overhauled route search algorithm:

now using breadth-first search instead of depth-first search

pom.xml

@@ -4,7 +4,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>de.srsoftware</groupId>
 	<artifactId>web4rail</artifactId>
-	<version>1.4.6</version>
+	<version>1.4.7</version>
 	<name>Web4Rail</name>
 	<packaging>jar</packaging>
 	<description>Java Model Railway Control</description>

resources/translations/Application.de.translation

@@ -326,6 +326,7 @@ Start actions : Start-Aktionen
 Stock ID : Inventarnummer
 Stop settings : Halte-Einstellungen
 Start autopilot : Autopilot starten
+Start delay : Start-Verzögerung
 Started {} : {} gestartet
 starting delay : Anfahrverzögerung
 State : Status

src/main/java/de/srsoftware/web4rail/Range.java

@@ -13,8 +13,18 @@ public class Range extends BaseClass{
 	private static final String MAX = "max";
 	private static final String MIN = "min";
 	
-	public int min=0,max=10000;
+	public int min,max;
 	
+	public Range(int min, int max) {
+		this.min = min;
+		this.max = max;
+		validate();
+	}
+
+	public Range() {
+		this(0,10_000);
+	}
+
 	public JSONObject json() {
 		return new JSONObject(Map.of(MIN,min,MAX,max));
 	}

src/main/java/de/srsoftware/web4rail/Route.java

@@ -22,7 +22,6 @@ import de.srsoftware.web4rail.Plan.Direction;
 import de.srsoftware.web4rail.actions.Action;
 import de.srsoftware.web4rail.actions.ActionList;
 import de.srsoftware.web4rail.actions.BrakeStart;
-import de.srsoftware.web4rail.actions.DelayedAction;
 import de.srsoftware.web4rail.actions.FinishRoute;
 import de.srsoftware.web4rail.actions.PreserveRoute;
 import de.srsoftware.web4rail.actions.SetSignal;
@@ -76,6 +75,12 @@ public class Route extends BaseClass {
 
 	private static final String ROUTE_SETUP = "route_setup";
 
+	private static final String MIN_START_DELAY = "min_start_delay";
+
+	private static final String MAX_START_DELAY = "max_start_delay";
+
+	private static final String STARt_DELAY = "start_delay";
+
 	private static HashMap<Id, String> names = new HashMap<Id, String>(); // maps id to name. needed to keep names during plan.analyze()
 
 	private HashMap<String,Integer>        brakeTimes = new HashMap<String, Integer>();
@@ -85,17 +90,17 @@ public class Route extends BaseClass {
 	private boolean                        disabled = false;
 	private Block                          endBlock = null;
 	public  Direction					   endDirection;
+	private Route                          nextPreparedRoute = null;
+	private RoutePrepper                   nextRoutePrepper = null;
 	private Vector<Tile>                   path;
 	private Vector<Signal>                 signals;
 	private HashMap<String,ActionList>     triggeredActions = new HashMap<String, ActionList>();
 	private HashMap<Turnout,Turnout.State> turnouts;
 	private Block                          startBlock = null;
+	private Range                          startDelay = null;
 	public  Direction 					   startDirection;
 	private HashSet<Contact>			   triggeredContacts = new HashSet<>();
 
-	private Route nextPreparedRoute;
-
-	private RoutePrepper nextRoutePrepper;
 	
 	public Route() {
 		conditions = new ConditionList();
@@ -303,12 +308,8 @@ public class Route extends BaseClass {
 			add(ROUTE_SETUP,new SetTurnout(this).setTurnout(turnout).setState(state));
 		}
 		for (Signal signal : signals) add(ROUTE_SETUP,new SetSignal(this).set(signal).to(Signal.GREEN));
-		if (signals.isEmpty()) {
+		startDelay = signals.isEmpty() ? new Range(0,0) : new Range(1000,7500); 
-			add(ROUTE_START,new SetSpeed(this).to(999));
+		add(ROUTE_START,new SetSpeed(this).to(999));
-		} else {
-			DelayedAction da = new DelayedAction(this).setMinDelay(1000).setMaxDelay(7500);
-			add(ROUTE_START,da.add(new SetSpeed(this).to(999)));
-		}
 		return this;
 	}
 
