Changed add listener return value

java/com.sap.sailing.domain/src/com/sap/sailing/domain/tracking/AbstractRaceTrackerBaseImpl.java

@@ -7,7 +7,6 @@ import java.net.MalformedURLException;
  * Base class for all {@link RaceTracker}s that must implement listener notifications
  */
 public abstract class AbstractRaceTrackerBaseImpl implements RaceTracker {
-
     private final RaceTrackerListeners listeners = new RaceTrackerListeners();
 
     /**
@@ -34,13 +33,12 @@ public abstract class AbstractRaceTrackerBaseImpl implements RaceTracker {
     }
 
     @Override
-    public void add(Listener listener) {
-        listeners.addListener(listener);
+    public boolean add(Listener listener) {
+        return listeners.addListener(listener);
     }
 
     @Override
     public void remove(Listener listener) {
         listeners.removeListener(listener);
     }
-
 }

java/com.sap.sailing.domain/src/com/sap/sailing/domain/tracking/RaceTracker.java

@@ -89,8 +89,9 @@ public interface RaceTracker {
      * Register a new RaceTracker.Listener for this race tracker.
      * 
      * @param newListener
+     * @return true if listener has been added
      */
-    void add(RaceTracker.Listener newListener);
+    boolean add(RaceTracker.Listener newListener);
 
     /**
      * Remove listener from racetracker