Checkstyle

src/edu/kit/informatik/model/Coach.java

@@ -19,6 +19,10 @@ public abstract class Coach extends RollingStock {
      * Regex pattern to match coach identifiers.
      */
     public static final Pattern IDENTIFIER_PATTERN = Pattern.compile(IDENTIFIER_PREFIX + "\\+?\\d+");
+    /**
+     * Regex pattern to match coach type (passenger, freight, or special).
+     */
+    public static final String COACH_TYPE = "passenger|freight|special";
 
     /**
      * The unique identifier of this coach.
@@ -33,8 +37,7 @@ public abstract class Coach extends RollingStock {
      * @param couplingBack whether the coach should have a back coupling
      * @throws InvalidInputException on invalid user input (zero-sized coach)
      */
-    public Coach(final int identifier, final int length,
+    public Coach(int identifier, int length, boolean couplingFront, boolean couplingBack) throws InvalidInputException {
-                 final boolean couplingFront, final boolean couplingBack) throws InvalidInputException {
         super(length, couplingFront, couplingBack);
         this.identifier = identifier;
     }

src/edu/kit/informatik/model/DieselEngine.java

@@ -30,8 +30,8 @@ public class DieselEngine extends Engine {
      * @param couplingBack whether the engine should have a back coupling
      * @throws InvalidInputException on invalid user input (e.g. zero-sized engine)
      */
-    public DieselEngine(final String series, final String name, final int length,
+    public DieselEngine(String series, String name, int length,
-                        final boolean couplingFront, final boolean couplingBack) throws InvalidInputException {
+                        boolean couplingFront, boolean couplingBack) throws InvalidInputException {
         super(series, name, length, couplingFront, couplingBack);
     }
 

src/edu/kit/informatik/model/ElectricalEngine.java

@@ -32,8 +32,8 @@ public class ElectricalEngine extends Engine {
      * @param couplingBack whether the engine should have a back coupling
      * @throws InvalidInputException on invalid user input (e.g. zero-sized engine)
      */
-    public ElectricalEngine(final String series, final String name, final int length,
+    public ElectricalEngine(String series, String name, int length,
-                            final boolean couplingFront, final boolean couplingBack) throws InvalidInputException {
+                            boolean couplingFront, boolean couplingBack) throws InvalidInputException {
         super(series, name, length, couplingFront, couplingBack);
     }
 

src/edu/kit/informatik/model/Engine.java

@@ -27,8 +27,8 @@ public abstract class Engine extends RollingStock {
      * @param couplingBack whether this engine should have a back coupling
      * @throws InvalidInputException on invalid user input (zero-sized coach)
      */
-    protected Engine(final String series, final String name,  final int length,
+    protected Engine(String series, String name,  int length,
-                     final boolean couplingFront, final boolean couplingBack) throws InvalidInputException {
+                     boolean couplingFront, boolean couplingBack) throws InvalidInputException {
         super(length, couplingFront, couplingBack);
         this.series = series;
         this.name = name;

src/edu/kit/informatik/model/ModelRailwaySimulation.java

@@ -47,7 +47,7 @@ public class ModelRailwaySimulation {
      * @return the positive identifier of the new track if successful, -1 if none available
      * @throws InvalidInputException if user input is invalid (e.g. zero length track)
      */
-    public int addTrack(final Vector2D start, final Vector2D end) throws InvalidInputException {
+    public int addTrack(Vector2D start, Vector2D end) throws InvalidInputException {
         return railNetwork.addTrack(start, end);
     }
 
