com.exigen.ie.constrainer.Constrainer Maven / Gradle / Ivy
package com.exigen.ie.constrainer;
///////////////////////////////////////////////////////////////////////////////
/*
* Copyright Exigen Group 1998, 1999, 2000
* 320 Amboy Ave., Metuchen, NJ, 08840, USA, www.exigengroup.com
*
* The copyright to the computer program(s) herein
* is the property of Exigen Group, USA. All rights reserved.
* The program(s) may be used and/or copied only with
* the written permission of Exigen Group
* or in accordance with the terms and conditions
* stipulated in the agreement/contract under which
* the program(s) have been supplied.
*/
///////////////////////////////////////////////////////////////////////////////
import java.io.PrintStream;
import java.io.Serializable;
import com.exigen.ie.constrainer.impl.ConstraintAllDiff;
import com.exigen.ie.constrainer.impl.ExpressionFactoryImpl;
import com.exigen.ie.constrainer.impl.FloatVarImpl;
import com.exigen.ie.constrainer.impl.FloatVarImplTrace;
import com.exigen.ie.constrainer.impl.GoalStack;
import com.exigen.ie.constrainer.impl.IntBoolVarImpl;
import com.exigen.ie.constrainer.impl.IntExpCardIntExp;
import com.exigen.ie.constrainer.impl.IntSetVarImpl;
import com.exigen.ie.constrainer.impl.IntVarImpl;
import com.exigen.ie.constrainer.impl.IntVarImplTrace;
import com.exigen.ie.constrainer.impl.UndoFastVectorAdd;
import com.exigen.ie.constrainer.impl.UndoStack;
import com.exigen.ie.constrainer.impl.UndoableFloatImpl;
import com.exigen.ie.constrainer.impl.UndoableIntImpl;
import com.exigen.ie.constrainer.impl.UndoableOnceImpl;
import com.exigen.ie.tools.FastQueue;
import com.exigen.ie.tools.FastStack;
import com.exigen.ie.tools.FastVector;
import com.exigen.ie.tools.RTExceptionWrapper;
/**
* An implementation of the Constrainer - a placeholder for all variables,
* constraints, and search goals of the problem.
*
* The Constrainer is a Java package for modeling and solving different
* constraint satisfaction problems.
*
* A problem is represented in terms of the decision variables and constraints,
* which define relationships between these variables.
*
* The decision variables could be represented in form of Java objects which may
* use the predefined constrained variables such as IntVar.
*
* The constraints themselves are objects inherited from a generic class
* Constraint.
*
* A user can define new business constraints.
*
*
* To find the problem solutions, the search algorithms could be represented
* using objects called Goals as building blocks. The Constrainer supports a
* reversible environment with multiple choice points: when constraints/goals
* fail, the Constrainer automatically backtracks to a previous choice point (if
* any).
*
* There are several basic entities in the Constrainer:
*
* - Class Constrainer - a placeholder for all variables, constraints, and
* search goals of the problem
*
- Interface Subject - a base-class for constrained variables. Contains the
* major methods to allow constraints (observers) observe the modification of
* the variables (subjects).
*
- Interface IntVar - constrained integer variables, the most popular
* subclass of the class Subject
*
- Interface Goal - a base class for different search goals and
* constraints.
*
*
* @see Goal
* @see IntVar
* @see FloatVar
* @see Subject
* @author (C)2000 Exigen Group (http://www.IntelEngine.com)
*/
/*
* Implementation notes
*
* GOALS EXECUTION. There are two major stacks: execution stack "EXE" and
* alternative stack "ALT". At each choice point we create a new reversibility
* stack "REV". EXE.push(goal); while(!EXE.empty()) { execute(EXE.pop()); Goal
* execution could: - push new subgoal on EXE (GoalAnd) - push goals on ALT
* (GoalOr) - fail. When failed: - pop from EXE all goals pushed on it after the
* last choice point (done via marker) - if ALT.empty, FAILURE! -
* EXE.push(ALT.pop()) } SUCCESS!
*
*/
public final class Constrainer implements Serializable {
static public final double FLOAT_MAX = 1.79769313486231570815e+308; // IEEE
// 754
static public final double FLOAT_MIN = 2.225073858507202e-308; // the
// smallest
// positive
// IEEE 754
static public final int INT_MAX = 2147483647;
static public final int INT_MIN = -2147483647 - 1;
static public double FLOAT_PRECISION = 1.0e-6;
// PRIVATE MEMBERS
private String _name;
private int _labelsCounter;
private FastVector _intvars;
private FastVector _floatvars;
private FastVector _intsetvars;
private FastVector _constraints;
// private FastVector _goals;
private int _choice_point = 0;
// private FastStack _execution_stack;
// private FastStack _alternative_stack;
private GoalStack _goal_stack;
// private FastStack _reversibility_stack;
private UndoStack _reversibility_stack;
private int _number_of_choice_points = 0;
private int _number_of_failures = 0;
private int _number_of_undos = 0;
private long _time_limit = 0; // in milliseconds (0-no limit)
private int _max_number_of_solutions = 0;
private boolean _time_limit_exceeded = false; // == Changed: added by OR
private long _failures_limit = 0; // in failures (0-no limit)
static private double _precision = 1e-6;
private FastVector _choice_point_objects;
// private Failure _failure;
private FastVector _failure_objects;
private boolean _trace_failure_stack;
private int _failure_display_frequency;
private FastVector _backtrack_objects;
// private Goal _goal_CP_marker;
// private Undo _undo_CP_marker;
// private Goal _restore_goal;
// private Goal _save_goal;
private boolean _trace_goals;
// private ReusableFactory _undo_subject_factory;
private boolean _show_internal_names;
private boolean _show_variable_names;
private long _initial_memory;
// private long _max_occupied_memory;
private long _number_of_notifications;
private boolean _print_information;
private long _execution_time = 0;
private FastQueue _propagation_queue;
// private FastStack _propagation_queue;
// private EventOfInterest _current_event_of_interest;
private ExpressionFactory _expressionFactory;
private FastStack _active_undoable_once;
transient private PrintStream _out = System.out;
/**
* Constructs a new constrainer - the object that serves as a placeholder
* for all other constrained objects, constraints, and goals. Each problem
* should define at least one Constrainer object. All other objects relate
* to this object.
*
* @param s
* Constrainer's symbolic name
*/
public Constrainer(String s) {
// Debug.print("Constrainer "+s);
_initial_memory = Runtime.getRuntime().totalMemory()
- Runtime.getRuntime().freeMemory();
// _max_occupied_memory = _initial_memory;
_name = new String(s);
_active_undoable_once = new FastStack();
_intvars = new FastVector();
_floatvars = new FastVector();
_intsetvars = new FastVector();
_constraints = new FastVector();
// _goals = new FastVector();
// _execution_stack = new FastStack();
// _alternative_stack = new FastStack();
// _reversibility_stack = new FastStack();
_reversibility_stack = new UndoStack();
_goal_stack = new GoalStack(_reversibility_stack);
_propagation_queue = new FastQueue();
// _goal_CP_marker = new GoalDisplay(this, "ChoicePointMarker");
// _undo_CP_marker = new UndoImpl();
// _save_goal = new GoalDisplay(this,"Save");
// _restore_goal = new GoalAnd(new GoalDisplay(this, "\nRestore!"),
// new GoalFail(this));
_show_internal_names = false;
_show_variable_names = true;
_choice_point = 0;
_number_of_choice_points = 0;
_number_of_failures = 0;
_number_of_notifications = 0;
_failure_display_frequency = 0;
_number_of_undos = 0;
_choice_point_objects = new FastVector();
_failure_objects = new FastVector();
_backtrack_objects = new FastVector();
_trace_goals = false;
_time_limit = 0;
_time_limit_exceeded = false;
// _failure = new Failure();
_trace_failure_stack = false;
_print_information = false;
// _undo_subject_factory = new UndoSubjectFactory();
_expressionFactory = new ExpressionFactoryImpl(this);
}
/*
* ==============================================================================
* High-level Components
* ============================================================================
*/
/**
* Returns the expression factory for this constrainer.
