Improve arc memory management.

src/main/org/insa/graph/Arc.java

@@ -0,0 +1,45 @@
+package org.insa.graph;
+
+import java.util.List;
+
+/**
+ * Interface representing an arc in the graph - Arc is an interface and not a
+ * class to allow us to represent two-ways roads in a memory efficient manner
+ * (without having to duplicate attributes).
+ * 
+ * @see ArcForward
+ * @see ArcBackward
+ *
+ */
+public interface Arc {
+
+    /**
+     * @return Origin node of this arc.
+     */
+    public Node getOrigin();
+
+    /**
+     * @return Destination node of this arc.
+     */
+    public Node getDestination();
+
+    /**
+     * @return Length of this arc, in meters.
+     */
+    public int getLength();
+
+    /**
+     * @return Minimum time required to travel this arc, in seconds.
+     */
+    public double getMinimumTravelTime();
+
+    /**
+     * @return Road information for this arc.
+     */
+    public RoadInformation getRoadInformation();
+
+    /**
+     * @return Points representing segments of this arc.
+     */
+    public List<Point> getPoints();
+}

src/main/org/insa/graph/ArcBackward.java

@@ -0,0 +1,61 @@
+package org.insa.graph;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Implementation of Arc that represents a "backward" arc in a graph, i.e. an
+ * arc that is the reverse of another one. This arc only holds a reference to
+ * the original arc.
+ *
+ */
+public class ArcBackward implements Arc {
+
+    // Original arc
+    private final ArcForward originalArc;
+
+    /**
+     * Create a new backward arc which corresponds to the reverse arc of the given
+     * arc.
+     * 
+     * @param originalArc
+     */
+    public ArcBackward(ArcForward originalArc) {
+        this.originalArc = originalArc;
+        this.originalArc.getDestination().addSuccessor(this);
+    }
+
+    @Override
+    public Node getOrigin() {
+        return this.originalArc.getDestination();
+    }
+
+    @Override
+    public Node getDestination() {
+        return this.originalArc.getOrigin();
+    }
+
+    @Override
+    public int getLength() {
+        return this.originalArc.getLength();
+    }
+
+    @Override
+    public double getMinimumTravelTime() {
+        return this.originalArc.getMinimumTravelTime();
+    }
+
+    @Override
+    public RoadInformation getRoadInformation() {
+        return this.originalArc.getRoadInformation();
+    }
+
+    @Override
+    public List<Point> getPoints() {
+        List<Point> pts = new ArrayList<>(this.originalArc.getPoints());
+        Collections.reverse(pts);
+        return pts;
+    }
+
+}

src/main/org/insa/graph/ArcForward.java

@@ -4,7 +4,12 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
-public class Arc {
+/**
+ * Implementation of Arc that represents a "forward" arc in a graph, this is the
+ * arc implementation that stores data relative to the arc.
+ *
+ */
+public class ArcForward implements Arc {
 
     // Destination node.
     private final Node origin, destination;
@@ -27,7 +32,8 @@ public class Arc {
      * @param roadInformation Road information for this arc.
      * @param points Points representing this arc.
      */
-    public Arc(Node origin, Node dest, int length, RoadInformation roadInformation, ArrayList<Point> points) {
+    public ArcForward(Node origin, Node dest, int length, RoadInformation roadInformation,
+            ArrayList<Point> points) {
         this.origin = origin;
         this.destination = dest;
         this.length = length;
@@ -37,42 +43,42 @@ public class Arc {
     }
 
     /**
-     * @return Origin node of this arc.
+     * {@inheritDoc}
      */
     public Node getOrigin() {
         return origin;
     }
 
     /**
-     * @return Destination node of this arc.
+     * {@inheritDoc}
      */
     public Node getDestination() {
         return destination;
     }
 
     /**
-     * @return Length of this arc, in meters.
+     * {@inheritDoc}
      */
     public int getLength() {
         return length;
     }
 
     /**
-     * @return Minimum time required to travel this arc, in seconds.
+     * {@inheritDoc}
      */
     public double getMinimumTravelTime() {
         return getLength() * 3600.0 / (info.getMaximumSpeed() * 1000.0);
     }
 
