the search space is not proven to be not consistent.
        Specified by:
        extend in interface Move
        Parameters:
        solver - reference the solver
        Returns:
        true if an extension can be done, false when no more extension is possible.

      • repair

        public boolean repair​(Solver solver)
        Description copied from interface: Move
        Performs a move when the CSP associated to the current node of the search space is proven to be not consistent.
        Specified by:
        repair in interface Move
        Parameters:
        solver - reference the solver
        Returns:
        true if a reparation can be done, false when no more reparation is possible.

      • setTopDecisionPosition

        public void setTopDecisionPosition​(int position)
        Description copied from interface: Move
        Indicates the position of decision made just before selecting this move. When only one "terminal" move is declared, the top decision decision is -1. When dealing with a sequence of Move, the position is the one of the last decision of the previous move. In consequence, when backtracking, the right move can be applied or stopped when needed. This has to be declared on the first call to Move.extend(Solver) and is checked on Move.repair(Solver).
        Specified by:
        setTopDecisionPosition in interface Move
        Parameters:
        position - position of the last decision taken before applying this move

      • getStrategy

        public <V extends Variable> AbstractStrategy<V> getStrategy()
        Description copied from interface: Move
        Returns the search strategy in use.
        Specified by:
        getStrategy in interface Move
        Type Parameters:
        V - the type of variable managed by the strategy
        Returns:
        the current search strategy

      • setStrategy

        public <V extends Variable> void setStrategy​(AbstractStrategy<V> aStrategy)
        Description copied from interface: Move
        Defines a search strategy, that is, a service which computes and returns decisions.
        Specified by:
        setStrategy in interface Move
        Type Parameters:
        V - the type of variable managed by the strategy
        Parameters:
        aStrategy - a search strategy

      • removeStrategy

        public void removeStrategy()
        Description copied from interface: Move
        Erases the defined search strategy.
        Specified by:
        removeStrategy in interface Move

      • rewind

        protected boolean rewind​(Solver solver)
        Go back in the search tree. Either refute a decision, or backtrack.
        Parameters:
        solver - reference to the solver
        Returns:
        true if a reparation has been found

      • prevDecision

        protected void prevDecision​(Solver solver)
        Backtrack in the search tree
        Parameters:
        solver - reference to the solver

      • getChildMoves

        public List<Move> getChildMoves()
        Description copied from interface: Move
        Returns the child moves or null Some Move only accepts one single move as child.
        Specified by:
        getChildMoves in interface Move
        Returns:
        the child moves

      • setChildMoves

        public void setChildMoves​(List<Move> someMoves)
        Description copied from interface: Move
        Overrides this child moves (if possible and if any). Some Move only accepts one single move as child.
        Specified by:
        setChildMoves in interface Move
        Parameters:
        someMoves - a new child move