@@ -90,7 +90,7 @@ public class ModelRailwaySimulation {
      * @return whether the switch could be set
      */
     public boolean setSwitch(int id, Vector2D position) {
-        boolean success = railNetwork.setSwitch(id, position);
+        final boolean success = railNetwork.setSwitch(id, position);
         if (success) { // derail trains on switch, explicitly not (!) printing any removed trains (source: forum post)
             trainManager.removeTrainsOnRail(railNetwork.getRail(id));
         }
@@ -102,7 +102,7 @@ public class ModelRailwaySimulation {
      * @throws InvalidInputException when the identifier is already in use
      */
     public void createEngine(Engine newEngine) throws InvalidInputException {
-        String id = newEngine.getIdentifier();
+        final String id = newEngine.getIdentifier();
         if (Stream.concat(engines.stream(), trainSets.stream())
                 .anyMatch(rollingStock -> rollingStock.getIdentifier().equals(id))) {
             throw new InvalidInputException("engine identifier already used");
@@ -118,7 +118,7 @@ public class ModelRailwaySimulation {
     public List<String> listEngines() {
         engines.sort(Comparator.comparing(Engine::getIdentifier));
         return engines.stream().map(engine -> {
-            String trainId = trainManager.getTrainContainingRollingStock(engine)
+            final String trainId = trainManager.getTrainContainingRollingStock(engine)
                     .map(train -> Integer.toString(train.getIdentifier()))
                     .orElse("none");
             return String.format("%s %s", trainId, engine);
@@ -136,7 +136,7 @@ public class ModelRailwaySimulation {
      */
     public int createCoach(CoachType coachType, int length,
                            boolean couplingFront, boolean couplingBack) throws InvalidInputException {
-        int id = getNextCoachIdentifier();
+        final int id = getNextCoachIdentifier();
         if (id < 0) {
             return -1;
         }
@@ -172,8 +172,8 @@ public class ModelRailwaySimulation {
      */
     public List<String> listCoaches() {
         return coaches.keySet().stream().sorted().map(coachId -> {
-            Coach coach = coaches.get(coachId);
+            final Coach coach = coaches.get(coachId);
-            String trainId = trainManager.getTrainContainingRollingStock(coach)
+            final String trainId = trainManager.getTrainContainingRollingStock(coach)
                     .map(train -> Integer.toString(train.getIdentifier()))
                     .orElse("none");
             return String.format("%d %s %s %d %b %b",
@@ -188,7 +188,7 @@ public class ModelRailwaySimulation {
      * @throws InvalidInputException if the identifier is already used
      */
     public void createTrainSet(TrainSet newTrainSet) throws InvalidInputException {
-        String id = newTrainSet.getIdentifier();
+        final String id = newTrainSet.getIdentifier();
         if (Stream.concat(engines.stream(), trainSets.stream())
                 .anyMatch(rollingStock -> rollingStock.getIdentifier().equals(id))) {
             throw new InvalidInputException("train set identifier already used");
@@ -217,7 +217,7 @@ public class ModelRailwaySimulation {
      * @return whether the rolling was successfully removed
      */
     public boolean deleteRollingStock(String id) {
-        RollingStock rollingStock = getRollingStock(id);
+        final RollingStock rollingStock = getRollingStock(id);
         if (trainManager.getTrainContainingRollingStock(rollingStock).isPresent()) {
             return false; // can not delete rolling stock in use
         }
@@ -231,7 +231,7 @@ public class ModelRailwaySimulation {
      */
     public RollingStock getRollingStock(String id) {
         if (Coach.IDENTIFIER_PATTERN.matcher(id).matches()) {
-            int coachId = Integer.parseInt(id.substring(1));
+            final int coachId = Integer.parseInt(id.substring(1));
             return coaches.get(coachId);
         } else {
             return Stream.concat(engines.stream(), trainSets.stream())
@@ -247,7 +247,7 @@ public class ModelRailwaySimulation {
      * @throws InvalidInputException if input is incorrect
      */
     public void addTrain(int trainId, String rollingStockId) throws InvalidInputException {
-        RollingStock rollingStock = getRollingStock(rollingStockId);
+        final RollingStock rollingStock = getRollingStock(rollingStockId);
         if (rollingStock == null) {
             throw new InvalidInputException("rolling stock not found");
         }
@@ -300,7 +300,7 @@ public class ModelRailwaySimulation {
      * @param speed amount of steps to move the trains
      * @throws InvalidInputException if the simulation is not yet ready
      */
-    public void step(final short speed) throws InvalidInputException {
+    public void step(short speed) throws InvalidInputException {
         trainManager.step(speed);
     }
 }

src/edu/kit/informatik/model/RailwayNetwork.java

@@ -166,7 +166,7 @@ public class RailwayNetwork {
      * @param position position to set the switch to
      * @return whether the switch could be set
      */
-    public boolean setSwitch(final int id, final Vector2D position) {
+    public boolean setSwitch(int id, Vector2D position) {
         final Rail toSwitch = rails.get(id);
         if (toSwitch != null) {
             return toSwitch.switchTo(position);

src/edu/kit/informatik/model/Track.java

@@ -22,12 +22,13 @@ public final class Track extends Rail {
 
     /**
      * Construct a new track. Start and end positions have to be on a straight line!
+     *
      * @param start start position of the track
      * @param end end position of the track
      * @param id identifier to use
      * @throws InvalidInputException if the positions are not on a straight line
      */
-    public Track(final Vector2D start, final Vector2D end, final int id) throws InvalidInputException {
+    public Track(Vector2D start, Vector2D end, int id) throws InvalidInputException {
         super(id);
         if (start.getX() != end.getX() && start.getY() != end.getY()) {
             throw new InvalidInputException("invalid track segment: not a straight line");
@@ -62,15 +63,11 @@ public final class Track extends Rail {
             return false;
         }
         if (start.getX() == end.getX() && position.getX() == start.getX()) {
-            long startY = start.getY();
+            return start.getY() < position.getY() && position.getY() < end.getY()
-            long endY = end.getY();
+                    || start.getY() > position.getY() && position.getY() > end.getY();
-            long positionY = position.getY();
-            return startY < positionY && positionY < endY || startY > positionY && positionY > endY;
         } else if (start.getY() == end.getY() && position.getY() == start.getY()) {
-            long startX = start.getX();
+            return start.getX() < position.getX() && position.getX() < end.getX()
-            long endX = end.getX();
+                    || start.getX() > position.getX() && position.getX() > end.getX();
-            long positionX = position.getX();
-            return startX < positionX && positionX < endX || startX > positionX && positionX > endX;
         }
         return false;
     }
@@ -82,17 +79,17 @@ public final class Track extends Rail {
 
     @Override
     public Vector2D move(Vector2D position, Vector2D direction, long steps) {
-        Vector2D nextPosition = position.add(direction.scale(steps));
+        final Vector2D nextPosition = position.add(direction.scale(steps));
         if (contains(nextPosition) || connectsTo(nextPosition)) {
             return nextPosition;
         } else if (direction.equals(getDirectionFrom(start))) {
             return new Vector2D(end);
         } else if (direction.equals(getDirectionFrom(end))) {
             return new Vector2D(start);
-        } else if (position.equals(end)) {
+        } else if (position.equals(end) && !direction.equals(getDirectionFrom(start))) {
             direction.copyFrom(getDirectionFrom(end));
             return move(position, getDirectionFrom(end), steps);
-        } else if (position.equals(start)) {
+        } else if (position.equals(start) && !direction.equals(getDirectionFrom(end))) {
             direction.copyFrom(getDirectionFrom(start));
             return move(position, getDirectionFrom(start), steps);
         }
@@ -101,13 +98,10 @@ public final class Track extends Rail {
 
