/** Convert the model into a ChangeSet. */
  private ChangeSet asChangeSet() {

    // empty diff so changes will effectively all be create
    ModelDiff diff = new ModelDiff();
    diff.compareTo(model);

    List<Object> createChanges = diff.getCreateChanges();

    // put the changes into a ChangeSet
    ChangeSet createChangeSet = new ChangeSet();
    createChangeSet.getChangeSetChildren().addAll(createChanges);
    return createChangeSet;
  }