     /**
-     * @return Road information for this arc.
+     * {@inheritDoc}
      */
     public RoadInformation getRoadInformation() {
         return info;
     }
 
     /**
-     * @return Points representing segments of this arc.
+     * {@inheritDoc}
      */
     public List<Point> getPoints() {
         return Collections.unmodifiableList(points);

src/main/org/insa/graph/Node.java

@@ -59,7 +59,6 @@ public class Node implements Comparable<Node> {
 
     /*
      * (non-Javadoc)
-     * 
      * @see java.lang.Object#equals(java.lang.Object)
      */
     @Override
@@ -72,7 +71,6 @@ public class Node implements Comparable<Node> {
 
     /*
      * (non-Javadoc)
-     * 
      * @see java.lang.Comparable#compareTo(java.lang.Object)
      */
     @Override

src/main/org/insa/graph/Point.java

@@ -17,21 +17,23 @@ public class Point {
      * @return Distance between the two given points, in meters.
      */
     public static double distance(Point p1, Point p2) {
-        double sinLat = Math.sin(Math.toRadians(p1.getLatitude())) * Math.sin(Math.toRadians(p2.getLatitude()));
+        double sinLat = Math.sin(Math.toRadians(p1.getLatitude()))
-        double cosLat = Math.cos(Math.toRadians(p1.getLatitude())) * Math.cos(Math.toRadians(p2.getLatitude()));
+                * Math.sin(Math.toRadians(p2.getLatitude()));
+        double cosLat = Math.cos(Math.toRadians(p1.getLatitude()))
+                * Math.cos(Math.toRadians(p2.getLatitude()));
         double cosLong = Math.cos(Math.toRadians(p2.getLongitude() - p1.getLongitude()));
         return EARTH_RADIUS * Math.acos(sinLat + cosLat * cosLong);
     }
 
     // Longitude and latitude of the point.
-    private final double longitude, latitude;
+    private final float longitude, latitude;
 
     /**
      * 
      * @param longitude Longitude of the point, in degrees.
      * @param latitude Latitude of the point, in degrees.
      */
-    public Point(double longitude, double latitude) {
+    public Point(float longitude, float latitude) {
         this.longitude = longitude;
         this.latitude = latitude;
     }
@@ -39,14 +41,14 @@ public class Point {
     /**
      * @return Longitude of this point (in degrees).
      */
-    public double getLongitude() {
+    public float getLongitude() {
         return longitude;
     }
 
     /**
      * @return Latitude of this point (in degrees).
      */
-    public double getLatitude() {
+    public float getLatitude() {
         return latitude;
     }
 
@@ -63,7 +65,6 @@ public class Point {
 
     /*
      * (non-Javadoc)
-     * 
      * @see java.lang.Object#toString()
      */
     @Override

src/main/org/insa/graph/RoadInformation.java

@@ -45,7 +45,8 @@ public class RoadInformation {
     // Name of the road.
     private final String name;
 
-    public RoadInformation(RoadType roadType, AccessRestrictions access, boolean isOneWay, int maxSpeed, String name) {
+    public RoadInformation(RoadType roadType, AccessRestrictions access, boolean isOneWay,
+            int maxSpeed, String name) {
         this.type = roadType;
         this.access = access;
         this.oneway = isOneWay;
@@ -53,8 +54,6 @@ public class RoadInformation {
         this.name = name;
     }
 
-    // Access information
-
     /**
      * @return true if this is a private road.
      */
@@ -92,7 +91,6 @@ public class RoadInformation {
 
     /*
      * (non-Javadoc)
-     * 
      * @see java.lang.Object#toString()
      */
     @Override
@@ -104,7 +102,8 @@ public class RoadInformation {
         if (getType() == RoadType.MOTORWAY) {
             typeAsString = "highway";
         }
-        return typeAsString + " : " + getName() + " " + (isOneWay() ? " (oneway) " : "") + maxSpeed + " km/h (max.)";
+        return typeAsString + " : " + getName() + " " + (isOneWay() ? " (oneway) " : "") + maxSpeed
+                + " km/h (max.)";
     }
 