@@ -485,6 +486,7 @@ public class Route extends BaseClass {
 		if (isSet(name)) json.put(NAME, name);
 		
 		if (disabled) json.put(DISABLED, true);
+		if (isSet(startDelay)) json.put(STARt_DELAY, startDelay.json());
 
 		return json;
 	}
@@ -618,6 +620,7 @@ public class Route extends BaseClass {
 			JSONObject dummy = json.getJSONObject(BRAKE_TIMES);
 			dummy.keySet().forEach(key -> brakeTimes.put(key, dummy.getInt(key)));
 		}
+		if (json.has(STARt_DELAY)) startDelay = new Range().load(json.getJSONObject(STARt_DELAY));
 		return plan.registerRoute(this);
 	}
 
@@ -725,7 +728,12 @@ public class Route extends BaseClass {
 		formInputs.add(t("Name"),nameSpan);
 		Checkbox checkbox = new Checkbox(DISABLED, t("disabled"), disabled);
 		if (disabled) checkbox.clazz("disabled");
-		formInputs.add(t("State"),checkbox);		
+		formInputs.add(t("State"),checkbox);
+		
+		Tag span = new Tag("span");
+		new Input(MIN_START_DELAY,isSet(startDelay) ? startDelay.min : 0).numeric().addTo(span).content(" ... ");
+		new Input(MAX_START_DELAY,isSet(startDelay) ? startDelay.max : 0).numeric().addTo(span).content(" ms");
+		formInputs.add(t("Start delay"),span);
 		
 		postForm.add(basicProperties());
 		if (!turnouts.isEmpty()) postForm.add(turnouts());
@@ -846,9 +854,10 @@ public class Route extends BaseClass {
 		if (parts.length>1) name(parts[0].trim()+" - "+parts[parts.length-1].trim());
 		return this;
 	}
-
+	
-	public boolean start() {
+	public boolean startNow() {		
-		LOG.debug("{}.start()",this);
+		LOG.debug("{}.startNow()",this);
+		
 		if (isNull(context) || context.invalidated()) {
 			LOG.debug("Invalid context: {}",context);
 			return false;
@@ -878,6 +887,11 @@ public class Route extends BaseClass {
 		return true;
 	}
 
+	public boolean start() {		
+		if (isSet(startDelay)) sleep(startDelay.random());
+		return startNow();
+	}
+
 	public Block startBlock() {
 		return startBlock;
 	}
@@ -916,11 +930,35 @@ public class Route extends BaseClass {
 		
 		disabled = "on".equals(params.get(DISABLED));
 		
+		String delay = params.get(MIN_START_DELAY);
+		if (isSet(delay)) try {
+			int min = Integer.parseInt(delay);
+			if (isNull(startDelay)) {
+				startDelay = new Range(min, min);
+			} else {
+				startDelay.min = min;
+				startDelay.validate();
+			}
+		} catch (NumberFormatException e) {}
+
+		delay = params.get(MAX_START_DELAY);
+		if (isSet(delay)) try {
+			int max = Integer.parseInt(delay);
+			if (isNull(startDelay)) {
+				startDelay = new Range(max, max);
+			} else {
+				startDelay.max = max;
+				startDelay.validate();
+			}
+		} catch (NumberFormatException e) {}
+
+		
 		Condition condition = Condition.create(params.get(REALM_CONDITION));
 		if (isSet(condition)) {
 			condition.parent(this);
 			conditions.add(condition);
 		}
+		
 		super.update(params);
 		return properties();
 	}

src/main/java/de/srsoftware/web4rail/actions/SetTurnout.java

@@ -28,7 +28,7 @@ public class SetTurnout extends Action {
 	public boolean fire(Context context,Object cause) {
 		if (context.invalidated()) return false;
 		if (isNull(turnout)) return false;		
-		if (!turnout.state(state).succeeded()) return false;
+		if (!turnout.state(state,false).succeeded()) return false;
 		if (turnout.address() == 0) return true;
 		sleep(1000);
 		return true;

src/main/java/de/srsoftware/web4rail/moving/Train.java

@@ -979,7 +979,7 @@ public class Train extends BaseClass implements Comparable<Train> {
 		autopilot |= auto;
 		if (isSet(nextPreparedRoute)) {
 			LOG.debug("starting nextPreparedRoute: {}",nextPreparedRoute);
-			if (nextPreparedRoute.start()) {
+			if (nextPreparedRoute.startNow()) {
 				LOG.debug("dropped nextPreparedRoute (was {})",nextPreparedRoute);
 				nextPreparedRoute = null;
 				return null;

src/main/java/de/srsoftware/web4rail/threads/RoutePrepper.java

@@ -1,11 +1,11 @@
 package de.srsoftware.web4rail.threads;
 