     @Override
     public Vector2D getDirectionFrom(Vector2D position) {
-        // have to use long arithmetic here to avoid overflows
         if (start.equals(position)) {
-            return new Vector2D(Long.signum(end.getX() - start.getX()),
+            return new Vector2D(Long.signum(end.getX() - start.getX()), Long.signum(end.getY() - start.getY()));
-                    Long.signum(end.getY() - start.getY()));
         } else if (end.equals(position)) {
-            return new Vector2D(Long.signum(start.getX() - end.getX()),
+            return new Vector2D(Long.signum(start.getX() - end.getX()), Long.signum(start.getY() - end.getY()));
-                    Long.signum(start.getY() - end.getY()));
         } else {
             // in the middle of track, simply return direction from start
             return getDirectionFrom(start);
@@ -116,11 +110,8 @@ public final class Track extends Rail {
 
     @Override
     public boolean allowsDirectionFrom(Vector2D position, Vector2D direction) {
-        if (contains(position)) {
+        if (contains(position) || connectsTo(position)) {
-            return true;
+            return getDirectionFrom(position).isParallelTo(direction);
-        } else if (connectsTo(position)) {
-            return getDirectionFrom(position).equals(direction)
-                    || getDirectionFrom(position).negated().equals(direction);
         }
         return false;
     }
@@ -144,7 +135,7 @@ public final class Track extends Rail {
     }
 
     @Override
-    public boolean equals(final Object obj) {
+    public boolean equals(Object obj) {
         if (obj != null && getClass().equals(obj.getClass())) {
             final Track track = (Track) obj;
 

src/edu/kit/informatik/model/TrainManager.java

@@ -36,7 +36,7 @@ public final class TrainManager {
 
     /**
      * Construct a new train manager that will operate on the provided rail network.
-     * 
+     *
      * @param railNetwork rail network to use
      */
     public TrainManager(RailwayNetwork railNetwork) {
@@ -46,7 +46,7 @@ public final class TrainManager {
     /**
      * Check whether a train is on the rail with the specified identifier. Note that a train must be partially on that
      * rail, simply touching one of the end points is not enough.
-     * 
+     *
      * @param rail the rail to check
      * @return whether a train is on that rail
      */
@@ -56,6 +56,7 @@ public final class TrainManager {
 
     /**
      * Remove any trains on the rail with the specified identifier.
+     *
      * @param rail rail to clear
      */
     public void removeTrainsOnRail(Rail rail) {
@@ -64,7 +65,7 @@ public final class TrainManager {
 
     /**
      * Get the train containing the specified rolling stock.
-     * 
+     *
      * @param rollingStock rolling stock to search for
      * @return the train containing the rolling stock
      */
@@ -74,7 +75,7 @@ public final class TrainManager {
 
     /**
      * Add a rolling stock to an existing train or create a new one.
-     * 
+     *
      * @param trainId train identifier
      * @param rollingStock rolling stock to add
      * @throws InvalidInputException on invalid user input (e.g. rolling stock in use)
@@ -83,29 +84,30 @@ public final class TrainManager {
         if (getTrainContainingRollingStock(rollingStock).isPresent()) {
             throw new InvalidInputException("rolling stock already used");
         }
-        Train train = trains.get(trainId);
+        final Train train = trains.get(trainId);
         if (train != null && train.isPlaced()) {
             throw new InvalidInputException("can not add rolling stock to placed train");
         }
         if (train != null) {
             train.add(rollingStock);
         } else {
-            int correctId = getNextTrainIdentifier();
+            final int correctId = getNextTrainIdentifier();
             if (trainId != correctId) {
                 throw new InvalidInputException("new train identifier must be next free identifier");
             }
-            Train newTrain = new Train(trainId, rollingStock);
+            final Train newTrain = new Train(trainId, rollingStock);
             trains.put(trainId, newTrain);
         }
     }
 
