/**
   * Return the image used for the given node.
   *
   * @see org.eclipse.jface.viewers.ILabelProvider#getImage(java.lang.Object)
   */
  public Image getImage(Object element) {
    if (element instanceof Alias) {
      Alias alias = (Alias) element;

      for (User user : alias.getUsers())
        if (!user.getSessions().isEmpty()) return _activeAliasImage;
      return _inactiveAliasImage;
    }
    return _sessionImage;
  }