Index: /trunk/autoquest-plugin-uml/src/main/java/de/ugoe/cs/autoquest/plugin/uml/UMLUtils.java
===================================================================
--- /trunk/autoquest-plugin-uml/src/main/java/de/ugoe/cs/autoquest/plugin/uml/UMLUtils.java	(revision 1929)
+++ /trunk/autoquest-plugin-uml/src/main/java/de/ugoe/cs/autoquest/plugin/uml/UMLUtils.java	(revision 1930)
@@ -66,5 +66,4 @@
 import org.eclipse.uml2.uml.Property;
 import org.eclipse.uml2.uml.Region;
-import org.eclipse.uml2.uml.Relationship;
 import org.eclipse.uml2.uml.Slot;
 import org.eclipse.uml2.uml.StateMachine;
@@ -251,8 +250,6 @@
                                                           StateMachine stateMachine)
     {
-        System.out.println("foo");
         List<List<Transition>> matchingSequences =
             determineMatchingTransitionSequences(sequence, stateMachine);
-        System.out.println(matchingSequences.size());
 
         if (matchingSequences.size() != 1) {
@@ -375,6 +372,4 @@
         for (Iterator<Event> eventIterator = sequence.iterator(); eventIterator.hasNext();) {
             Event event = eventIterator.next();
-            System.out.println(event);
-            System.out.println(matchingSequences);
             if (matchingSequences == null) {
                 matchingSequences = new LinkedList<>();
@@ -783,16 +778,7 @@
                     CallEvent callEvent = (CallEvent) triggers.get(0).getEvent();
                     String transitionMethod = callEvent.getOperation().getName();
-
-                    Interface intface = callEvent.getOperation().getInterface();
-                    for (Relationship relationship : intface.getRelationships()) {
-                        for (Element element : relationship.getRelatedElements()) {
-                            if (element instanceof Component) {
-
-                            }
-                        }
-                    }
-
                     String transitionService =
                         interfaceServiceMap.get(callEvent.getOperation().getInterface());
+                    
                     if (eventMethod.equals(transitionMethod) &&
                         eventService.equals(transitionService))
@@ -801,4 +787,6 @@
                     }
                 }
+            } else {
+                throw new RuntimeException("only one trigger of type CallEvent per transition allowed: " + transition.getName());
             }