*/
public ExpressionFactory expressionFactory() {
return _expressionFactory;
}
/*
* ReusableFactory undoSubjectFactory() { return _undo_subject_factory; }
*/
/*
* ==============================================================================
* EOF High-level Components
* ============================================================================
*/
/*
* ==============================================================================
* Constraints
* ============================================================================
*/
/**
* Adds a constraint to the Constrainer. Note: the constraint added by this
* function should be posted afterwards by {@link #postConstraints()}
*
* @param ct
* The constraint to be added to the constrainer.
*
* @return The constraint passed as the parameter {@link Constraint}.
*/
public Constraint addConstraint(Constraint ct) {
_constraints.addElement(ct);
addUndo(UndoFastVectorAdd.getUndo(_constraints));
return ct;
}
/**
* Adds a constraint to the Constrainer.
*
* Constraint is given in the form of boolean expression. Note: the
* constraint added by this function should be posted afterwards by
* {@link #postConstraints()}
*
* @param ctExp
* The IntBoolExp to be added to the constrainer as a constraint.
*
* @return The constraint made from the parameter {@link Constraint}.
*/
public Constraint addConstraint(IntBoolExp ctExp) {
return addConstraint(ctExp.asConstraint());
}
/**
* Returns a vector with all currently available constraints.
*
* @return Vector of added constraints.
*/
public FastVector constraints() {
return _constraints;
}
/**
* Activates the passed constraint. This method executes the specified
* constraint.The constraint is not added to internal constraint storage
* (with which {@link #addConstraint(Constraint)} and
* {@link #postConstraints()} operates) instead it is just activated
* immediately.
*
* @param ct
* The constraint to be posted/executed.
* @throws Failure
* When the constraint can not be posted that is the constraint
* is incompatible with the previously activated ones.
*/
public void postConstraint(Constraint ct) throws Failure {
boolean ok = execute(ct);
if (!ok) {
String s = "Posting of constraint failed: " + ct;
throw new Failure(s);
}
// return ok;
}
/**
* Activates the passed constraint. This method executes the specified
* constraint provided in the form of boolean expression. The constraint is
* not added to internal constraint storage (with which
* {@link #addConstraint(Constraint)} and {@link #postConstraints()}
* operates) instead it is just activated immediately.
*
* @param ct
* The constraint to post/execute.
* @throws Failure
* When the constraint cannot be posted that is the constraint
* is incompatible with the previously activated ones.
*/
public void postConstraint(IntBoolExp ct) throws Failure {
postConstraint(ct.asConstraint());
}
/**
* Activates all the added with {@link #addConstraint(Constraint)} and not
* activated constraints.
*
* @throws Failure
* When the constraints added with
* {@link #addConstraint(Constraint)} are incompatible with the
* previously activated ones or together so they can not be
* posted.
*/
public void postConstraints() throws Failure {
postConstraints(_constraints.toArray());
}
/**
* Posts the set of constraints (or/and IntBoolExp) represented as an array
* of java.lang.Object. All constraints are being executed immediately.
*
* @param constraints
* An array of Constraints to post/execute.
* @throws Failure
* When some constraint cannot be posted (constraint is
* incompatible with others)
*/
void postConstraints(Object[] constraints) throws Failure {
Goal g = GoalPostConstraints(constraints);
if (g == null)
return;
boolean ok = execute(g);
if (!ok) {
String s;
if (constraints.length == 1)
s = "Posting of constraint failed: " + constraints[0];
else
s = "Posting of " + constraints.length + " constraints failed";
throw new Failure(s);
}
// return ok;
}
/**
* @return A goal that executes a set of constraints. Or null if there are
* no constraints to post.
*
* @param constraints
* An array of Constraints.
*/
Goal GoalPostConstraints(Object[] constraints) {
Goal g = null;
for (int i = 0; i < constraints.length; i++) {
Object o = constraints[i];
Constraint ct;
if (o instanceof Constraint) {
ct = (Constraint) o;
} else if (o instanceof IntBoolExp) {
ct = ((IntBoolExp) o).asConstraint();
} else {
throw new RuntimeException("Not a constraint: " + o);
}
if (ct == null)
continue;
if (i == 0)
g = ct;
else
g = new GoalAnd(g, ct);
}
return g;
}
/*
* ==============================================================================
* EOF Constraints
* ============================================================================
*/
/*
* ==============================================================================
* Goals
* ============================================================================
*/
// /**
// * Adds a goal to the Constrainer.
// *
// * @param goal {@link Goal} to be added to the constrainer.
// */
// public void addGoal(Goal goal)
// {
// _goals.addElement(goal);
// addUndo( UndoFastVectorAdd.getUndo(_goals) );
// }
//
// /**
// * @return All added goals.
// */
// public FastVector goals()
// {
// return _goals;
// }
/*
* ==============================================================================
* EOF Goals
* ============================================================================
*/
/*
* ==============================================================================
* Variables
* ============================================================================
*/
/**
* Adds a constrained set variable to the Constrainer
*
* @param var
* IntSetVar to be added
* @return passed variable
*/
IntSetVar addIntSetVar(IntSetVar var) {
_intsetvars.addElement(var);
addUndo(UndoFastVectorAdd.getUndo(_intsetvars));
return var;
}
/**
* Adds an internal constrained set variable to the constrainer
*
* @param var
* Variable to be added
* @return passed variable
*/
IntSetVar addIntSetVarInternal(IntSetVar var) {
_intsetvars.addElement(var);
addUndo(UndoFastVectorAdd.getUndo(_intsetvars));
return var;
}
/**
* Create new constrained set variable and adds it to the constrainer
*
* @param values
* set of possible values
* @param name
* Symbolic name of the new variable
* @return variable created based on set of possible values
*/
public IntSetVar addIntSetVar(int[] values, String name) {
IntSetVar var = new IntSetVarImpl(this, values, name);
return addIntSetVar(var);
}
/**
* Create new constrained set variable and adds it to the constrainer
*
* @param values
* set of possible values
* @return variable created based on set of possible values
*/
public IntSetVar addIntSetVar(int[] values) {
IntSetVar var = new IntSetVarImpl(this, values, "");
return addIntSetVar(var);
}
/**
* Adds a constrained integer variable to the Constrainer.
*
* @param var
* Variable to add.
* @return Passed variable.
*/
IntVar addIntVar(IntVar var) {
_intvars.addElement(var);
addUndo(UndoFastVectorAdd.getUndo(_intvars));
// addObjectToSymbolicContext(var.name(),var);
return var;
}
/**
* Adds an internal constrained integer variable to the Constrainer.
*/
IntVar addIntVarInternal(IntVar var) {
_intvars.addElement(var);
addUndo(UndoFastVectorAdd.getUndo(_intvars));
// addInternalObjectToSymbolicContext(var);
return var;
}
/**
* Adds an internal constrained integer variable to the Constrainer,
* selectively allows trace. Used in expressions that create internal
* variables for their own needs.