     /**
-     * Delete a train.
+     * Delete a train. Will not delete rolling stock contained in that train.
+     *
      * @param trainId identifier of the train
      * @return whether the train could be deleted
      */
     public boolean deleteTrain(int trainId) {
-        Train train = trains.get(trainId);
+        final Train train = trains.get(trainId);
         if (train != null) {
             trains.remove(trainId);
             return true;
@@ -133,7 +135,7 @@ public final class TrainManager {
      * @throws InvalidInputException if train not found
      */
     public List<String> showTrain(int trainId) throws InvalidInputException {
-        Train train = trains.get(trainId);
+        final Train train = trains.get(trainId);
         if (train != null) {
             return train.show();
         } else {
@@ -150,7 +152,7 @@ public final class TrainManager {
      * @throws InvalidInputException when the train is too long
      */
     public boolean putTrain(int trainId, Vector2D position, Vector2D direction) throws InvalidInputException {
-        Train train = trains.get(trainId);
+        final Train train = trains.get(trainId);
         if (train == null) {
             throw new InvalidInputException("train not found");
         } else if (!train.isProperTrain()) {
@@ -163,7 +165,7 @@ public final class TrainManager {
             throw new InvalidInputException("switches not set up");
         }
         // attempt to place train
-        boolean placed = train.placeOn(railNetwork, position, direction);
+        final boolean placed = train.placeOn(railNetwork, position, direction);
         // check for collisions
         if (placed && !getPlacementCollisions().isEmpty()) {
             train.removeFromRails();
@@ -187,28 +189,21 @@ public final class TrainManager {
      * @param collisions list of collisions (never null, sometimes empty)
      */
     private void getStaticCollisions(List<Set<Train>> collisions) {
-        int maxId = trains.keySet().stream().max(Integer::compareTo).orElse(0);
+        final int maxId = trains.keySet().stream().max(Integer::compareTo).orElse(0);
-        for (int id1 = 1; id1 <= maxId; id1++) {
+        for (int id = 1; id <= maxId; id++) {
-            Train train1 = trains.get(id1);
+            final Train train1 = trains.get(id);
             if (train1 == null || !train1.isPlaced()) {
                 continue;
             }
-            HashSet<Train> collision = new HashSet<>();
+            final Set<Rail> occupiedRails = train1.getOccupiedRails();
-            // check for same position
+            // check for same position, and rail collisions
-            IntStream.rangeClosed(id1 + 1, maxId)
+            final Set<Train> collision = IntStream.rangeClosed(id + 1, maxId)
                     .mapToObj(trains::get)
                     .filter(Objects::nonNull)
                     .filter(Train::isPlaced)
-                    .filter(train1::touches)
+                    .filter(train -> train1.touches(train)
-                    .forEach(collision::add);
+                            || train.getOccupiedRails().stream().anyMatch(occupiedRails::contains))
-            // check for rail collisions
+                    .collect(Collectors.toSet());
-            Set<Rail> occupiedRails = train1.getOccupiedRails();
-            IntStream.rangeClosed(id1 + 1, maxId)
-                    .mapToObj(trains::get)
-                    .filter(Objects::nonNull)
-                    .filter(Train::isPlaced)
-                    .filter(train -> train.getOccupiedRails().stream().anyMatch(occupiedRails::contains))
-                    .forEach(collision::add);
             if (!collision.isEmpty()) {
                 collision.add(train1);
                 addToSetOrAddNew(collisions, collision);
@@ -218,25 +213,27 @@ public final class TrainManager {
 
     /**
      * Implementation of the silly *second* collision checking algorithm.
+     * Will put two trains in a collision even if they only touch the same rail.
+     *
      * @return list of collisions
      */
     private List<Set<Train>> getPlacementCollisions() {
-        List<Set<Train>> collisions = new ArrayList<>();
+        final List<Set<Train>> collisions = new ArrayList<>();
-        trains.values().stream().filter(Train::isPlaced).forEach(train1 -> {
+        trains.values().stream().filter(Train::isPlaced).forEach(train1 ->
-            trains.values().stream().filter(train -> train != train1).filter(Train::isPlaced).forEach(train2 -> {
+                trains.values().stream().filter(train -> train != train1).filter(Train::isPlaced).forEach(train2 -> {
-                Set<Rail> occupiedByTrain1 = train1.getOccupiedRails();
+                    final Set<Rail> occupiedByTrain1 = train1.getOccupiedRails();
-                Collections.addAll(occupiedByTrain1, railNetwork.findTouchingRails(train1.getFrontPosition()));
+                    Collections.addAll(occupiedByTrain1, railNetwork.findTouchingRails(train1.getFrontPosition()));
-                Collections.addAll(occupiedByTrain1, railNetwork.findTouchingRails(train1.getRearPosition()));
+                    Collections.addAll(occupiedByTrain1, railNetwork.findTouchingRails(train1.getRearPosition()));
-                Set<Rail> occupiedByTrain2 = train2.getOccupiedRails();
+                    final Set<Rail> occupiedByTrain2 = train2.getOccupiedRails();
-                Collections.addAll(occupiedByTrain2, railNetwork.findTouchingRails(train2.getFrontPosition()));
+                    Collections.addAll(occupiedByTrain2, railNetwork.findTouchingRails(train2.getFrontPosition()));
-                Collections.addAll(occupiedByTrain2, railNetwork.findTouchingRails(train2.getRearPosition()));
+                    Collections.addAll(occupiedByTrain2, railNetwork.findTouchingRails(train2.getRearPosition()));
-                occupiedByTrain2.retainAll(occupiedByTrain1);
+                    // calculate intersection
-                if (!occupiedByTrain2.isEmpty()) {
+                    occupiedByTrain2.retainAll(occupiedByTrain1);
-                    Set<Train> collision = Stream.of(train1, train2).collect(Collectors.toSet());
+                    if (!occupiedByTrain2.isEmpty()) {
-                    addToSetOrAddNew(collisions, collision);
+                        final Set<Train> collision = Stream.of(train1, train2).collect(Collectors.toSet());
-                }
+                        addToSetOrAddNew(collisions, collision);
-            });
+                    }
-        });
+                }));
         return collisions;
     }
 
@@ -266,19 +263,22 @@ public final class TrainManager {
     }
 
     /**
-     * Get collisions of moving the trains one step forward.
+     * Get collisions of moving the trains one step forward, removing crashing trains from the rails in the process.
+     *
      * @return list of collisions (never null, sometimes empty)
      */
     private List<Set<Train>> getCollisionsOfOneStep() {
-        List<Set<Train>> collisions = new ArrayList<>();
+        final List<Set<Train>> collisions = new ArrayList<>();
         trains.values().stream().filter(Train::isPlaced).forEach(train -> {
-            Vector2D position = train.getFrontPosition();
+            final Vector2D position = train.getFrontPosition();
-            Vector2D direction = train.getDirection();
+            final Vector2D direction = train.getDirection();
-            Vector2D nextPosition = railNetwork.move(position, direction, 1);
+            final Vector2D nextPosition = railNetwork.move(position, direction, 1);
             if (nextPosition == null || nextPosition.equals(position)) {
+                // train is derailing
                 train.moveTo(railNetwork, null);
                 collisions.add(new HashSet<>(Arrays.asList(train)));
             } else {
+                // train is moving successfully
                 train.moveTo(railNetwork, nextPosition);
             }
         });
@@ -288,21 +288,23 @@ public final class TrainManager {
     }
 
