Index: /trunk/autoquest-core-usability-evaluation/src/main/java/de/ugoe/cs/autoquest/usability/util/PatternsVisitorUtil.java
===================================================================
--- /trunk/autoquest-core-usability-evaluation/src/main/java/de/ugoe/cs/autoquest/usability/util/PatternsVisitorUtil.java	(revision 1163)
+++ /trunk/autoquest-core-usability-evaluation/src/main/java/de/ugoe/cs/autoquest/usability/util/PatternsVisitorUtil.java	(revision 1164)
@@ -21,4 +21,5 @@
 import de.ugoe.cs.autoquest.tasktrees.treeifc.ITask;
 import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskModel;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.IUserSession;
 import de.ugoe.cs.autoquest.tasktrees.treeimpl.TaskFactory;
 
@@ -44,6 +45,6 @@
      * @return
      */
-    public static ITaskModel createTaskModelFromNode(ITask task) {
-        return new TaskFactory().createTaskTree(task);
+    public static ITaskModel createTaskModelFromUserSessions(List<IUserSession> userSessions) {
+        return new TaskFactory().createTaskModel(userSessions);
     }
     
@@ -57,5 +58,5 @@
      */
     public static ITask firstNodeOf(List<ITask> tasks) {
-        return Iterables.getFirst(tasks, new NullNode());
+        return Iterables.getFirst(tasks, new NullTask());
     }
 
@@ -69,5 +70,5 @@
      */
     public static ITask lastNodeOf(List<ITask> tasks) {
-        return Iterables.getLast(tasks, new NullNode());
+        return Iterables.getLast(tasks, new NullTask());
     }