@Override
  protected void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    String name = request.getParameter("name");
    String phone = request.getParameter("phone");

    try {
      if (name != null && name.length() > 0 && phone != null && phone.length() > 0) {
        if (request.getParameter("add") != null) {
          addUser(name, phone);
        } else if (request.getParameter("update") != null) {
          updateUser(name, phone);
        } else if (request.getParameter("delete") != null) {
          removeUser(name, phone);
        }
      }
      listAll(request, response);
    } catch (Exception e) {
      throw new ServletException(e);
    }
  }
The view data store.
<code>null</code> indicates that the view properties should be used instead of the data store.
ambari-views/examples/phone-list-view/src/main/java/org/apache/ambari/view/phonelist/PhoneListServlet.java