     /**
-     * Get collisions of moving the trains one step backward.
+     * Get collisions of moving the trains one step backward, removing crashing trains from the rails in the process.
+     *
      * @return list of collisions (never null, sometimes empty)
      */
     private List<Set<Train>> getCollisionsOfOneReverseStep() {
-        List<Set<Train>> collisions = new ArrayList<>();
+        final List<Set<Train>> collisions = new ArrayList<>();
         // perform step
         trains.values().stream().filter(Train::isPlaced).forEach(train -> {
-            Vector2D position = train.getRearPosition();
+            final Vector2D position = train.getRearPosition();
-            Vector2D direction = train.getRearDirection();
+            final Vector2D direction = train.getRearDirection();
-            Vector2D nextPosition = railNetwork.move(position, direction, 1);
+            final Vector2D nextPosition = railNetwork.move(position, direction, 1);
-            if (nextPosition == null
+            if (nextPosition == null || nextPosition.equals(position)) {
-                    || train.isOnPosition(nextPosition) && !train.getRearPosition().equals(train.getFrontPosition())) {
+                // derailing
                 train.moveBackTo(railNetwork, nextPosition);
                 collisions.add(new HashSet<>(Arrays.asList(train)));
             } else {
+                // train moving successfully
                 train.moveBackTo(railNetwork, nextPosition);
             }
         });
@@ -325,19 +327,21 @@ public final class TrainManager {
             return;
         }
 
-        List<Set<Train>> collisions = IntStream.range(0, Math.abs(speed))
+        final List<Set<Train>> collisions = IntStream.range(0, Math.abs(speed))
                 .mapToObj(step -> speed >= 0 ? getCollisionsOfOneStep() : getCollisionsOfOneReverseStep())
                 .flatMap(List::stream).collect(Collectors.toList());
 
-        for (int id : trains.keySet().stream().sorted().collect(Collectors.toList())) {
+        for (final int id : trains.keySet().stream().sorted().collect(Collectors.toList())) {
-            Train train = trains.get(id);
+            final Train train = trains.get(id);
-            Set<Train> collisionSet = collisions.stream()
+            final Set<Train> collisionSet = collisions.stream()
                     .filter(collision -> collision.contains(train))
                     .findFirst().orElse(null);
             if (collisionSet != null) { // print collision
-                int first = collisionSet.stream().min(Comparator.comparing(Train::getIdentifier)).get().getIdentifier();
+                final int first = collisionSet.stream()
+                        .min(Comparator.comparing(Train::getIdentifier)).get().getIdentifier();
                 if (train.getIdentifier() == first) { // only print each collision once
-                    List<Train> collision = collisionSet.stream().sorted(Comparator.comparing(Train::getIdentifier))
+                    final List<Train> collision = collisionSet.stream()
+                            .sorted(Comparator.comparing(Train::getIdentifier))
                             .collect(Collectors.toList());
                     Terminal.printLine("Crash of train " + String.join(",", collision.stream()
                             .map(crashedTrain -> Integer.toString(crashedTrain.getIdentifier()))

src/edu/kit/informatik/model/Vector2D.java

@@ -41,7 +41,7 @@ public class Vector2D {
      * @param input two 32-bit numbers separated by a comma
      * @return a vector containing the two numbers, null otherwise
      */
-    public static Vector2D parse(final String input) {
+    public static Vector2D parse(String input) {
         final String[] coordinates = input.split(",", 2);
         final int x = Integer.parseInt(coordinates[0]);
         final int y = Integer.parseInt(coordinates[1]);
@@ -62,6 +62,20 @@ public class Vector2D {
         return other != null ? Math.abs(this.x - other.x) + Math.abs(this.y - other.y) : 0;
     }
 
+    /**
+     * Check whether this vector is parallel to another vector. Note that this method only works for vectors that
+     * are parallel to one of the coordinate axes.
+     *
+     * @param other the point to measure distance to
+     * @return the manhattan distance
+     */
+    public boolean isParallelTo(Vector2D other) {
+        if (other == null) {
+            return false;
+        }
+        return x == 0 && other.x == 0 || y == 0 && other.y == 0;
+    }
+
     /**
      * @return a vector with separately (!) normalized components
      */

src/edu/kit/informatik/ui/command/AddSwitch.java

@@ -35,11 +35,11 @@ public class AddSwitch extends Command {
     private Vector2D end2;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         if (start == null) {
             throw new IllegalStateException("command not initialized");
         }
-        int id = simulation.addSwitch(start, end1, end2);
+        final int id = simulation.addSwitch(start, end1, end2);
         if (id == -1) {
             Terminal.printError("switch not connected to existing rails");
         } else {
@@ -52,7 +52,7 @@ public class AddSwitch extends Command {
         if (input == null || !input.startsWith(ADD_SWITCH)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = ADD_SWITCH_ARGUMENTS.matcher(input.substring(ADD_SWITCH.length()));
+        final Matcher matcher = ADD_SWITCH_ARGUMENTS.matcher(input.substring(ADD_SWITCH.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid add switch argument syntax");
         }

src/edu/kit/informatik/ui/command/AddTrack.java

@@ -31,11 +31,11 @@ public class AddTrack extends Command {
     private Vector2D end;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         if (start == null) {
             throw new IllegalStateException("command not initialized");
         }
-        int id = simulation.addTrack(start, end);
+        final int id = simulation.addTrack(start, end);
         if (id == -1) {
             Terminal.printError("id space exhausted");
         } else {
@@ -48,7 +48,7 @@ public class AddTrack extends Command {
         if (input == null || !input.startsWith(ADD_TRACK)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = ADD_TRACK_ARGUMENTS.matcher(input.substring(ADD_TRACK.length()));
+        final Matcher matcher = ADD_TRACK_ARGUMENTS.matcher(input.substring(ADD_TRACK.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid add track argument syntax");
         }