 }

src/main/org/insa/graph/io/BinaryGraphReaderInsa2018.java

@@ -3,13 +3,13 @@ package org.insa.graph.io;
 import java.io.DataInputStream;
 import java.io.IOException;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.EnumMap;
 
 import org.insa.graph.AccessRestrictions;
 import org.insa.graph.AccessRestrictions.AccessMode;
 import org.insa.graph.AccessRestrictions.AccessRestriction;
-import org.insa.graph.Arc;
+import org.insa.graph.ArcForward;
+import org.insa.graph.ArcBackward;
 import org.insa.graph.Graph;
 import org.insa.graph.GraphInformation;
 import org.insa.graph.Node;
@@ -41,16 +41,17 @@ public class BinaryGraphReaderInsa2018 extends BinaryReader implements GraphRead
         // the order correspond to the 4 bits value (i.e. FORBIDDEN is 0 or PRIVATE is
         // 2) - UKNOWN is not included because value above 6 (FORESTRY) are all
         // considered unknown.
-        final AccessRestriction[] allRestrictions = new AccessRestriction[] { AccessRestriction.FORBIDDEN,
+        final AccessRestriction[] allRestrictions = new AccessRestriction[]{
-                AccessRestriction.ALLOWED, AccessRestriction.PRIVATE, AccessRestriction.DESTINATION,
+                AccessRestriction.FORBIDDEN, AccessRestriction.ALLOWED, AccessRestriction.PRIVATE,
-                AccessRestriction.DELIVERY, AccessRestriction.CUSTOMERS, AccessRestriction.FORESTRY };
+                AccessRestriction.DESTINATION, AccessRestriction.DELIVERY,
+                AccessRestriction.CUSTOMERS, AccessRestriction.FORESTRY };
 
         // The order of values inside this array is VERY IMPORTANT: The order is such
         // that each 4-bits group of the long value is processed in the correct order,
         // i.e. FOOT is processed first (4 lowest bits), and so on.
-        final AccessMode[] allModes = new AccessMode[] { AccessMode.FOOT, null, AccessMode.BICYCLE,
+        final AccessMode[] allModes = new AccessMode[]{ AccessMode.FOOT, null, AccessMode.BICYCLE,
-                AccessMode.SMALL_MOTORCYCLE, AccessMode.AGRICULTURAL, AccessMode.MOTORCYCLE, AccessMode.MOTORCAR,
+                AccessMode.SMALL_MOTORCYCLE, AccessMode.AGRICULTURAL, AccessMode.MOTORCYCLE,
-                AccessMode.HEAVY_GOODS, null, AccessMode.PUBLIC_TRANSPORT };
+                AccessMode.MOTORCAR, AccessMode.HEAVY_GOODS, null, AccessMode.PUBLIC_TRANSPORT };
 
         // fill maps...
         EnumMap<AccessMode, AccessRestriction> restrictions = new EnumMap<>(AccessMode.class);
@@ -69,7 +70,7 @@ public class BinaryGraphReaderInsa2018 extends BinaryReader implements GraphRead
             copyAccess = copyAccess >> 4;
         }
 
-        return new AccessRestrictions(restrictions, access);
+        return new AccessRestrictions(restrictions);
     }
 
     /**
@@ -228,7 +229,8 @@ public class BinaryGraphReaderInsa2018 extends BinaryReader implements GraphRead
                     float dlon = (dis.readShort()) / 2.0e5f;
                     float dlat = (dis.readShort()) / 2.0e5f;
 
-                    points.add(new Point(lastPoint.getLongitude() + dlon, lastPoint.getLatitude() + dlat));
+                    points.add(new Point(lastPoint.getLongitude() + dlon,
+                            lastPoint.getLatitude() + dlat));
                 }
 
                 points.add(nodes.get(destNode).getPoint());
@@ -238,14 +240,15 @@ public class BinaryGraphReaderInsa2018 extends BinaryReader implements GraphRead
                 Node dest = nodes.get(destNode);
 