* Note:Constrainer's users should not use this method.
*/
public IntVar addIntVarTraceInternal(int min, int max, String name,
int type, int trace) {
IntVar var = trace != 0 ? new IntVarImplTrace(this, min, max, name,
type, trace) : new IntVarImpl(this, min, max, name, type);
return addIntVarInternal(var);
}
/**
* Adds a constrained integer variable to the Constrainer, allows trace.
*/
public IntVar addIntVarTrace(int min, int max, String name, int type,
int trace) {
IntVar var = trace != 0 ? new IntVarImplTrace(this, min, max, name,
type, trace) : new IntVarImpl(this, min, max, name, type);
return addIntVar(var);
}
/**
* Adds a constrained integer variable to the Constrainer.
*
* @param min
* The minimum possible value of the variable being added.
* @param max
* The maximum possible value of the variable being added.
* @param name
* Variable's symbolic name.
* @param type
* The {@link Domain} type of the variable being added.
* @return The added variable.
*/
public IntVar addIntVar(int min, int max, String name, int type) {
IntVar var = new IntVarImpl(this, min, max, name, type);
return addIntVar(var);
}
/**
* Adds a constrained integer variable to the Constrainer.
*
* @param min
* The minimum possible value of the variable being added.
* @param max
* The maximum possible value of the variable being added.
* @param name
* Variable's symbolic name.
* @return The added variable.
*/
public IntVar addIntVar(int min, int max, String name) {
return addIntVar(min, max, name, IntVar.DOMAIN_DEFAULT);
}
/**
* Adds a constrained integer variable to the Constrainer.
*
* @param min
* The minimum possible value of the variable being added.
* @param max
* The maximum possible value of the variable being added.
* @param type
* The {@link Domain} type of the variable being added.
*
* @return The added variable.
*/
public IntVar addIntVar(int min, int max, int type) {
return addIntVar(min, max, "", type);
}
/**
* Adds a constrained integer variable to the Constrainer.
*
* @param min
* The minimum possible value of the variable being added.
* @param max
* The maximum possible value of the variable being added.
* @return The added variable.
*/
public IntVar addIntVar(int min, int max) {
return addIntVar(min, max, "", IntVar.DOMAIN_DEFAULT);
}
/**
* Creates an constrained integer variable from the constrained integer
* expression and posts the "equals" constraint on them.
*
* @param exp
* The expression to be associated with the new variable.
* @return The added variable.
*/
public IntVar addIntVar(IntExp exp) {
// IntVar var = addIntVar(exp.min(),exp.max(),exp.name());
IntVar var = addIntVar(exp.min(), exp.max()); // no name to avoid
// duplicate name
try {
var.equals(exp).post();
} catch (Failure f) {
abort("Impossible failure in addIntVar(IntExp exp)");
}
return var;
}
/**
* Adds a constrained boolean variable to the Constrainer.
*
* @param var
* Variable to add.
* @return Added variable.
*/
IntBoolVar addIntBoolVar(IntBoolVar var) {
_intvars.add(var);
addUndo(UndoFastVectorAdd.getUndo(_intvars));
// addObjectToSymbolicContext(var.name(),var);
return var;
}
/**
* Adds an internal constrained boolean variable to the Constrainer.
*/
IntBoolVar addIntBoolVarInternal(IntBoolVar var) {
_intvars.add(var);
addUndo(UndoFastVectorAdd.getUndo(_intvars));
// addInternalObjectToSymbolicContext(var);
return var;
}
/**
* Creates and adds a constrained boolean variable to the Constrainer.
*
* @param name
* Variable's symbolic name.
*
* @return The added variable.
*/
public IntBoolVar addIntBoolVar(String name) {
IntBoolVar var = new IntBoolVarImpl(this, name);
return addIntBoolVar(var);
}
/**
* Adds an internal constrained boolean variable to the Constrainer. Used in
* expressions that create internal variables for their own needs.
* Note:Constrainer's users should not use this method.
*/
public IntBoolVar addIntBoolVarInternal(String name) {
IntBoolVar var = new IntBoolVarImpl(this, name);
return addIntBoolVarInternal(var);
}
/**
* Creates and adds a constrained boolean variable to the Constrainer.
*
* @return The added variable.
*/
public IntBoolVar addIntBoolVar() {
return addIntBoolVar("");
}
/**
* Adds a constrained floating-point variable to the Constrainer.
*
* @param var
* Variable to add.
* @return Added variable.
*/
FloatVar addFloatVar(FloatVar var) {
_floatvars.addElement(var);
addUndo(UndoFastVectorAdd.getUndo(_floatvars));
// addObjectToSymbolicContext(var.name(),var);
return var;
}
/**
* Adds an internal constrained floating-point variable to the Constrainer.
*/
FloatVar addFloatVarInternal(FloatVar var) {
_floatvars.addElement(var);
addUndo(UndoFastVectorAdd.getUndo(_floatvars));
// addInternalObjectToSymbolicContext(var);
return var;
}
/**
* Adds a constrained floating-point variable to the Constrainer, allows
* trace.
*/
public FloatVar addFloatVarTrace(double min, double max, String name,
int trace) {
FloatVar var = trace != 0 ? new FloatVarImplTrace(this, min, max, name,
trace) : new FloatVarImpl(this, min, max, name);
return addFloatVar(var);
}
/**
* Adds an internal constrained float variable to the Constrainer,
* selectively allows trace. Used in expressions that create internal
* variables for their own needs.
* Note:Constrainer's users should not use this method.
*/
public FloatVar addFloatVarTraceInternal(double min, double max,
String name, int trace) {
FloatVar var = trace != 0 ? new FloatVarImplTrace(this, min, max, name,
trace) : new FloatVarImpl(this, min, max, name);
return addFloatVarInternal(var);
}
/**
* Adds a constrained floating-point variable to the Constrainer.
*
* @param min
* The minimum possible value of the variable being added.
* @param max
* The maximum possible value of the variable being added.
* @param name
* Variable's symbolic name.
* @return The added variable.
*/
public FloatVar addFloatVar(double min, double max, String name) {
FloatVar var = new FloatVarImpl(this, min, max, name);
return addFloatVar(var);
}
/**
* Adds a constrained floating-point variable to the Constrainer.
*
* @param min
* The minimum possible value of variable being added.
* @param max
* The maximum possible value of variable being added.
* @return The added variable.
*/
public FloatVar addFloatVar(double min, double max) throws Failure {
return addFloatVar(min, max, "");
}
/**
* This method returns all integer constrained variables were ever being
* added. The set of added variables is reversible.
*
* @return All integer constrained variables.
*/
public FastVector integers() {
return _intvars;
}
/**
* Returns all float constrained variables. The set of added variables is
* reversible.
*
* @return All float constrained variables.
*/
public FastVector floats() {
return _floatvars;
}
/*
* ==============================================================================
* EOF Variables
* ============================================================================
*/
/*
* ==============================================================================
* Undoable values
* ============================================================================
*/
/**
* Adds an undoable integer to the Constrainer.
*
* @param value
* Initial value.
* @param name
* Symbolic name.
* @return Added undoable integer.
*/
public UndoableInt addUndoableInt(int value, String name) {
return new UndoableIntImpl(this, value, name);
}
/**
* Adds an undoable integer to the Constrainer.
*
* @param value
* Initial value.
* @return Added undoable integer.
*/
public UndoableInt addUndoableInt(int value) {
return new UndoableIntImpl(this, value);
}
/**
* Adds an undoable float to the Constrainer.
