private RouteNodeInstance determineStartNode(
     Collection<RouteNodeInstance> activeNodes, MovePoint movePoint)
     throws InvalidActionTakenException {
   RouteNodeInstance startNodeInstance = null;
   for (RouteNodeInstance nodeInstance : activeNodes) {
     if (nodeInstance.getName().equals(movePoint.getStartNodeName())) {
       if (startNodeInstance != null) {
         throw new InvalidActionTakenException(
             "More than one active node exists with the given name:  "
                 + movePoint.getStartNodeName());
       }
       startNodeInstance = nodeInstance;
     }
   }
   if (startNodeInstance == null) {
     throw new InvalidActionTakenException(
         "Could not locate an active node with the given name: " + movePoint.getStartNodeName());
   }
   return startNodeInstance;
 }
 private String displayMovePoint(MovePoint movePoint) {
   return "fromNode="
       + movePoint.getStartNodeName()
       + ", stepsToMove="
       + movePoint.getStepsToMove();
 }