                 // Add successor to initial arc.
-                Arc arc = new Arc(orig, dest, length, info, points);
+                ArcForward arc = new ArcForward(orig, dest, length, info, points);
 
                 // And reverse arc if its a two-way road.
                 if (!info.isOneWay()) {
                     // Add without segments.
-                    ArrayList<Point> rPoints = new ArrayList<Point>(points);
+                    // ArrayList<Point> rPoints = new ArrayList<Point>(points);
-                    Collections.reverse(rPoints);
+                    // Collections.reverse(rPoints);
-                    new Arc(dest, orig, length, info, rPoints);
+                    // new Arc(dest, orig, length, info, null);
+                    new ArcBackward(arc);
                 }
                 observers.forEach((observer) -> observer.notifyNewArcRead(arc));
             }
@@ -273,7 +276,12 @@ public class BinaryGraphReaderInsa2018 extends BinaryReader implements GraphRead
         if (getCurrentVersion() >= 7) {
             access = toAccessInformationV7(dis.readLong());
         }
-        return new RoadInformation(toRoadType(type), access, (x & 0x80) > 0, (x & 0x7F) * 5, dis.readUTF());
+        else if (getCurrentVersion() >= 6) {
+            // TODO: Try to create something...
+            dis.readUnsignedShort();
+        }
+        return new RoadInformation(toRoadType(type), access, (x & 0x80) > 0, (x & 0x7F) * 5,
+                dis.readUTF());
     }
 
 }

src/main/org/insa/graphics/drawing/components/BasicDrawing.java

@@ -21,6 +21,7 @@ import java.util.List;
 
 import javax.swing.JPanel;
 
+import org.insa.graph.ArcForward;
 import org.insa.graph.Arc;
 import org.insa.graph.Graph;
 import org.insa.graph.Node;
@@ -132,8 +133,8 @@ public class BasicDrawing extends JPanel implements Drawing {
             int px = BasicDrawing.this.projx(getPoint().getLongitude());
             int py = BasicDrawing.this.projy(getPoint().getLatitude());
 
-            graphics.drawImage(this.image, px - MARKER_WIDTH / 2, py - MARKER_HEIGHT, MARKER_WIDTH, MARKER_HEIGHT,
+            graphics.drawImage(this.image, px - MARKER_WIDTH / 2, py - MARKER_HEIGHT, MARKER_WIDTH,
-                    BasicDrawing.this);
+                    MARKER_HEIGHT, BasicDrawing.this);
         }
 
     };
@@ -282,7 +283,8 @@ public class BasicDrawing extends JPanel implements Drawing {
     private Graphics2D graphGraphics = null;
 
     // List of image for markers
-    private List<BasicOverlay> overlays = Collections.synchronizedList(new ArrayList<BasicOverlay>());
+    private List<BasicOverlay> overlays = Collections
+            .synchronizedList(new ArrayList<BasicOverlay>());
 
     // Mapping DrawingClickListener -> MouseEventListener
     private List<DrawingClickListener> drawingClickListeners = new ArrayList<>();
@@ -295,11 +297,13 @@ public class BasicDrawing extends JPanel implements Drawing {
      * 
      */
     public BasicDrawing() {
-        this.zoomAndPanListener = new ZoomAndPanListener(this, ZoomAndPanListener.DEFAULT_MIN_ZOOM_LEVEL, 20, 1.2);
+        this.zoomAndPanListener = new ZoomAndPanListener(this,
+                ZoomAndPanListener.DEFAULT_MIN_ZOOM_LEVEL, 20, 1.2);
 
