/**
* Copyright (c) 1999-2014, Ecole des Mines de Nantes
* All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the Ecole des Mines de Nantes nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package solver.propagation.hardcoded;
import solver.Configuration;
import solver.ICause;
import solver.constraints.Constraint;
import solver.constraints.Propagator;
import solver.exception.ContradictionException;
import solver.exception.SolverException;
import solver.propagation.IPropagationEngine;
import solver.variables.Variable;
import solver.variables.events.IEventType;
import solver.variables.events.PropagatorEventType;
/**
* An fake propagation engine for debugging uses only.
* <br/>
*
* @author Charles Prud'homme
* @since 21/02/13
*/
class FakeEngine implements IPropagationEngine {
private static FakeEngine singleton = new FakeEngine();
@Override
public boolean isInitialized() {
return false;
}
@Override
public void propagate() throws ContradictionException {
}
@Override
public void flush() {
}
@Override
public void fails(ICause cause, Variable variable, String message) throws ContradictionException {
throw new SolverException("The Propagator " + cause + " is not idempotent!\n" +
"See stack trace for more details -- it can be due to a view!");
}
@Override
public ContradictionException getContradictionException() {
return null;
}
@Override
public void clear() {
}
@Override
public void onVariableUpdate(Variable variable, IEventType type, ICause cause) throws ContradictionException {
throw new SolverException("The Propagator " + cause + " is not idempotent!");
}
@Override
public void delayedPropagation(Propagator propagator, PropagatorEventType type) throws ContradictionException {
}
@Override
public void onPropagatorExecution(Propagator propagator) {
}
@Override
public void desactivatePropagator(Propagator propagator) {
}
@Override
public void dynamicAddition(Constraint c, boolean permanent) {
}
@Override
public void dynamicDeletion(Constraint c) {
}
public static void checkIdempotency(Propagator lastProp) throws ContradictionException {
if (Configuration.PRINT_PROPAGATION) {
IPropagationEngine.Trace.printPropagation(null, lastProp);
}
switch (Configuration.IDEMPOTENCY) {
case force:
if (lastProp.isActive()) {
lastProp.propagate(PropagatorEventType.FULL_PROPAGATION.getMask());
}
break;
case error:
IPropagationEngine engine = lastProp.getSolver().getEngine();
lastProp.getSolver().set(singleton);
if (lastProp.isActive()) {
lastProp.propagate(PropagatorEventType.FULL_PROPAGATION.getMask());
}
lastProp.getSolver().set(engine);
break;
}
}
}