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map.Entry;
 import java.util.TreeMap;
-import java.util.Vector;
 
 import de.srsoftware.web4rail.Application;
 import de.srsoftware.web4rail.BaseClass;
@@ -17,6 +17,23 @@ import de.srsoftware.web4rail.tiles.Block;
 import de.srsoftware.web4rail.tiles.Tile;
 
 public class RoutePrepper extends BaseClass implements Runnable{
+	
+	private static class Candidate{
+
+		private int score;
+		private Route route;
+
+		public Candidate(Route r, int s) {
+			route = r;
+			score = s;
+		}
+		
+		@Override
+		public String toString() {
+			return route+"(score: "+score+")";
+		}
+	}
+	
 	private Context context;
 	private Route route;
 	private List<EventListener> failListeners = new LinkedList<>(); 
@@ -33,118 +50,113 @@ public class RoutePrepper extends BaseClass implements Runnable{
 		if (!errors.isEmpty()) throw new NullPointerException(String.join(", ", errors));
 		context = c;
 	}
-	
+		
-	private static TreeMap<Integer, List<Route>> availableRoutes(Context context, HashSet<Route> visitedRoutes) {
+	private static TreeMap<Integer,LinkedList<Route>> availableRoutes(Context c){
-		String inset = "";
-		for (int i = 0; i < visitedRoutes.size(); i++) inset += "    ";
-		LOG.debug("{}{}.availableRoutes({})", inset, RoutePrepper.class.getSimpleName(), context);
-
-		Block block = context.block();
-		Train train = context.train();
-		Direction startDirection = context.direction();
-		Route currentRoute = context.route();
-		TreeMap<Integer, List<Route>> availableRoutes = new TreeMap<Integer, List<Route>>();
-
 		boolean error = false;
-		if (isNull(block) && (error = true))
+		
-			LOG.warn("{} → {}.availableRoutes called without context.block!", inset, Train.class.getSimpleName());
+		Block startBlock = c.block();
-		if (isNull(train) && (error = true))
+		if (isNull(startBlock) && (error=true)) LOG.warn("RoutePrepper.findRoute(…) called without a startBlock!");
-			LOG.warn("{}→ {}.availableRoutes called without context.train!", inset, Train.class.getSimpleName());
+		
-		if (error) return availableRoutes;
+		Train train = c.train();
-
+		if (isNull(train) && (error=true)) LOG.warn("RoutePrepper.findRoute(…) called without a startBlock!");
-		if (isSet(startDirection)) {
+		
-			LOG.debug("{}- Looking for {}-bound routes from {}", inset, startDirection, block);
+		if (error) return new TreeMap<>();
-		} else {
-			LOG.debug("{}- Looking for all routes from {}", inset, block);
-		}
 		