*
* @param value
* Initial value.
* @param name
* Symbolic name.
* @return Added undoable float.
*/
public UndoableFloat addUndoableFloat(double value, String name) {
return new UndoableFloatImpl(this, value, name);
}
/**
* Adds an undoable float to the Constrainer.
*
* @param value
* Initial value.
* @return Added undoable float.
*/
public UndoableFloat addUndoableFloat(double value) {
return new UndoableFloatImpl(this, value);
}
/*
* ==============================================================================
* EOF Undoable values
* ============================================================================
*/
/*
* ==============================================================================
* Undo objects
* ============================================================================
*/
/**
* Adds an undo-object to the reversibility stack.
*
* @param undo_object
* Undo object to add.
*/
public void addUndo(Undo undo_object) {
_number_of_undos++;
// Debug.on();Debug.print("add " + undo_object);Debug.off();
_reversibility_stack.pushUndo(undo_object);
}
/**
* Adds an undo-object to the reversibility stack for a given undoable
* object. Some undo-objects can be generated one time between choice
* points. Constrainer notifies such objects when backtrack or choice point
* occures.
*
* @param undo_object
* Undo object to add.
* @param undoable
* Undoable object to add for notification.
*/
public void addUndo(Undo undo_object, Undoable undoable) {
addUndo(undo_object);
// Adds an undoableOnce to the _active_undoable_once.
// Used in UndoableOnceImpl and allowUndos().
if (undoable instanceof UndoableOnceImpl)
_active_undoable_once.push(undoable);
}
/**
* Adds an undoable action. Undoable action is executed during backtracking.
* It has not change constrainer state (modify variables, add constraints,
* etc.). It can be used to animate search process. For example, you draw a
* square during the search and erase it in undoable action during
* backtracking.
*
* @param goal
* Undoable goal to add.
*/
public void addUndoableAction(Goal goal) {
addUndo(UndoableAction.getUndo(goal));
allowUndos(); // the action should have the state at the time when it
// was added
}
/**
* Clears the undone-flags for active undoable once objects. This force them
* to create undos again. Used: - when a choice point is set - when
* backtracking is performed
*/
void allowUndos() {
while (!_active_undoable_once.empty()) {
((UndoableOnceImpl) _active_undoable_once.pop()).restore();
}
}
/*
* ==============================================================================
* EOF Undo objects
* ============================================================================
*/
/*
* ==============================================================================
* Limits
* ============================================================================
*/
/**
* ========== Changed: limit in seconds changed to milliseconds
*
* Sets the time limit for the search execution (in milliseconds). 0 means
* no time limit (default).
*
* @param milliseconds
* The time limit to be set.
*/
public void setTimeLimit(long milliseconds) {
_time_limit = milliseconds;
}
/**
* ========== Added: an accessor for limit in seconds
*/
public long getTimeLimit() {
return _time_limit;
}
public boolean isTimeLimitExceeded() {
return _time_limit_exceeded;
}
public void setTimeLimitExceeded(boolean _time_limit_exceeded) {
this._time_limit_exceeded = _time_limit_exceeded;
}
public int getMaxNumberOfSolutions() {
return _max_number_of_solutions;
}
public void setMaxNumberOfSolutions(int max_number_of_solutions) {
_max_number_of_solutions = max_number_of_solutions;
}
public boolean isMaxNumberOfSolutionsReached(int number_of_solutions) {
if (_max_number_of_solutions <= 0)
return false;
return number_of_solutions == _max_number_of_solutions;
}
/**
* Sets the limit for the number of failures during a goal execution. 0
* means no failures limits (default).
*
* @param nf
* The number of failures to be set as the limit.
*/
public void setFailuresLimit(long nf) {
_failures_limit = nf;
}
/*
* ==============================================================================
* EOF Limits
* ============================================================================
*/
/*
* ==============================================================================
* Statistics, metrics, flags, ...
* ============================================================================
*/
/**
* This method return number of failures during search execution.
*
* @return Number of failures during execution.
*/
public int numberOfFailures() {
return _number_of_failures;
}
/**
* Sets the number of choice points. Used internally in some goals.
* Note:Constrainer's users should not use this method.
*
* @param nfs
* Number of failures.
*/
public void numberOfFailures(int nfs) {
_number_of_failures = nfs;
}
/**
* This method returns the number of choice points during search execution.
*
* @return The number of choice points during execution.
*/
public int numberOfChoicePoints() {
return _number_of_choice_points;
}
/**
* Sets the number of choice points. Used internally in some goals.
* Note:Constrainer's users should not use this method.
*
* @param cps
* Number of choice points.
*/
public void numberOfChoicePoints(int cps) {
_number_of_choice_points = cps;
}
/**
* Return the search execution time.
*
* @return The search execution time in milliseconds.
*/
public long executionTime() {
return _execution_time;
}
/**
* Used internally in the implementation of subject when it sends a
* notificaction event.
* Note:Constrainer's users should not use this method.
*/
public void incrementNumberOfNotifications() {
_number_of_notifications++;
}
/**
* This method returns the number of notifications occured during search
* execution.
*
* @return The number of notifications.
*/
public long numberOfNotifications() {
return _number_of_notifications;
}
/**
* Controls whether to show the internal names for the expressions.
*
* @param flag
* true if show.
*/
public void showInternalNames(boolean flag) {
_show_internal_names = flag;
}
/**
* Returns true if internal names for the expressions are shown.
*
* @return true if internal names for the expressions are shown.
*/
public boolean showInternalNames() {
return _show_internal_names;
}
/**
* Changes variable names printing behaviour.
*
* @param flag
* Boolean parameter. To enable printing should be set to true
* and otherwise to false.
*/
public void showVariableNames(boolean flag) {
_show_variable_names = flag;
}
/**
* Returns variable names printing behaviour flag.
*
* @return the variable names printing flag.
*/
public boolean showVariableNames() {
return _show_variable_names;
}
/**
* Enables printing the internal constrainer's information.
*/
public void printInformation() {
_print_information = true;
}
/**
* Sets the precision of the constrained floating-point variable
* calculations The default value is 1E-06.
*
* @param prc
* The new precision to be set.
*/
static public void precision(double prc) {
FLOAT_PRECISION = prc;
}
/**
* Returns the precision of the constrained floating-point variable
* calculations.
*
* @return the precision of the constrained floating-point variable
* calculations.
*/
static public double precision() {
return FLOAT_PRECISION;
}
/*
* ==============================================================================
* EOF Statistics, metrics, flags, ...
* ============================================================================
*/
/*
* ==============================================================================
* Tracing
* ============================================================================
*/
/**
* The function turns on the tracing for the subject. The expression is
* printed to {@link #out()} every time when subject send notification
* event.
* For example, when domain of the consstraint expression changed.
*
* @param subject
* the expression to be watched for modifications.
*/
public void trace(Subject subject) {
subject.trace();
}
/**
* The function turns on the tracing for the array of the constrained
* integer expressions. The array is printed to {@link #out()} every time
* when at least one variable from this vector is modified.
*
* @param vars
* the array to be watched for modifications.
*/
public void trace(IntExpArray vars) {
class ObserverTraceVars extends Observer {
private IntExpArray _vars;
ObserverTraceVars(IntExpArray vars) {
_vars = vars;
}
public void update(Subject var, EventOfInterest interest)
throws Failure {
_out.println("Trace " + interest + ": " + _vars);
}
public int subscriberMask() {
return EventOfInterest.ALL;
}
public Object master() {
return Constrainer.this;
}
} // ~ ObserverTraceVars
Observer observer = new ObserverTraceVars(vars);
for (int i = 0; i < vars.size(); i++) {
Subject var = (Subject) vars.get(i);
var.attachObserver(observer);
}
}
/**
* Performs tracing during backtracking.