src/edu/kit/informatik/ui/command/AddTrain.java

@@ -32,12 +32,12 @@ public class AddTrain extends Command {
     private String rollingStockId;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         if (rollingStockId == null) {
             throw new IllegalStateException("command not initialized");
         }
         simulation.addTrain(trainId, rollingStockId);
-        RollingStock rollingStock = simulation.getRollingStock(rollingStockId);
+        final RollingStock rollingStock = simulation.getRollingStock(rollingStockId);
         Terminal.printLine(String.format("%s %s added to train %d",
                 rollingStock.description(), rollingStock.getIdentifier(), trainId));
     }
@@ -47,7 +47,7 @@ public class AddTrain extends Command {
         if (input == null || !input.startsWith(ADD_TRAIN)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = ADD_TRAIN_ARGUMENTS.matcher(input.substring(ADD_TRAIN.length()));
+        final Matcher matcher = ADD_TRAIN_ARGUMENTS.matcher(input.substring(ADD_TRAIN.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid add train arguments");
         }

src/edu/kit/informatik/ui/command/CommandFactory.java

@@ -31,6 +31,10 @@ public final class CommandFactory {
      */
     public static final String ROLLING_STOCK_IDENTIFIER
             = "(" + ALPHANUMERIC_WORD + "-" + ALPHANUMERIC_WORD + ")|" + Coach.IDENTIFIER_PATTERN;
+    /**
+     * Regex to accept one boolean (true or false).
+     */
+    public static final String BOOL = "true|false";
 
     /**
      * Name of the add track command.
@@ -143,9 +147,9 @@ public final class CommandFactory {
      * @throws InvalidInputException if user input is invalid
      */
     public static Command getCommand(String input) throws InvalidInputException {
-        for (Map.Entry<String, Supplier<Command>> entry : COMMANDS.entrySet()) {
+        for (final Map.Entry<String, Supplier<Command>> entry : COMMANDS.entrySet()) {
             if (input.startsWith(entry.getKey())) {
-                Command command = entry.getValue().get();
+                final Command command = entry.getValue().get();
                 command.parse(input);
                 return command;
             }

src/edu/kit/informatik/ui/command/CreateCoach.java

@@ -8,6 +8,8 @@ import edu.kit.informatik.ui.InvalidInputException;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import static edu.kit.informatik.model.Coach.COACH_TYPE;
+import static edu.kit.informatik.ui.command.CommandFactory.BOOL;
 import static edu.kit.informatik.ui.command.CommandFactory.CREATE_COACH;
 import static edu.kit.informatik.ui.command.CommandFactory.NUMBER;
 
@@ -19,7 +21,7 @@ import static edu.kit.informatik.ui.command.CommandFactory.NUMBER;
  */
 public class CreateCoach extends Command {
     private static final Pattern CREATE_COACH_ARGUMENTS
-            = Pattern.compile(" (passenger|freight|special) (" + NUMBER + ") (true|false) (true|false)");
+            = Pattern.compile(" (" + COACH_TYPE + ") (" + NUMBER + ") (" + BOOL + ") (" + BOOL + ")");
 
     /**
      * Type of the new coach.
@@ -39,11 +41,11 @@ public class CreateCoach extends Command {
     private boolean couplingBack;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         if (type == null) {
             throw new IllegalStateException("command not initialized");
         }
-        int id = simulation.createCoach(type, length, couplingFront, couplingBack);
+        final int id = simulation.createCoach(type, length, couplingFront, couplingBack);
         if (id == -1) {
             Terminal.printError("id space exhausted");
         } else {
@@ -56,7 +58,7 @@ public class CreateCoach extends Command {
         if (input == null || !input.startsWith(CREATE_COACH)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = CREATE_COACH_ARGUMENTS.matcher(input.substring(CREATE_COACH.length()));
+        final Matcher matcher = CREATE_COACH_ARGUMENTS.matcher(input.substring(CREATE_COACH.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid create coach arguments");
         }

src/edu/kit/informatik/ui/command/CreateEngine.java

@@ -14,6 +14,7 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import static edu.kit.informatik.ui.command.CommandFactory.ALPHANUMERIC_WORD;
+import static edu.kit.informatik.ui.command.CommandFactory.BOOL;
 import static edu.kit.informatik.ui.command.CommandFactory.CREATE_ENGINE;
 import static edu.kit.informatik.ui.command.CommandFactory.NUMBER;
 
@@ -26,7 +27,7 @@ import static edu.kit.informatik.ui.command.CommandFactory.NUMBER;
 public class CreateEngine extends Command {
     private static final Pattern CREATE_ENGINE_ARGUMENTS
         = Pattern.compile(" (electrical|diesel|steam) (" + ALPHANUMERIC_WORD + ") (" + ALPHANUMERIC_WORD + ") ("
-            + NUMBER + ") (true|false) (true|false)");
+            + NUMBER + ") (" + BOOL + ") (" + BOOL + ")");
 
