Module org.chocosolver

Package org.chocosolver.solver.search.strategy.strategy

Class AbstractStrategy<V extends Variable>

java.lang.Object

org.chocosolver.solver.search.strategy.strategy.AbstractStrategy<V>

Direct Known Subclasses:

ActivityBased, BoundSearch, ConflictOrderingSearch, DomOverWDeg, FindAndProve, GreedyBranching, ImpactBased, IntStrategy, LastConflict, ObjectiveStrategy, RealStrategy, SetStrategy, StrategiesSequencer

public abstract class AbstractStrategy<V extends Variable>
extends Object

A search strategy provides decisions to go down in the search space. The main method is computeDecision(Variable) which returns the next decision to apply.

Since:

1 juil. 2010

Author:

Charles Prud'homme

Field Summary

Fields

Modifier and Type	Field	Description
protected V[]	vars

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractStrategy(V... variables)

Method Summary

Modifier and Type	Method	Description
protected Decision<V>	computeDecision(V var)	Computes a decision to be applied to variable var This method should be implemented in order to use search patterns
abstract Decision<V>	getDecision()	Provides access to the current decision in the strategy.
V[]	getVariables()
boolean	init()	Prepare this to be used in a search loop The initialization can detect inconsistency, in that case, it returns false
protected IntDecision	makeIntDecision(IntVar var, int val)	Creates an assignment decision object for integer variables Just a simple shortcut for : solver.getDecisionPath().makeIntDecision(var,DecisionOperatorFactory.makeIntEq(),val);
void	remove()	Remove the current strategy.
String	toString()	Creates a String object containing a pretty print of the current variables.

Methods inherited from class java.lang.Object

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

Field Detail

vars

protected final V extends Variable[] vars

Constructor Detail

AbstractStrategy

@SafeVarargs
protected AbstractStrategy(V... variables)

Method Detail

init

public boolean init()

Prepare this to be used in a search loop The initialization can detect inconsistency, in that case, it returns false

remove

public void remove()

Remove the current strategy. This implies unplugging variable or search monitors.

getDecision

public abstract Decision<V> getDecision()

Provides access to the current decision in the strategy. If there are no more decision to provide, it returns null.

Returns:

the current decision

toString

public String toString()

Creates a String object containing a pretty print of the current variables.

Overrides:

toString in class Object

Returns:

a String object

computeDecision

protected Decision<V> computeDecision(V var)

Computes a decision to be applied to variable var This method should be implemented in order to use search patterns

Parameters:

var - a variable

Returns:

a decision to be applied to variable var

getVariables

public V[] getVariables()

Returns:

array of variables

makeIntDecision

protected final IntDecision makeIntDecision(IntVar var,
                                            int val)

Creates an assignment decision object for integer variables Just a simple shortcut for : solver.getDecisionPath().makeIntDecision(var,DecisionOperatorFactory.makeIntEq(),val);

Parameters:

var - variable to branch on

val - value to branch on

Returns:

an assignment decision object (var = val) for integer variables