         // Try...
         try {
-            this.zoomControls = new MapZoomControls(this, 0, ZoomAndPanListener.DEFAULT_MIN_ZOOM_LEVEL, 20);
+            this.zoomControls = new MapZoomControls(this, 0,
+                    ZoomAndPanListener.DEFAULT_MIN_ZOOM_LEVEL, 20);
             this.zoomControls.addZoomInListener(new ActionListener() {
                 @Override
                 public void actionPerformed(ActionEvent e) {
@@ -394,7 +398,8 @@ public class BasicDrawing extends JPanel implements Drawing {
         // Get the point using the inverse transform of the Zoom/Pan object, this gives
         // us
         // a point within the drawing box (between [0, 0] and [width, height]).
-        Point2D ptDst = this.zoomAndPanListener.getCoordTransform().inverseTransform(event.getPoint(), null);
+        Point2D ptDst = this.zoomAndPanListener.getCoordTransform()
+                .inverseTransform(event.getPoint(), null);
 
         // Inverse the "projection" on x/y to get longitude and latitude.
         double lon = ptDst.getX();
@@ -403,7 +408,7 @@ public class BasicDrawing extends JPanel implements Drawing {
         lat = (1 - lat / this.height) * (this.lat2 - this.lat1) + this.lat1;
 
         // Return a new point.
-        return new Point(lon, lat);
+        return new Point((float) lon, (float) lat);
     }
 
     @Override
@@ -461,9 +466,9 @@ public class BasicDrawing extends JPanel implements Drawing {
      * 
      * @param arc Arc to draw.
      * @param palette Palette to use to retrieve color and width for arc, or null to
-     *        use current settings.
+     * use current settings.
      */
-    protected void drawArc(Arc arc, GraphPalette palette, boolean repaint) {
+    protected void drawArc(ArcForward arc, GraphPalette palette, boolean repaint) {
         List<Point> pts = arc.getPoints();
         if (!pts.isEmpty()) {
             if (palette != null) {
@@ -500,8 +505,8 @@ public class BasicDrawing extends JPanel implements Drawing {
         this.clear();
 
         // Find minimum/maximum longitude and latitude.
-        double minLon = Double.POSITIVE_INFINITY, minLat = Double.POSITIVE_INFINITY, maxLon = Double.NEGATIVE_INFINITY,
+        double minLon = Double.POSITIVE_INFINITY, minLat = Double.POSITIVE_INFINITY,
-                maxLat = Double.NEGATIVE_INFINITY;
+                maxLon = Double.NEGATIVE_INFINITY, maxLat = Double.NEGATIVE_INFINITY;
         for (Node node: graph.getNodes()) {
             Point pt = node.getPoint();
             if (pt.getLatitude() < minLat) {
@@ -539,7 +544,8 @@ public class BasicDrawing extends JPanel implements Drawing {
         }
 
         // Create the image
-        BufferedImage img = new BufferedImage(this.width, this.height, BufferedImage.TYPE_3BYTE_BGR);
+        BufferedImage img = new BufferedImage(this.width, this.height,
+                BufferedImage.TYPE_3BYTE_BGR);
         this.graphImage = img;
         this.graphGraphics = img.createGraphics();
         this.graphGraphics.setBackground(Color.WHITE);
@@ -547,10 +553,12 @@ public class BasicDrawing extends JPanel implements Drawing {
 
         // Set the zoom and pan listener
 
-        double scale = 1 / Math.max(this.width / (double) this.getWidth(), this.height / (double) this.getHeight());
+        double scale = 1 / Math.max(this.width / (double) this.getWidth(),
+                this.height / (double) this.getHeight());
 
         this.zoomAndPanListener.setCoordTransform(this.graphGraphics.getTransform());
-        this.zoomAndPanListener.getCoordTransform().translate((this.getWidth() - this.width * scale) / 2,
+        this.zoomAndPanListener.getCoordTransform().translate(
+                (this.getWidth() - this.width * scale) / 2,
                 (this.getHeight() - this.height * scale) / 2);
         this.zoomAndPanListener.getCoordTransform().scale(scale, scale);
         this.zoomAndPanListener.setZoomLevel(0);
@@ -575,8 +583,8 @@ public class BasicDrawing extends JPanel implements Drawing {
 