*
* @param obj
* Object that is printed using toString() method.
*/
public void traceBacktracks(Object obj) {
_backtrack_objects.addElement(obj);
}
/**
* Turns on the tracing of the failures. Object is printed to {@link #out()}
* when failure occures.
*
* @param frequency
* Frequency of the tracing.
* @param obj
* Object to print.
*/
public void traceFailures(int frequency, Object obj) {
_failure_display_frequency = frequency;
if (obj != null)
_failure_objects.addElement(obj);
}
/**
* Turns on the tracing of the failures.
*
* @param frequency
* Frequency of the tracing.
*/
public void traceFailures(int frequency) {
traceFailures(frequency, null);
}
/**
* Turns on the tracing of every failure.
*/
public void traceFailures() {
traceFailures(1);
}
/**
* Tells the constrainer to display the Java stack trace when a failure
* occurs. To control the frequency of such displaying, use
* traceFailres(frequency). For example, to display the stack on failure#25,
* use: C.traceFailureStack(); C.traceFailures(25);
*/
public void traceFailureStack() {
_trace_failure_stack = true;
}
/**
* Turns on the tracing of every failure. Object is printed to
* {@link #out()} when failure occures.
*
* @param obj
* Object to print.
*/
public void traceFailures(Object obj) {
traceFailures(1, obj);
}
/**
* Returns true if failure tracing is on.
*
* @return true if failure tracing is on.
*/
public boolean showFailures() {
return (_failure_display_frequency > 0);
}
/**
* Turn on tracing of the goal execution.
*/
public void traceExecution() {
showInternalNames(true);
_trace_goals = true;
}
/**
* Turn on tracing of choice points. Object is printed to {@link #out()}
* when choice point occures.
*
* @param obj
* Object to print.
*/
public void traceChoicePoints(Object obj) {
_choice_point_objects.addElement(obj);
}
/**
* The function turns off all tracings for the Constrainer.
*/
public void traceOff() {
showInternalNames(false);
_trace_goals = false;
_backtrack_objects.clear();
_choice_point_objects.clear();
_failure_objects.clear();
_trace_failure_stack = false;
_failure_display_frequency = 0;
}
/*
* ==============================================================================
* EOF Tracing
* ============================================================================
*/
/*
* ==============================================================================
* Special expressions, constraints, ...
* ============================================================================
*/
/**
* Returns constrained set being intersection of two sets variables passed
*
* @param var1
* first constrained set variable
* @param var2
* second constrained set variable
* @return var1.intersectionWith(var2)
*/
public IntSetVar intersection(IntSetVar var1, IntSetVar var2) {
return var1.intersectionWith(var2);
}
/**
* Returns constrained set variable being union of two sets
*
* @param var1
* first constrained set variable
* @param var2
* second constrained set variable
* @return var1.unionWith(var2)
*/
public IntSetVar union(IntSetVar var1, IntSetVar var2) {
return var1.unionWith(var2);
}
/**
* Returns expression being equal to the number of required values in a set
* domain
*
* @param var
* constrained set variable
* @return var.cardinality() expression
*/
public IntExp cardinality(IntSetVar var) {
return var.cardinality();
}
/**
* States that two sets has empty intersection
*
* @param var1
* first constrained set variable
* @param var2
* second constrained set variable
* @return var1.nullIntersectionWith(var2) constraint
*/
public Constraint nullIntersect(IntSetVar var1, IntSetVar var2) {
return var1.nullIntersectWith(var2);
}
/**
* Returns expression: sum of passed expressions: var1.add(var2)
*
* @param var1
* First expression
* @param var2
* Second expression
* @return var1.add(var2) expression
*/
public IntExp sum(IntExp var1, IntExp var2) {
return var1.add(var2);
}
/**
* Returns the constrained integer expression that equals to the sum of all
* expressions from the array.
*
* @param vars
* The array of constrained integer expressions to sum.
* @return the constrained integer expression equal to the sum.
*/
public IntExp sum(IntExpArray vars) {
/*
* int min = 0; int max = 0; for(int i=0; i < vars.size(); ++i) { IntVar
* var = (IntVar)vars.elementAt(i); min += var.min(); max += var.max(); }
* IntVar result = addIntVar(min,max); execute(new
* ConstraintAddVector(vars,result)); return result;
*/
return vars.sum();
}
/**
* Returns the constrained integer expression that equals to the scalar
* product of the array of constrained integer expressions and the array of
* int values. The expression has the following symbolic form:
* exps[0]*values[0] + exps[1]*values[1] + ...
*
* @param exps
* The array of constrained integer expressions.
* @param values
* The array of int values.
* @return The scalar product constrained integer expression.
*/
public IntExp scalarProduct(IntExpArray exps, int[] values) {
int size = exps.size();
if (values.length != size)
throw new RuntimeException(
"scalarProduct parameters have different size");
IntExpArray products = new IntExpArray(this, size);
for (int i = 0; i < size; i++) {
products.set(exps.elementAt(i).mul(values[i]), i);
}
return products.sum();
}
/**
* Returns the constrained floating-point expression that equals to the
* scalar product of the array of constrained floating-point expressions and
* the array of double values. The expression has the following
* symbolic form: exps[0]*values[0] + exps[1]*values[1] + ...
*
* @param exps
* The array of constrained floating-point expressions.
* @param values
* The array of double values.
* @return The scalar product constrained floating-point expression.
*/
public FloatExp scalarProduct(FloatExpArray exps, double[] values) {
int size = exps.size();
if (values.length != size)
throw new RuntimeException(
"scalarProduct parameters have different size");
FloatExpArray products = new FloatExpArray(this, size);
for (int i = 0; i < size; i++) {
products.set(exps.elementAt(i).mul(values[i]), i);
}
return products.sum();
}
/**
* Returns the constrained floating-point expression that equals to the
* scalar product of the array of constrained integer expressions and the
* array of double values. The expression has the following symbolic
* form: exps[0]*values[0] + exps[1]*values[1] + ...
*
* @param exps
* The array of constrained integer expressions.
* @param values
* The array of double values.
* @return The scalar product constrained floating-point expression.
*/
public FloatExp scalarProduct(IntExpArray exps, double[] values) {
int size = exps.size();
if (values.length != size)
throw new RuntimeException(
"scalarProduct parameters have different size");
FloatExpArray products = new FloatExpArray(this, size);
for (int i = 0; i < size; i++) {
products.set(exps.elementAt(i).mul(values[i]), i);
}
return products.sum();
}
/**
* Returns a constrained integer expression that is equal to the number of
* variables in "vars" bound to the "value".
*
* @param intvars
* The array of constrained integer expressions.
* @param value
* The value to be checked.
* @return The constrained integer expression that is equal to the number of
* variables in "vars" bound to the "value".
* @throws Failure
*/
public IntExp cardinality(IntExpArray intvars, int value) throws Failure {
// IntVar card = addIntVar(0,intvars.size(),"Count of "+value);
// ConstraintCardinality ct = new
// ConstraintCardinality(intvars,value,card);
// ct.execute(); // may fail
// return card;
return intvars.cards().cardAt(value);
}
/**
* All elements of an array are associated with their domains. The union of
* the domains makes up the array "domain" that is the set of all values
* that may occur in the array. An instance of {@link IntArrayCards} class
* is associated with each instance of {@link IntExpArray}. The instance
* keeps track the possible number of the value occurrences in the array
* that is it has an element(constrained integer expression) per value from
* the array "domain". For each value from the array "domain" the method
* {@link #distribute(IntExpArray , IntExpArray)} creates the constraint
* "equals" to the number of occurrences of values. The number of
* occurrences for each value of array "domain" is specified in
* cards parameter.
