/**
* Check if a {@linkplain TRSPTwoOptMove 2-opt move} is feasible for the given <code>tour</code>
*
* @param tour the base tour
* @param move the {@link TRSPTwoOptMove} to be tested
* @return <code>true</code> if applying <code>move</code> to the given <code>tour</code> will
* result in a feasible tour
*/
@Override
public boolean isTwoOptFeasible(ITRSPTour itour, TRSPTwoOptMove move) {
if (!TRSPTour.class.isAssignableFrom(itour.getClass())) {
TRSPLogging.getOptimizationLogger()
.warn(
String.format(
"ToolsConstraint.isTwoOptFeasible: unsupported tour class (%s)",
itour.getClass()));
return true;
}
TRSPTour tour = (TRSPTour) itour;
if (!tour.isMainDepotVisited() // The main depot is not visited, the tour is already feasible
|| tour.isMainDepotVisited(
tour.getSucc(move.getFirst())) // The visit to the main depot is done before
// the first
// affected node
|| !tour.isMainDepotVisited(move.getSecond())) // The visit to the main depot is done
// after the last affected node
return true;
// The main depot is visited between j and m
TRSPTourIterator it = tour.iterator(move.getSecond());
// Start with node m and iterate backward
int node = it.previous();
while (node != tour.getMainDepotId() && it.hasNext()) {
if (!tour.getInstance().hasRequiredTools(tour.getTechnician().getID(), node))
// The technician does not have the required tools for this request
return false;
}
// No incompatible request was found, the move is feasible
return true;
}
/**
* Check an insertion move feasibility
*
* @param tour
* @param move
* @return 1 if move is feasible, -1 if the technician does not have the required tools and no
* visit to main depot is planned, -2 if the required tools are not available at this point
*/
private int checkInsFeasibility(ITRSPTour itour, InsertionMove move) {
if (!TRSPTour.class.isAssignableFrom(itour.getClass())) {
TRSPLogging.getOptimizationLogger()
.warn(
String.format(
"ToolsConstraint.checkInsFeasibility: unsupported tour class (%s)",
itour.getClass()));
return 1;
}
TRSPTour tour = (TRSPTour) itour;
InsertionMove m = move;
if (m.isDepotTrip() || !tour.getInstance().isRequest(move.getNodeId())) return 1;
if (!tour.isMainDepotVisited()
&& !m.isDepotTrip()
&& !tour.getInstance().hasRequiredTools(tour.getTechnician().getID(), m.getNodeId()))
return -1;
int pred = m.getInsertionPred();
if (pred == ITRSPTour.UNDEFINED) {
if (tour.getInstance().hasRequiredTools(tour.getTechnician().getID(), m.getNodeId()))
return 1;
else return -2;
} else {
for (int tool : itour.getInstance().getRequest(m.getNodeId()).getToolSet())
if (!tour.isToolAvailable(pred, tool)) return -2;
}
return 1;
}
/**
* Check if a {@linkplain TRSPShiftMove shift move} is feasible for the given <code>solution
* </code>
*
* @param solution the base solution
* @param move the {@link TRSPShiftMove} to be tested
* @return <code>true</code> if applying <code>move</code> to the given <code>solution</code> will
* result in a feasible mSolution
*/
@Override
public boolean isShiftFeasible(ITRSPTour itour, TRSPShiftMove move) {
if (!TRSPTour.class.isAssignableFrom(itour.getClass())) {
TRSPLogging.getOptimizationLogger()
.warn(
String.format(
"ToolsConstraint.isShiftFeasible: unsupported tour class (%s)",
itour.getClass()));
return true;
}
TRSPTour tour = (TRSPTour) itour;
if (!tour.isMainDepotVisited()) {
// The main depot is not visited, we assume that the tour is and will remain feasible
return true;
} else {
// The main depot is visited
if (move.getNode() == tour.getMainDepotId()) {
// The shifted node is the main depot
if (!move.isForward()) {
// A backward move of the main depot is always feasible
return true;
} else {
// Check if the requests between the current depot position and its new one require a
// visit to
// the depot to be served
List<Integer> seq = move.getChangedSequence();
for (int s : seq) {
if (s == tour.getMainDepotId())
// The requests after the main depot will be feasible
return true;
else if (!tour.getInstance().hasRequiredTools(tour.getTechnician().getID(), s))
// This request will be before the depot visit but the technician does not have the
// required
// skills
return false;
}
throw new IllegalStateException(
"Illegal state when checking the feasibility of move " + move);
}
} else {
if (tour.getInstance().hasRequiredTools(tour.getTechnician().getID(), move.getNode()))
// The technician already has the tools to serve the shifted node, the move is feasible in
// all cases
return true;
int pred =
move.getNewSucc() != ITRSPTour.UNDEFINED
? tour.getPred(move.getNewSucc())
: tour.getLastNode();
if (tour.isMainDepotVisited(move.getNode()) == tour.isMainDepotVisited(pred)) {
// Both the shifted node and its new predecessor are on the same "side" of the tour
// (either before
// or after the depot visit), the move is therefore feasible
return true;
} else {
// The shifted node and its new predecessor are on different "side" of the tour (one is
// before
// while the other is after the depot visit)
if (move.isForward()) {
// The node will be after the depot visit, the move is therefore feasible
return true;
} else {
// The node is shifted before the depot visit, while the technician does not have the
// required
// tools (tested before)
return false;
}
}
}
}
}