initial version of a json service getting the race states for all races of an event

java/com.sap.sailing.domain.shared.android/src/com/sap/sailing/domain/racelog/RaceLog.java

@@ -41,5 +41,9 @@ public interface RaceLog extends Track<RaceLogEvent> {
      * Remove a listener.
      */
     void removeListener(RaceLogEventVisitor listener);
-
+    
+    /**
+     * Checks if the race log is empty.
+     */
+    boolean isEmpty();
 }

java/com.sap.sailing.domain.shared.android/src/com/sap/sailing/domain/racelog/impl/RaceLogImpl.java

@@ -93,6 +93,11 @@ public class RaceLogImpl extends TrackImpl<RaceLogEvent> implements RaceLog {
         }
     }
 
+    @Override
+    public boolean isEmpty() {
+        return getFirstRawFix() == null;
+    }
+
     @Override
     public void addListener(RaceLogEventVisitor listener) {
         synchronized (listeners) {
@@ -124,5 +129,4 @@ public class RaceLogImpl extends TrackImpl<RaceLogEvent> implements RaceLog {
         ois.defaultReadObject();
         listeners = new HashSet<RaceLogEventVisitor>();
     }
-
 }