*
* @param vars
* The array of constrained integer expressions.
* @param cards
* The array of value occurences.
* @return The array of value cardinalities.
* @throws Failure
*/
public IntArrayCards distribute(IntExpArray vars, IntExpArray cards)
throws Failure {
IntArrayCards vcards = vars.cards();
for (int i = 0; i < vcards.cardSize(); ++i) {
Constraint ct = vcards.cardAt(i).equals(cards.get(i));
ct.execute();
}
return vcards;
}
/**
* Returns an array of constrained integer variables "cards" such that
* cards[i] is equal to the number of variables in "vars" bound to the value
* values[i].
*/
/*
* public Vector distribute(Vector vars, int[] values) throws Failure {
* Vector cards = new Vector(); for(int i=0; i< values.length; ++i) {
* cards.addElement(cardinality(vars,values[i]));
* //cards.addElement(addIntVar(0,vars.size(),"Count of "+values[i])); } //
* redundant constraint IntExp card_sum = new IntExpAddVector(this, cards);
* card_sum.less(vars.size()+1).execute(); return cards; }
*/
/**
* Returns the array of constrained integer variables "cards" such that
* cards[i] is equal to the number of variables in "vars" bound to the value
* values[i].
*
* @param vars
* The array of constrained ineteger variables.
* @param values
* The array of value to be checked.
*
* @return The array of values cardinalities in vars.
* @throws Failure
*/
public IntExpArray distribute(IntExpArray vars, int[] values)
throws Failure {
IntArrayCards vcards = vars.cards();
FastVector cards = new FastVector();
for (int i = 0; i < values.length; ++i) {
cards.addElement(vcards.cardAt(values[i]));
// cards.addElement(addIntVar(0,vars.size(),"Count of "+values[i]));
}
// redundant constraint
return new IntExpArray(this, cards);
}
/**
* Returns an array of constrained integer variables "cards" such that
* cards[i] is equal to the number of variables in "vars" bound to the
* sequental [0,vars.size()] values.
*
* @param vars
* Array of variables.
* @return An array of constrained integer variables.
* @throws Failure
*/
public IntExpArray distribute(IntExpArray vars) throws Failure {
int size = vars.size();
int[] values = new int[size];
for (int i = 0; i < size; ++i) {
values[i] = i;
}
return distribute(vars, values);
}
/**
* Returns an array of n constrained integer variables "cards" such that
* cards[i] is equal to the number of variables in "vars" bound to the value
* i.
*
* @param vars
* The array of constrained ineteger expressions.
* @param n
* The value to be checked.
* @return The array of value cardinalities.
* @throws Failure
*/
public IntExpArray distribute(IntExpArray vars, int n) throws Failure {
int[] values = new int[n];
for (int i = 0; i < n; ++i) {
values[i] = i;
}
return distribute(vars, values);
}
/**
* Creates "All Different" constraint.
*
* @param intvars
* The array of constrained integer variables.
* @return Constraint stating that all variables in the specified array must
* be different.
*/
public Constraint allDiff(IntExpArray intvars) {
return new ConstraintAllDiff(intvars);
}
/*
* ==============================================================================
* EOF Special expressions, constraints, ...
* ============================================================================
*/
/*
* ==============================================================================
* Execution, backtracking, choice points
* ============================================================================
*/
/**
* Backtracks to the most recent choice point.
*/
boolean backtrack() {
return backtrack(null);
}
/**
* Backtracks to the most recent labeled choice point.
*/
boolean backtrack(ChoicePointLabel label) {
boolean success = _goal_stack.backtrack(label);
allowUndos();
if (success) {
if (_backtrack_objects.size() > 0)
printObjects(_out, "BACKTRACK: ", _backtrack_objects);
}
return success;
}
/**
* Executes the goal without state restoration.
*
* @return true if success
* @param goal
* com.exigen.ie.constrainer.Goal
*/
public boolean execute(Goal goal) {
return execute(goal, false);
}
/**
* Executes the search goal provided by the first parameter. In most cases,
* the goal is expected to find a solution: to instantiate all constrained
* objects and satisfied all constraints. Returns true if the solution is
* found. Returns false otherwise. The second parameter allows a user to
* restore the state of the constrainer after the succesful execution of the
* main_goal.
*
* @return true if success
* @param main_goal
* com.exigen.ie.constrainer.Goal
* @param restore_flag
* boolean
*/
synchronized public boolean execute(Goal main_goal, boolean restore_flag) {
long execution_start = System.currentTimeMillis();
setTimeLimitExceeded(false);
boolean success = true;
// long start_seconds = System.currentTimeMillis()/1000; == changed by OR to milliseconds
long start_milliseconds = System.currentTimeMillis();
// save current _goal_stack
GoalStack old_goal_stack = _goal_stack;
_goal_stack = new GoalStack(main_goal, _reversibility_stack);
allowUndos();
boolean timeLimitExceeded = false;
ChoicePointLabel label = null;
while (!_goal_stack.empty()) {
try {
Goal goal = _goal_stack.popGoal();
if (_trace_goals) {
_out.println("Execute: " + goal);
}
goal = goal.execute();
propagate();
if (goal != null) {
_goal_stack.pushGoal(goal);
}
} catch (Failure f) {
if (_trace_failure_stack
&& _failure_display_frequency > 0
&& _number_of_failures % _failure_display_frequency == 0) {
f.printStackTrace(_out);
}
clearPropagationQueue();
// checking out the time limit
if (_time_limit > 0) {
// long now_seconds = System.currentTimeMillis()/1000; Changed by OR
long now_milliseconds = System.currentTimeMillis();
if (now_milliseconds - start_milliseconds > _time_limit) {
String msg = "Constrainer: Time limit for solution search " + _time_limit + " mills has been exceeded";
setTimeLimitExceeded(true);
_out.println(msg);
_out.println("Number of Failures: " + numberOfFailures()); // Added by JF
success = false;
timeLimitExceeded = true;
label = f.label();
//throw new TimeLimitException(msg, f.label());
break;
}
}
// check failures limit
if (_failures_limit > 0) {
if (_number_of_failures > _failures_limit) {
_out.println("Failures Limit Violation: more than "
+ _failures_limit);
success = false;
break;
}
}
// Backtrack
if (!backtrack(f.label())) {
success = false;
break;
}
} catch (Throwable t) {
_out.println("Unexpected exception: " + t.toString());
t.printStackTrace(_out);
abort("Unexpected exception: ", t);
}
} // ~while
boolean restoreAnyway = restore_flag || !success;
if (restoreAnyway) {
_reversibility_stack.backtrack(_goal_stack.undoStackSize());
}
_execution_time += System.currentTimeMillis() - execution_start;
if (_print_information) {
if (!(main_goal instanceof Constraint))
doPrintInformation();
}
_goal_stack = old_goal_stack;
return success;
}
/**
* @param label
* @param restore_flag
*/
synchronized public boolean toContinue(ChoicePointLabel label,
boolean restore_flag) {
long execution_start = System.currentTimeMillis();
boolean success = true;
// long start_seconds = System.currentTimeMillis()/1000; === Changed by
// OR to milliseconds
long start_milliseconds = System.currentTimeMillis();
// save current _goal_stack
GoalStack old_goal_stack = _goal_stack;
// _goal_stack = new GoalStack(main_goal, _reversibility_stack);
allowUndos();
// Backtrack
if (!backtrack(label)) {
success = false;
}
if (success)
while (!_goal_stack.empty()) {
try {
Goal goal = _goal_stack.popGoal();
if (_trace_goals) {
