Fixed DNF position handling

- DNF position is now "-"
- If boat DNFs during leg, other boats' rankings are updated to remain accurate
#story[15]

src/main/java/seng302/Model/BoatInRace.java

@@ -248,7 +248,7 @@ public class BoatInRace extends Boat {
         return position;
     }
 
-    public void setPosition(int position) {
-        this.position.set(Integer.toString(position + 1));
+    public void setPosition(String position) {
+        this.position.set(position);
     }
 }

src/main/java/seng302/Model/Race.java

@@ -174,7 +174,7 @@ public abstract class Race implements Runnable {
 
     private boolean doNotFinish() {
         Random rand = new Random();
-        return rand.nextInt(100) < 1;
+        return rand.nextInt(4) < 1;
     }
 
     /**
@@ -262,8 +262,21 @@ public abstract class Race implements Runnable {
                 boat.setDistanceTravelledInLeg(boat.getDistanceTravelledInLeg());
             }
             //Update the boat display table in the GUI to reflect the leg change
+            updatePositions();
+        }
+    }
+
+    /**
+     * Update position of boats in race, no position if on starting leg or DNF.
+     */
+    private void updatePositions() {
         FXCollections.sort(startingBoats, (a, b) -> b.getCurrentLeg().getLegNumber() - a.getCurrentLeg().getLegNumber());
-            boat.setPosition(startingBoats.indexOf(boat));
+        for(BoatInRace boat: startingBoats) {
+            if(boat != null) {
+                boat.setPosition(Integer.toString(startingBoats.indexOf(boat) + 1));
+                if (boat.getCurrentLeg().getName().equals("DNF") || boat.getCurrentLeg().getLegNumber() == 0)
+                    boat.setPosition("-");
+            }
         }
     }