         for (Node node: graph.getNodes()) {
             for (Arc arc: node.getSuccessors()) {
-                if (arc.getRoadInformation().isOneWay() || arc.getOrigin().compareTo(arc.getDestination()) < 0) {
+                if (arc instanceof ArcForward) { // draw only "true" arcs
-                    drawArc(arc, palette, false);
+                    drawArc((ArcForward) arc, palette, false);
                 }
             }
             if (node.getId() % repaintModulo == 0) {

src/test/org/insa/graph/PathTest.java

@@ -22,7 +22,7 @@ public class PathTest {
 
     // List of arcs in the graph, a2b is the arc from node A (0) to B (1).
     @SuppressWarnings("unused")
-    private static Arc a2b, a2c, a2e, b2c, c2d_1, c2d_2, c2d_3, c2a, d2a, d2e, e2d;
+    private static ArcForward a2b, a2c, a2e, b2c, c2d_1, c2d_2, c2d_3, c2a, d2a, d2e, e2d;
 
     // Some paths...
     private static Path emptyPath, shortPath, longPath, loopPath, longLoopPath, invalidPath;
@@ -41,25 +41,26 @@ public class PathTest {
         }
 
         // Add arcs...
-        a2b = new Arc(nodes[0], nodes[1], 10, speed10, null);
+        a2b = new ArcForward(nodes[0], nodes[1], 10, speed10, null);
-        a2c = new Arc(nodes[0], nodes[2], 15, speed10, null);
+        a2c = new ArcForward(nodes[0], nodes[2], 15, speed10, null);
-        a2e = new Arc(nodes[0], nodes[4], 15, speed20, null);
+        a2e = new ArcForward(nodes[0], nodes[4], 15, speed20, null);
-        b2c = new Arc(nodes[1], nodes[2], 10, speed10, null);
+        b2c = new ArcForward(nodes[1], nodes[2], 10, speed10, null);
-        c2d_1 = new Arc(nodes[2], nodes[3], 20, speed10, null);
+        c2d_1 = new ArcForward(nodes[2], nodes[3], 20, speed10, null);
-        c2d_2 = new Arc(nodes[2], nodes[3], 10, speed10, null);
+        c2d_2 = new ArcForward(nodes[2], nodes[3], 10, speed10, null);
-        c2d_3 = new Arc(nodes[2], nodes[3], 15, speed20, null);
+        c2d_3 = new ArcForward(nodes[2], nodes[3], 15, speed20, null);
-        d2a = new Arc(nodes[3], nodes[0], 15, speed10, null);
+        d2a = new ArcForward(nodes[3], nodes[0], 15, speed10, null);
-        d2e = new Arc(nodes[3], nodes[4], 20, speed20, null);
+        d2e = new ArcForward(nodes[3], nodes[4], 20, speed20, null);
-        e2d = new Arc(nodes[4], nodes[0], 10, speed10, null);
+        e2d = new ArcForward(nodes[4], nodes[0], 10, speed10, null);
 
         graph = new Graph("ID", "", Arrays.asList(nodes), null);
 
         emptyPath = new Path(graph, new ArrayList<Arc>());
-        shortPath = new Path(graph, Arrays.asList(new Arc[] { a2b, b2c, c2d_1 }));
+        shortPath = new Path(graph, Arrays.asList(new ArcForward[]{ a2b, b2c, c2d_1 }));
-        longPath = new Path(graph, Arrays.asList(new Arc[] { a2b, b2c, c2d_1, d2e }));
+        longPath = new Path(graph, Arrays.asList(new ArcForward[]{ a2b, b2c, c2d_1, d2e }));
-        loopPath = new Path(graph, Arrays.asList(new Arc[] { a2b, b2c, c2d_1, d2a }));
+        loopPath = new Path(graph, Arrays.asList(new ArcForward[]{ a2b, b2c, c2d_1, d2a }));
-        longLoopPath = new Path(graph, Arrays.asList(new Arc[] { a2b, b2c, c2d_1, d2a, a2c, c2d_3, d2a, a2b, b2c }));
+        longLoopPath = new Path(graph,
-        invalidPath = new Path(graph, Arrays.asList(new Arc[] { a2b, c2d_1, d2e }));
+                Arrays.asList(new ArcForward[]{ a2b, b2c, c2d_1, d2a, a2c, c2d_3, d2a, a2b, b2c }));
+        invalidPath = new Path(graph, Arrays.asList(new ArcForward[]{ a2b, c2d_1, d2e }));
 