_out.println("Execute: " + goal);
}
goal = goal.execute();
propagate();
// if (_print_information) {
// long occupied_memory = Runtime.getRuntime()
// .totalMemory()
// - Runtime.getRuntime().freeMemory();
// if (_max_occupied_memory < occupied_memory)
// _max_occupied_memory = occupied_memory;
// }
if (goal != null) {
_goal_stack.pushGoal(goal);
}
} catch (Failure f) {
if (_trace_failure_stack
&& _failure_display_frequency > 0
&& _number_of_failures % _failure_display_frequency == 0) {
f.printStackTrace(_out);
}
// if (_print_information) {
// long occupied_memory = Runtime.getRuntime()
// .totalMemory()
// - Runtime.getRuntime().freeMemory();
// if (_max_occupied_memory < occupied_memory)
// _max_occupied_memory = occupied_memory;
// }
clearPropagationQueue();
// check time limit
if (_time_limit > 0) {
// long now_seconds = System.currentTimeMillis()/1000;
// ====Changed by OR to milliseconds
long now_milliseconds = System.currentTimeMillis();
if (now_milliseconds - start_milliseconds > _time_limit) {
String msg = "Time limit for one solution search " + _time_limit + " mills has been exceeded";
_out.println(msg);
setTimeLimitExceeded(true);
success = false;
throw new TimeLimitException(msg,f.label());
//break;
}
}
// check failures limit
if (_failures_limit > 0) {
if (_number_of_failures > _failures_limit) {
_out.println("Failures Limit Violation: more than "
+ _failures_limit);
success = false;
break;
}
}
// Backtrack
if (!backtrack(f.label())) {
success = false;
break;
}
} catch (Throwable t) {
_out.println("Unexpected exception: " + t.toString());
t.printStackTrace(_out);
abort("Unexpected exception: ", t);
}
} // ~while
boolean restoreAnyway = restore_flag || !success;
if (restoreAnyway) {
_reversibility_stack.backtrack(_goal_stack.undoStackSize());
}
_execution_time += System.currentTimeMillis() - execution_start;
/*
* if (_print_information) { if(!(main_goal instanceof Constraint))
* doPrintInformation(); }
*/
_goal_stack = old_goal_stack;
return success;
}
/**
* Sets a choice point between two goals.
*/
void setChoicePoint(Goal g1, Goal g2) {
setChoicePoint(g1, g2, null);
}
/**
* Sets a labeled choice point between two goals.
*/
void setChoicePoint(Goal g1, Goal g2, ChoicePointLabel label) {
_number_of_choice_points++;
_goal_stack.setChoicePoint(g1, g2, label);
allowUndos();
if (_choice_point_objects.size() > 0)
printObjects(_out, "CP " + (_choice_point - 1) + ":",
_choice_point_objects);
}
/**
* Pushes the goal onto the goal stack.
*/
void pushOnExecutionStack(Goal goal) {
_goal_stack.pushGoal(goal);
}
/**
* generate a unique ChoicePointLabel
*
*/
public ChoicePointLabel createChoicePointLabel() {
_labelsCounter++;
return new ChoicePointLabel(this, _labelsCounter);
}
/**
* Returns the label of the current choice point.
*/
ChoicePointLabel currentChoicePointLabel() {
return _goal_stack.currentChoicePoint().label();
}
/**
* Returns a number of the last solution (total amount of available
* solutions) Checks from 0 to max_sol
*
* @param max_sol
* Maximum solution number to check.
* @return Nuber of the last solution or max_sol
*/
public int getSolutionsNumber(Goal main_goal, int max_sol) {
GoalCheckSolutionNumber check = new GoalCheckSolutionNumber(this,
max_sol);
Goal goal = new GoalAnd(main_goal, check);
if (execute(goal, true))
return max_sol;
else
return check.getCurrentSolutionNumber();
}
/**
* Executes the search goal provided by the first parameter to find a
* solution with the "solution_number".
*
* @param main_goal
* Goal to execute
* @param solution_number
* Number of desired solution
* @param restore_flag
* Restoration flag.
* @return true if success
*/
public boolean execute(Goal main_goal, int solution_number,
boolean restore_flag) {
Goal goal = new GoalAnd(main_goal, new GoalCheckSolutionNumber(this,
solution_number));
return execute(goal, restore_flag);
}
/**
* Executes the search goal provided by the first parameter to find a
* solution with the "solution_number".
*
* @param main_goal
* Goal to execute.
* @param solution_number
* Solution to find.
* @return true if success
*/
public boolean execute(Goal main_goal, int solution_number) {
return execute(main_goal, solution_number, false);
}
/**
* Executes the search goal provided by the first parameter to find all the
* problem solutions. Each solution should be saved/printed inside the
* main_goal. After the goal execution the state of the constrainer is
* restored.
*
* @param main_goal
* The goal to execute.
* @return true if the goal has been successfully executed.
*/
public boolean executeAll(Goal main_goal) {
Goal all_solutions = new GoalAllSolutions(main_goal);
return execute(all_solutions);
}
/*
* ==============================================================================
* EOF Execution, backtracking, choice points
* ============================================================================
*/
/*
* ==============================================================================
* Propagation
* ============================================================================
*/
/**
* Adds the subject (usually variable) to the propagation queue. It happenes
* when the subject changes its state. The notificatioin events will be
* generated in {@link #propagate} method.
*/
public void addToPropagationQueue(Subject subject) {
_propagation_queue.push(subject);
}
/**
* Propagate events triggered by successful goal execution.
*/
final public void propagate() throws Failure {
while (!_propagation_queue.empty()) {
Subject var = (Subject) _propagation_queue.pop();
var.inProcess(false);
var.propagate(); // may fail
// if (!var.inProcess())
// var.clearPropagationEvents();
}
}
/**
* Clears the propagation queue.
*/
void clearPropagationQueue() {
while (!_propagation_queue.empty()) {
Subject var = (Subject) _propagation_queue.pop();
var.inProcess(false);
// var.clearPropagationEvents();
}
}
/*
* ==============================================================================
* EOF Propagation
* ============================================================================
*/
/*
* ==============================================================================
* Failures
* ============================================================================
*/
/**
* Throws Failure exception.
*
* @throws Failure
*/
public void fail() throws Failure {
fail("");
}
/**
* Throws Failure exception.
*
* @param s
* The diagnostic message.
* @throws Failure
*/
public void fail(String s) throws Failure {
fail(s, null);
}
/**
* Throws Failure exception.
*
* @param s
* The diagnostic message.
* @throws Failure
*/
public void fail(String s, ChoicePointLabel label) throws Failure {
_number_of_failures++;
if (_failure_display_frequency > 0
&& _number_of_failures % _failure_display_frequency == 0) {
_out.println("Failure " + _number_of_failures + ": " + s);
}
if (_failure_display_frequency == 0
|| _number_of_failures % _failure_display_frequency == 0)
for (int i = 0; i < _failure_objects.size(); i++) {
_out.println("Failure: " + s + " "
+ _failure_objects.elementAt(i));
}
/*
* if (showInternalNames()) _failure.message(s); else
* _failure.message("");
*/
throw new Failure(s, label);// _failure; //
}
/*
* ==============================================================================
* EOF Failures
* ============================================================================
*/
/*
* ==============================================================================
* Misc: toString(), helpers, ...
