/**
   * Process listuser from server
   *
   * @param doc
   */
  private void _listuser(Document doc) {
    StringBuffer userlist = new StringBuffer();

    Element root = doc.getRootElement();
    Element list = root.getChild("listuser");
    List users = list.getChildren("user");
    Iterator i = users.iterator();
    while (i.hasNext()) {
      userlist.append(((Element) i.next()).getText());
      userlist.append("\n");
    }
    sendMessage(SERVER, "Users: \n" + userlist);
  }
  /**
   * Process listgroup from server
   *
   * @param doc
   */
  private void _listgroup(Document doc) {
    StringBuffer grouplist = new StringBuffer();

    Element root = doc.getRootElement();
    Element list = root.getChild("listgroup");
    List groups = list.getChildren("group");
    Iterator i = groups.iterator();
    while (i.hasNext()) {
      Element temp = (Element) i.next();
      grouplist.append(temp.getChild("name").getText());
      grouplist.append("\t");
      grouplist.append(temp.getChild("description").getText());
      grouplist.append("\n");
    }
    sendMessage(SERVER, "Groups: \n" + grouplist);
  }