     }
 
@@ -121,11 +122,12 @@ public class PathTest {
     @Test
     public void testCreateFastestPathFromNodes() {
         Path path;
-        Arc[] expected;
+        ArcForward[] expected;
 
         // Simple construction
-        path = Path.createFastestPathFromNodes(graph, Arrays.asList(new Node[] { nodes[0], nodes[1], nodes[2] }));
+        path = Path.createFastestPathFromNodes(graph,
-        expected = new Arc[] { a2b, b2c };
+                Arrays.asList(new Node[]{ nodes[0], nodes[1], nodes[2] }));
+        expected = new ArcForward[]{ a2b, b2c };
         assertEquals(expected.length, path.getArcs().size());
         for (int i = 0; i < expected.length; ++i) {
             assertEquals(expected[i], path.getArcs().get(i));
@@ -133,8 +135,8 @@ public class PathTest {
 
         // Not so simple construction
         path = Path.createFastestPathFromNodes(graph,
-                Arrays.asList(new Node[] { nodes[0], nodes[1], nodes[2], nodes[3] }));
+                Arrays.asList(new Node[]{ nodes[0], nodes[1], nodes[2], nodes[3] }));
-        expected = new Arc[] { a2b, b2c, c2d_3 };
+        expected = new ArcForward[]{ a2b, b2c, c2d_3 };
         assertEquals(expected.length, path.getArcs().size());
         for (int i = 0; i < expected.length; ++i) {
             assertEquals(expected[i], path.getArcs().get(i));
@@ -144,11 +146,12 @@ public class PathTest {
     @Test
     public void testCreateShortestPathFromNodes() {
         Path path;
-        Arc[] expected;
+        ArcForward[] expected;
 
         // Simple construction
-        path = Path.createShortestPathFromNodes(graph, Arrays.asList(new Node[] { nodes[0], nodes[1], nodes[2] }));
+        path = Path.createShortestPathFromNodes(graph,
-        expected = new Arc[] { a2b, b2c };
+                Arrays.asList(new Node[]{ nodes[0], nodes[1], nodes[2] }));
+        expected = new ArcForward[]{ a2b, b2c };
         assertEquals(expected.length, path.getArcs().size());
         for (int i = 0; i < expected.length; ++i) {
             assertEquals(expected[i], path.getArcs().get(i));
@@ -156,8 +159,8 @@ public class PathTest {
 
         // Not so simple construction
         path = Path.createShortestPathFromNodes(graph,
-                Arrays.asList(new Node[] { nodes[0], nodes[1], nodes[2], nodes[3] }));
+                Arrays.asList(new Node[]{ nodes[0], nodes[1], nodes[2], nodes[3] }));
-        expected = new Arc[] { a2b, b2c, c2d_2 };
+        expected = new ArcForward[]{ a2b, b2c, c2d_2 };
         assertEquals(expected.length, path.getArcs().size());
         for (int i = 0; i < expected.length; ++i) {
             assertEquals(expected[i], path.getArcs().get(i));
@@ -166,12 +169,12 @@ public class PathTest {
 
     @Test(expected = IllegalArgumentException.class)
     public void testCreateFastestPathFromNodesException() {
-        Path.createFastestPathFromNodes(graph, Arrays.asList(new Node[] { nodes[1], nodes[0] }));
+        Path.createFastestPathFromNodes(graph, Arrays.asList(new Node[]{ nodes[1], nodes[0] }));
     }
 
     @Test(expected = IllegalArgumentException.class)
     public void testCreateShortestPathFromNodesException() {
-        Path.createShortestPathFromNodes(graph, Arrays.asList(new Node[] { nodes[1], nodes[0] }));
+        Path.createShortestPathFromNodes(graph, Arrays.asList(new Node[]{ nodes[1], nodes[0] }));
     }
 
 }