* ============================================================================
*/
/**
* This method aborts the program execution. It prints the "msg" and the
* stack trace. Used to display "impossible" errors.
*
* @param msg
* Diagnostic message to print.
*/
static public void abort(String msg) {
abort(msg, new RuntimeException(msg));
}
static public void abort(String msg, Throwable t) {
throw RTExceptionWrapper.wrap(msg, t);
}
/**
* Prints the statistical information. This information is accumulated
* during the execution of the goals.
*/
void doPrintInformation() {
_out.println("\nChoice Points: " + _number_of_choice_points
+ " Failures: " + _number_of_failures + " Undos: "
+ _number_of_undos + " Notifications: "
+ _number_of_notifications
// + " Memory: " + (_max_occupied_memory - _initial_memory)
+ " Time: " + _execution_time + "msec");
}
/**
* Helper to print the vector of obects.
*
*/
static void printObjects(PrintStream out, String prefix, FastVector objects) {
int size = objects.size();
Object[] data = objects.data();
for (int i = 0; i < size; i++) {
out.print(prefix);
out.println(data[i]);
}
}
/**
* Returns the string representation of the constrainer.
*
* @return the string representation of the constrainer.
*/
public String toString() {
return "Constrainer: " + _name + "\n" + _goal_stack + "\n"
+ _reversibility_stack;
}
/**
* Returns the Constrainer's output stream where the output information is
* printed out.
*
* @return the Constrainer's output stream where the output information is
* printed out.
*/
public PrintStream out() {
return _out;
}
/**
* Sets the output stream where the information is printed.
*
* @param out
* the output stream to be set for Constrainer's output.
*/
public void out(PrintStream out) {
_out = out;
}
/*
* ==============================================================================
* EOF Misc: helpers,...
* ============================================================================
*/
/*
* ==============================================================================
* Symbolic context and expressions
* ============================================================================
*/
// /**
// * Adds an internal object to the symbolic context.
// */
// void addInternalObjectToSymbolicContext(Object o)
// {
// try
// {
// symbolicContext().addInternalVar(o);
// }
// catch(Exception e)
// {
// _out.println(e.getMessage());
// }
// }
// /**
// * Adds named object to the symbolic context.
// */
// void addObjectToSymbolicContext(String name, Object o)
// {
// try
// {
// symbolicContext().setVar(name,o);
// }
// catch(Exception e)
// {
// _out.println(e.getMessage());
// }
// }
/**
* Returns context for this constrainer.
*/
// Context constrainerContext()
// {
// Context cxt1 = new ObjectContext(getClass(),this);
// Context cxt2 = new ConstrainerContext(this);
// cxt2.setParent(cxt1);
// return cxt2;
// }
/**
* Evaluate a code written in the symbolic form.
*/
// Object evaluateSpl(String s) throws Exception
// {
// s = s + ";";
// Context cxt = constrainerContext();
// Algebra algebra = Algebra.constrainerAlgebra();
//
// SplCode code = new SplCode(s);
// code.validate(cxt,algebra);
// return code.evaluate(cxt, algebra);
// }
/**
* Evaluate a constraint written in the symbolic form.
*/
// public Constraint evaluateConstraint(String s) throws Exception
// {
// Object result = evaluateSpl(s);
//
// if(result instanceof IntBoolExp)
// {
// return ((IntBoolExp)result).asConstraint();
// }
// else if(result instanceof Constraint)
// {
// return (Constraint)result;
// }
// else
// {
// throw new Exception( "Invalid constraint."
// + " String: '" + s + "'."
// + " Result: '" + result + "'." );
// }
//
// }
/**
* Adds a constraint written in the symbolic form. Note: the constraint
* added by this function should be posted afterwards by
* {@link #postConstraints()}
*
* @param s
* The string representing constraint.
*
* @return The constraint made from the parameter {@link Constraint}.
*/
// public Constraint addConstraint(String s) throws Exception
// {
// Constraint ct = evaluateConstraint(s);
// addConstraint(ct);
// return ct;
// }
/**
* Posts a constraint written in the symbolic form. Makes passed constraint
* active. This method executes specified constraint given in the form of
* boolean expression. The constraint is not being added to internal
* constraint storage (with which {@link #addConstraint(Constraint)} and
* {@link #postConstraints()} operate, but is just being activated
* immediately.
*
* @param s
* String represented constraint.
* @throws Exception
* When some constraint cannot be posted (constraint is
* incompatible with others) or when string is invalid.
*/
// void postConstraint(String s) throws Exception
// {
// Constraint ct = evaluateConstraint(s);
// postConstraint(ct);
// }
/*
* ==============================================================================
* EOF Symbolic expressions
* ============================================================================
*/
/*
* extending to 5.1.0 added by S. Vanskov
*/
/**
* Returns a constrained integer expression that is equal to the number of
* variables in array bound to the value of
* exp .
*
* @param array The array of constrained integer expressions.
* @param exp The constrained integer expression to be checked.
*
* @return The constrained integer expression that is equal to the number
* of variables in array bound to the value of exp .
*
* @throws Failure
*/
public IntExp cardinality(IntExpArray array, IntExp exp) throws Failure {
return new IntExpCardIntExp(array, exp);
}
/* EO additions */
/**
* functions providing the possibility of supporting multi-session added by
* E. Tseitlin
*/
IntVar[] getIntVars(int[] indices) {
if (indices == null)
return null;
IntVar[] ari = new IntVar[indices.length];
Object[] vars = _intvars.data();
for (int i = 0; i < indices.length; i++) {
ari[i] = (IntVar) vars[indices[i]];
}
return ari;
}
FloatVar[] getFloatVars(int[] indices) {
if (indices == null)
return null;
FloatVar[] ari = new FloatVar[indices.length];
Object[] vars = _floatvars.data();
for (int i = 0; i < indices.length; i++) {
ari[i] = (FloatVar) vars[indices[i]];
}
return ari;
}
int[] findAppropriate(IntVar[] intVars) {
if (intVars == null)
return null;
int size = intVars.length;
int[] indices = new int[size];
java.util.HashMap map = new java.util.HashMap(size);
Object[] vars = _intvars.data();
for (int i = 0; i < vars.length; i++) {
map.put(vars[i], new Integer(i));
}
int validsCounter = 0;
for (int i = 0; i < size; i++) {
Integer idx = (Integer) (map.get(intVars[i]));
if (idx != null) {
indices[validsCounter] = idx.intValue();
validsCounter++;
}
}
int[] out = new int[validsCounter];
System.arraycopy(indices, 0, out, 0, validsCounter);
return out;
}
int[] findAppropriate(FloatVar[] floatVars) {
if (floatVars == null)
return null;
int size = floatVars.length;
int[] indices = new int[size];
java.util.HashMap map = new java.util.HashMap(size);
Object[] vars = _floatvars.data();
for (int i = 0; i < vars.length; i++) {
map.put(vars[i], new Integer(i));
}
int validsCounter = 0;
for (int i = 0; i < size; i++) {
Integer idx = (Integer) (map.get(floatVars[i]));
if (idx != null) {
indices[validsCounter] = idx.intValue();
validsCounter++;
}
}
int[] out = new int[validsCounter];
System.arraycopy(indices, 0, out, 0, validsCounter);
return out;
}
} // ~Constrainer