 		Block destination = train.destination();
-		if (isSet(destination) && visitedRoutes.isEmpty()) LOG.debug("{}- Destination: {}", inset, destination);
+		
-
+		Direction startDirection = c.direction();
-		for (Route routeCandidate : block.leavingRoutes()) {
+		LOG.debug("RoutePrepper.findRoute({},{},{}), dest = {}",startBlock,startDirection,train,destination);
-			if (context.invalidated()) return availableRoutes;
+		
-			if (visitedRoutes.contains(routeCandidate)) {
+		TreeMap<Integer, LinkedList<Route>> candidates = routesFrom(c);
-				LOG.debug("{}→ Candidate {}  would create loop, skipping", inset, routeCandidate.shortName());
+		
-				continue;
+		if (isNull(destination)) {
-			}
+			LOG.debug("{} has no destination, returning {}",train,candidates);
-
+			return candidates;
-			HashSet<Tile> stuckTrace = train.stuckTrace(); // if train has been stopped in between two blocks lastly:
+		}
-															// only allow starting routes that do not conflict with current train
+		
-															// position
+		LOG.debug("{} is heading for {}, starting breadth-first search…",train,destination);
-			if (isSet(stuckTrace) && visitedRoutes.isEmpty() && !routeCandidate.path().containsAll(stuckTrace)) {
+		
-				LOG.debug("Stuck train occupies tiles ({}) outside of {} – not allowed.", stuckTrace, routeCandidate);
+		HashMap<Route,Candidate> predecessors = new HashMap<>();
-				continue;
+		TreeMap<Integer,LinkedList<Route>> routesToDest = new TreeMap<>();
-			}
+		
-
+		int level = 0;
-			if (!routeCandidate.allowed(context)) {
+		
-				if (routeCandidate.endBlock() != destination) { // allowance may be overridden by destination
+		while (!candidates.isEmpty()) {
-					LOG.debug("{} not allowed for {}", routeCandidate, context);
+			TreeMap<Integer, LinkedList<Route>> queue = new TreeMap<>();
-					continue; // Zug darf auf Grund einer nicht erfüllten Bedingung nicht auf die Route
+			
+			while (!candidates.isEmpty()) {
+				Candidate candidate = pop(candidates);
+				LOG.debug(" - examining {}…",candidate);
+				
+				Block endBlock = candidate.route.endBlock();
+				Direction endDir = candidate.route.endDirection;
+				
+				if (endBlock == destination) {
+					LOG.debug(" - {} reaches destination!",candidate);
+					int score = candidate.score;
+					
+					// The route we found leads to the destination block.
+					// However it might be the last route in a long path.
+					// Thus, we need to get the first route in this path:					
+					while (predecessors.containsKey(candidate.route)) { 
+						candidate = predecessors.get(candidate.route);
+						LOG.debug("   - predecessed by {}",candidate);
+						score += candidate.score;
+					}
+					
+					LOG.debug(" → path starts with {} and has total score of {}",candidate.route,score);
+					LinkedList<Route> routesForScore = routesToDest.get(score);
+					if (isNull(routesForScore)) routesToDest.put(score, routesForScore = new LinkedList<Route>());
+					routesForScore.add(candidate.route);
+					continue;
 				}
-				LOG.debug("{} not allowed for {} – overridden by selected destination", routeCandidate, context);
+				
-			}
+				LOG.debug(" - {} not reaching {}, adding ongoing routes to queue:",candidate,destination);
-
+				TreeMap<Integer, LinkedList<Route>> successors = routesFrom(c.clone().block(endBlock).direction(endDir));
-			int priority = 0;
+				while (!successors.isEmpty()) {
-			if (isSet(startDirection) && routeCandidate.startDirection != startDirection) { // Route startet entgegen
+					int score = successors.firstKey();
-																							// der aktuellen
+					LinkedList<Route> best = successors.remove(score);
-																							// Fahrtrichtung des Zuges
+					score -= 25; // Nachfolgeroute
-				if (!train.pushPull) continue; // Zug kann nicht wenden
+					for (Route route : best) {
-				if (!block.turnAllowed) continue; // Wenden im Block nicht gestattet
+						LOG.debug("   - queueing {} with score {}",route,score);
-				priority -= 5;
+						if (predecessors.containsKey(route)) continue; // Route wurde bereits besucht
-			}
+						predecessors.put(route, candidate);
-			if (routeCandidate == currentRoute) priority -= 10; // möglichst andere Route als zuvor wählen // TODO: den
+						
-																// Routen einen "last-used" Zeitstempel hinzufügen, und
+						LinkedList<Route> list = queue.get(score);
-																// diesen mit in die Priorisierung einbeziehen
+						if (isNull(list)) queue.put(score, list = new LinkedList<>());
-
+						list.add(route);
-			if (isSet(destination)) {
+					}
-				if (routeCandidate.endBlock() == destination) { // route goes directly to destination
-					LOG.debug("{}→ Candidate {} directly leads to {}", inset, routeCandidate.shortName(), destination);
-					priority = 1_000_000;
-				} else {
-					LOG.debug("{}- Candidate: {}", inset, routeCandidate.shortName());
-					Context forwardContext = new Context(train).block(routeCandidate.endBlock()).route(null)
-						.direction(routeCandidate.endDirection);
-					visitedRoutes.add(routeCandidate);
-					TreeMap<Integer, List<Route>> forwardRoutes = availableRoutes(forwardContext, visitedRoutes);
-					visitedRoutes.remove(routeCandidate);
-					if (forwardRoutes.isEmpty()) continue; // the candidate does not lead to a block, from which routes
-															// to the destination exist
-					Entry<Integer, List<Route>> entry = forwardRoutes.lastEntry();
-					LOG.debug("{}→ The following routes have connections to {}:", inset, destination);
-					for (Route rt : entry.getValue()) LOG.debug("{}  - {}", inset, rt.shortName());
-					priority += entry.getKey() - 10;
 				}
 			}
-
+			
-			List<Route> routeSet = availableRoutes.get(priority);
+			if (!routesToDest.isEmpty()) return routesToDest;
-			if (isNull(routeSet)) {
+			LOG.debug("No routes to {} found with distance {}!",destination,level);
-				routeSet = new Vector<Route>();
+			level ++;
-				availableRoutes.put(priority, routeSet);
+			candidates = queue;
-			}
-			routeSet.add(routeCandidate);
-			if (routeCandidate.endBlock() == destination) break; // direct connection to destination discovered, quit
-																	// search
-		}
-		if (!availableRoutes.isEmpty())
-			LOG.debug("{}→ Routes from {}: {}", inset, block, availableRoutes.isEmpty() ? "none" : "");
-		for (Entry<Integer, List<Route>> entry : availableRoutes.entrySet()) {
-			LOG.debug("{} - Priority {}:", inset, entry.getKey());
-			for (Route r : entry.getValue()) LOG.debug("{}    - {}", inset, r.shortName());
 		}
-		return availableRoutes;
+		LOG.debug("No more candidates for routes towards {}!",destination);
+		
+		return new TreeMap<>();
+		
 	}
 	
