/** {@inheritDoc} */
  public List<User> getPossibleResponsibles(BacklogItem bli) {
    Set<User> userSet = new HashSet<User>();

    // Get all enabled users
    userSet.addAll(userBusiness.getEnabledUsers());

    // Get all previous responsibles
    if (bli != null) {
      userSet.addAll(bli.getResponsibles());
    }

    // Create the list and sort it
    List<User> userList = new ArrayList<User>(userSet);
    Collections.sort(userList, new UserComparator());

    return userList;
  }
  /** {@inheritDoc} */
  public List<User> getAssignableUsers(Project project) {
    Set<User> userSet = new HashSet<User>();

    // Add all assigned users
    userSet.addAll(backlogBusiness.getUsers(project, true));

    // Add all enabled users
    userSet.addAll(userBusiness.getEnabledUsers());

    // Add the users to a list
    List<User> userList = new ArrayList<User>(userSet);

    // Sort the list
    Collections.sort(userList, new UserComparator());

    return userList;
  }