     /**
      * Type of the new engine.
@@ -54,11 +55,11 @@ public class CreateEngine extends Command {
     private boolean couplingBack;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         if (type == null) {
             throw new IllegalStateException("command not initialized");
         }
-        Engine engine;
+        final Engine engine;
         switch (type) {
             case ELECTRICAL:
                 engine = new ElectricalEngine(series, name, length, couplingFront, couplingBack);
@@ -70,7 +71,7 @@ public class CreateEngine extends Command {
                 engine = new DieselEngine(series, name, length, couplingFront, couplingBack);
                 break;
             default:
-                throw new IllegalStateException("engine type is null!");
+                throw new IllegalStateException("command not initialized");
         }
         simulation.createEngine(engine);
         Terminal.printLine(engine.getIdentifier());
@@ -81,7 +82,7 @@ public class CreateEngine extends Command {
         if (input == null || !input.startsWith(CREATE_ENGINE)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = CREATE_ENGINE_ARGUMENTS.matcher(input.substring(CREATE_ENGINE.length()));
+        final Matcher matcher = CREATE_ENGINE_ARGUMENTS.matcher(input.substring(CREATE_ENGINE.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid create engine argument syntax");
         }

src/edu/kit/informatik/ui/command/CreateTrainSet.java

@@ -10,6 +10,7 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import static edu.kit.informatik.ui.command.CommandFactory.ALPHANUMERIC_WORD;
+import static edu.kit.informatik.ui.command.CommandFactory.BOOL;
 import static edu.kit.informatik.ui.command.CommandFactory.CREATE_TRAIN_SET;
 import static edu.kit.informatik.ui.command.CommandFactory.NUMBER;
 
@@ -22,7 +23,7 @@ import static edu.kit.informatik.ui.command.CommandFactory.NUMBER;
 public class CreateTrainSet extends Command {
     private static final Pattern CREATE_TRAIN_SET_ARGUMENTS
         = Pattern.compile(" (" + ALPHANUMERIC_WORD + ") (" + ALPHANUMERIC_WORD + ") ("
-            + NUMBER + ") (true|false) (true|false)");
+            + NUMBER + ") (" + BOOL + ") (" + BOOL + ")");
 
     /**
      * Series (class) of the new train set.
@@ -46,11 +47,11 @@ public class CreateTrainSet extends Command {
     private boolean couplingBack;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         if (name == null) {
             throw new IllegalStateException("command not initialized");
         }
-        TrainSet trainSet = new TrainSet(series, name, length, couplingFront, couplingBack);
+        final TrainSet trainSet = new TrainSet(series, name, length, couplingFront, couplingBack);
         simulation.createTrainSet(trainSet);
         Terminal.printLine(trainSet.getIdentifier());
     }
@@ -60,7 +61,7 @@ public class CreateTrainSet extends Command {
         if (input == null || !input.startsWith(CREATE_TRAIN_SET)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = CREATE_TRAIN_SET_ARGUMENTS.matcher(input.substring(CREATE_TRAIN_SET.length()));
+        final Matcher matcher = CREATE_TRAIN_SET_ARGUMENTS.matcher(input.substring(CREATE_TRAIN_SET.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid create train-set arguments");
         }

src/edu/kit/informatik/ui/command/DeleteRollingStock.java

@@ -17,8 +17,7 @@ import static edu.kit.informatik.ui.command.CommandFactory.ROLLING_STOCK_IDENTIF
  * @version 1.0
  */
 public class DeleteRollingStock extends Command {
-    private static final Pattern DELETE_ROLLING_STOCK_ARGUMENT
+    private static final Pattern DELETE_ROLLING_STOCK_ARGUMENT = Pattern.compile(" (" + ROLLING_STOCK_IDENTIFIER + ")");
-            = Pattern.compile(" (" + ROLLING_STOCK_IDENTIFIER + ")");
 
     /**
      * Identifier of the rolling stock to delete.
@@ -26,7 +25,7 @@ public class DeleteRollingStock extends Command {
     private String id;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
         if (id == null) {
             throw new IllegalStateException("command not initialized");
         }
@@ -42,7 +41,7 @@ public class DeleteRollingStock extends Command {
         if (input == null || !input.startsWith(DELETE_ROLLING_STOCK)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = DELETE_ROLLING_STOCK_ARGUMENT.matcher(input.substring(DELETE_ROLLING_STOCK.length()));
+        final Matcher matcher = DELETE_ROLLING_STOCK_ARGUMENT.matcher(input.substring(DELETE_ROLLING_STOCK.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid delete rolling stock argument");
         }

src/edu/kit/informatik/ui/command/DeleteTrack.java

@@ -20,7 +20,7 @@ public class DeleteTrack extends Command {
     private int id;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
         if (simulation.removeRail(id)) {
             Terminal.printLine("OK");
         } else {
@@ -33,7 +33,7 @@ public class DeleteTrack extends Command {
         if (input == null || !input.startsWith(DELETE_TRACK)) {
             throw new InvalidInputException("unknown command");
         }
-        String argument = input.substring(DELETE_TRACK.length());
+        final String argument = input.substring(DELETE_TRACK.length());
         if (!argument.matches(" " + NUMBER)) {
             throw new InvalidInputException("invalid/missing delete track argument");
         }

src/edu/kit/informatik/ui/command/DeleteTrain.java

@@ -20,7 +20,7 @@ public class DeleteTrain extends Command {
     private int id;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
         if (simulation.deleteTrain(id)) {
             Terminal.printLine("OK");
         } else {
@@ -33,7 +33,7 @@ public class DeleteTrain extends Command {
         if (input == null || !input.startsWith(DELETE_TRAIN)) {
             throw new InvalidInputException("unknown command");
         }
-        String argument = input.substring(DELETE_TRAIN.length());
+        final String argument = input.substring(DELETE_TRAIN.length());
         if (!argument.matches(" " + NUMBER)) {
             throw new InvalidInputException("invalid delete train argument");
         }