 	private static Route chooseRoute(Context context) {
 		LOG.debug("{}.chooseRoute({})", RoutePrepper.class.getSimpleName(), context);
-		TreeMap<Integer, List<Route>> availableRoutes = availableRoutes(context, new HashSet<Route>());
+		TreeMap<Integer, LinkedList<Route>> availableRoutes = availableRoutes(context);
+		LOG.debug("available routes: {}",availableRoutes);
 		while (!availableRoutes.isEmpty()) {
 			if (context.invalidated()) break;
 			LOG.debug("availableRoutes: {}", availableRoutes);
-			Entry<Integer, List<Route>> entry = availableRoutes.lastEntry();
+			Entry<Integer, LinkedList<Route>> entry = availableRoutes.lastEntry();
 			List<Route> preferredRoutes = entry.getValue();
 			LOG.debug("preferredRoutes: {}", preferredRoutes);
 			Route selectedRoute = preferredRoutes.get(random.nextInt(preferredRoutes.size()));
-			if (selectedRoute.isFreeFor(context)) {
+			
+			HashSet<Tile> stuckTrace = context.train().stuckTrace(); // if train has been stopped in between two blocks lastly: 
+                                                                     // only allow starting routes that do not conflict with current train position
+			if (isSet(stuckTrace) && !selectedRoute.path().containsAll(stuckTrace)) {
+				LOG.debug("Stuck train occupies tiles ({}) outside of {} – not allowed.", stuckTrace, selectedRoute);
+			} else if (selectedRoute.isFreeFor(context)) {
 				LOG.debug("Chose \"{}\" with priority {}.", selectedRoute, entry.getKey());
 				return selectedRoute;
 			}
@@ -156,6 +168,11 @@ public class RoutePrepper extends BaseClass implements Runnable{
 		return null;
 	}
 	
+	private boolean fail() {
+		notify(failListeners);
+		route = null;
+		return false;
+	}	
 	
 	private void notify(List<EventListener> listeners) {
 		for (EventListener listener: listeners) {
@@ -163,13 +180,6 @@ public class RoutePrepper extends BaseClass implements Runnable{
 		}		
 	}
 	
-	private boolean fail() {
-		notify(failListeners);
-		// if (isSet(route) route.reset();
-		route = null;
-		return false;
-	}
-	
 	public void onFail(EventListener l) {
 		failListeners.add(l);
 	}
@@ -186,7 +196,20 @@ public class RoutePrepper extends BaseClass implements Runnable{
 		preparedListener = l;
 	}
 	
-
+	private static Candidate pop(TreeMap<Integer, LinkedList<Route>> candidates) {
+		while (!candidates.isEmpty()) {
+			int score = candidates.firstKey();
+			LinkedList<Route> list = candidates.get(score);
+			if (isNull(list) || list.isEmpty()) {
+				candidates.remove(score);
+			} else {
+				Candidate candidate = new Candidate(list.removeFirst(),score);
+				if (list.isEmpty()) candidates.remove(score);
+				return candidate;
+			}
+		}
+		return null;
+	}
 	
 	public boolean prepareRoute() {
 		if (isNull(context) || context.invalidated()) return fail();
@@ -206,6 +229,53 @@ public class RoutePrepper extends BaseClass implements Runnable{
 		return route;
 	}
 