src/edu/kit/informatik/ui/command/ListCoaches.java

@@ -16,8 +16,8 @@ import static edu.kit.informatik.ui.command.CommandFactory.LIST_COACHES;
  */
 public class ListCoaches extends Command {
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
-        List<String> coaches = simulation.listCoaches();
+        final List<String> coaches = simulation.listCoaches();
         if (coaches.isEmpty()) {
             Terminal.printLine("No coach exists");
         } else {

src/edu/kit/informatik/ui/command/ListEngines.java

@@ -16,8 +16,8 @@ import static edu.kit.informatik.ui.command.CommandFactory.LIST_ENGINES;
  */
 public class ListEngines extends Command {
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
-        List<String> engines = simulation.listEngines();
+        final List<String> engines = simulation.listEngines();
         if (engines.isEmpty()) {
             Terminal.printLine("No engine exists");
         } else {

src/edu/kit/informatik/ui/command/ListTracks.java

@@ -16,8 +16,8 @@ import static edu.kit.informatik.ui.command.CommandFactory.LIST_TRACKS;
  */
 public class ListTracks extends Command {
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
-        List<String> tracks = simulation.listTracks();
+        final List<String> tracks = simulation.listTracks();
         if (tracks.isEmpty()) {
             Terminal.printLine("No track exists");
         } else {

src/edu/kit/informatik/ui/command/ListTrainSets.java

@@ -16,8 +16,8 @@ import static edu.kit.informatik.ui.command.CommandFactory.LIST_TRAIN_SETS;
  */
 public class ListTrainSets extends Command {
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
-        List<String> trainSets = simulation.listTrainSets();
+        final List<String> trainSets = simulation.listTrainSets();
         if (trainSets.isEmpty()) {
             Terminal.printLine("No train-set exists");
         } else {

src/edu/kit/informatik/ui/command/ListTrains.java

@@ -16,8 +16,8 @@ import static edu.kit.informatik.ui.command.CommandFactory.LIST_TRAINS;
  */
 public class ListTrains extends Command {
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
-        List<String> trains = simulation.listTrains();
+        final List<String> trains = simulation.listTrains();
         if (trains.isEmpty()) {
             Terminal.printLine("No train exists");
         } else {

src/edu/kit/informatik/ui/command/PutTrain.java

@@ -36,7 +36,7 @@ public class PutTrain extends Command {
     private Vector2D direction;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         if (point == null) {
             throw new IllegalStateException("command not initialized");
         }
@@ -52,7 +52,7 @@ public class PutTrain extends Command {
         if (input == null || !input.startsWith(PUT_TRAIN)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = PUT_TRAIN_ARGUMENTS.matcher(input.substring(PUT_TRAIN.length()));
+        final Matcher matcher = PUT_TRAIN_ARGUMENTS.matcher(input.substring(PUT_TRAIN.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid put train arguments");
         }

src/edu/kit/informatik/ui/command/SetSwitch.java

@@ -32,7 +32,7 @@ public class SetSwitch extends Command {
     private Vector2D point;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) {
+    public void apply(ModelRailwaySimulation simulation) {
         if (point == null) {
             throw new IllegalStateException("command not initialized");
         }
@@ -48,7 +48,7 @@ public class SetSwitch extends Command {
         if (input == null || !input.startsWith(SET_SWITCH)) {
             throw new InvalidInputException("unknown command");
         }
-        Matcher matcher = SET_SWITCH_ARGUMENTS.matcher(input.substring(SET_SWITCH.length()));
+        final Matcher matcher = SET_SWITCH_ARGUMENTS.matcher(input.substring(SET_SWITCH.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid set switch argument syntax");
         }

src/edu/kit/informatik/ui/command/ShowTrain.java

@@ -20,7 +20,7 @@ public class ShowTrain extends Command {
     private int id;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         simulation.showTrain(id).forEach(Terminal::printLine);
     }
 
@@ -29,7 +29,7 @@ public class ShowTrain extends Command {
         if (input == null || !input.startsWith(SHOW_TRAIN)) {
             throw new InvalidInputException("unknown command");
         }
-        String argument = input.substring(SHOW_TRAIN.length());
+        final String argument = input.substring(SHOW_TRAIN.length());
         if (!argument.matches(" " + NUMBER)) {
             throw new InvalidInputException("invalid show train argument");
         }

src/edu/kit/informatik/ui/command/Step.java

@@ -3,6 +3,7 @@ package edu.kit.informatik.ui.command;
 import edu.kit.informatik.model.ModelRailwaySimulation;
 import edu.kit.informatik.ui.InvalidInputException;
 
+import static edu.kit.informatik.ui.command.CommandFactory.NUMBER;
 import static edu.kit.informatik.ui.command.CommandFactory.STEP;
 
 /**
@@ -18,7 +19,7 @@ public class Step extends Command {
     private short speed;
 
     @Override
-    public void apply(final ModelRailwaySimulation simulation) throws InvalidInputException {
+    public void apply(ModelRailwaySimulation simulation) throws InvalidInputException {
         simulation.step(speed);
     }
 
@@ -27,8 +28,8 @@ public class Step extends Command {
         if (input == null || !input.startsWith(STEP)) {
             throw new InvalidInputException("unknown command");
         }
-        String argument = input.substring(STEP.length());
+        final String argument = input.substring(STEP.length());
-        if (!argument.matches(" [+-]?\\d+")) {
+        if (!argument.matches(" " + NUMBER)) {
             throw new InvalidInputException("invalid step argument");
         }
         speed = Short.parseShort(argument.substring(1));