+	private static TreeMap<Integer,LinkedList<Route>> routesFrom(Context c){
+		boolean error = false;
+		
+		Block startBlock = c.block();
+		if (isNull(startBlock) && (error=true)) LOG.warn("RoutePrepper.routesFrom(…) called without a startBlock!");
+		
+		Train train = c.train();
+		if (isNull(train) && (error=true)) LOG.warn("RoutePrepper.routesFrom(…) called without a startBlock!");
+		
+		if (error) return null;
+		
+		Block destination = train.destination();
+		
+		Direction startDirection = c.direction();
+		
+		LOG.debug("RoutePrepper.routesFrom({},{},{}), dest = {}",startBlock,startDirection,train,destination);
+			
+		TreeMap<Integer, LinkedList<Route>> routes = new TreeMap<>();
+		
+		for (Route route : startBlock.leavingRoutes()) {
+			LOG.debug(" - evaluating {}",route);
+
+			int score = 0;
+			
+			if (!route.allowed(new Context(train).block(startBlock).direction(startDirection))) {
+				LOG.debug("   - {} not allowed for {}", route, train);
+				if (route.endBlock() != destination) continue;
+				LOG.debug("       …overridden by destination of train!", route, train);
+			}
+			
+			if (route.endBlock() == destination) score = 100_000;
+			
+			if (isSet(startDirection) && route.startDirection != startDirection) { // Route startet entgegen der aktuellen Fahrtrichtung des Zuges
+				if (!train.pushPull) continue; // Zug kann nicht wenden
+				if (!startBlock.turnAllowed) continue; // Wenden im Block nicht gestattet
+				score -= 5;
+			}
+			
+			LinkedList<Route> routesForScore = routes.get(score);
+			if (isNull(routesForScore)) routes.put(score, routesForScore = new LinkedList<Route>());
+			LOG.debug("   → candidate!");
+			routesForScore.add(route);
+		}
+		
+		return routes;
+	}
+	
 	@Override
 	public void run() {
 		LOG.debug("{}.run()",this);

src/main/java/de/srsoftware/web4rail/tiles/Contact.java

@@ -27,7 +27,6 @@ import de.srsoftware.web4rail.tags.Window;
 import de.srsoftware.web4rail.threads.DelayedExecution;
 
 public class Contact extends Tile{
-	private static Logger LOG = LoggerFactory.getLogger(Contact.class);
 	private static final String ADDRESS = "address";
 	private static final HashMap<Integer, Contact> contactsByAddr = new HashMap<Integer, Contact>();
 	private boolean state = false;

src/main/java/de/srsoftware/web4rail/tiles/Turnout.java

@@ -52,7 +52,7 @@ public abstract class Turnout extends Tile implements Device{
 	@Override
 	public Object click(boolean shift) throws IOException {
 		LOG.debug(getClass().getSimpleName()+".click()");
-		if (!shift) init();
+		init();
 		return super.click(shift);
 	}
 
@@ -159,9 +159,13 @@ public abstract class Turnout extends Tile implements Device{
 		return state;
 	}
 	
-	public Reply state(State newState) {
+	public Reply state(State newState,boolean shift) {
 		Train lockingTrain = lockingTrain();
-		if (isSet(lockingTrain) && newState != state) return new Reply(415, t("{} locked by {}!",this,lockingTrain));
+
+		if (isSet(lockingTrain)) {
+			if (newState != state && !shift) return new Reply(415, t("{} locked by {}!",this,lockingTrain));
+			// shift allows to switch locked turnouts...
+		} else if (shift) return new Reply(200,"OK"); // shift on a non-locked turnout skips the switch process
 		if (address == 0) { 
 			sleep(300);
 			state = newState;			

src/main/java/de/srsoftware/web4rail/tiles/TurnoutL.java

@@ -15,7 +15,7 @@ public abstract class TurnoutL extends Turnout {
 	@Override
 	public Object click(boolean shift) throws IOException {
 		Object o = super.click(shift);
-		if (!shift) state(state == State.STRAIGHT ? State.LEFT : State.STRAIGHT);
+		state(state == State.STRAIGHT ? State.LEFT : State.STRAIGHT,shift);
 		return o;
 	}
 	

src/main/java/de/srsoftware/web4rail/tiles/TurnoutR.java

@@ -15,13 +15,12 @@ public abstract class TurnoutR extends Turnout {
 	@Override
 	public Object click(boolean shift) throws IOException {
 		Object o = super.click(shift);
-		if (!shift) state(state == State.STRAIGHT ? State.RIGHT : State.STRAIGHT);
+		state(state == State.STRAIGHT ? State.RIGHT : State.STRAIGHT,shift);
 		return o;
 	}
 	
 	@Override
 	public String commandFor(State newState) {
-
 		switch (newState) {
 		case RIGHT:			
 			return "SET {} GA "+address+" "+portB+" 1 "+delay;