I have a requirement that i need to save the value of a variable. My problem is that i need to send a value from an webpage to servlet where the value of the variable is null first time but when i slect a value from the select box it gooes to the servlet and it is going with the value but my problem is here i need to refesrh the page after selecting the value. so now when i am doing that the value becomes again zero and the operation is not happening can i save the value of the variable after selecting some values from the selection ??
here is my code..
<body>
Select Country:
<select id="country">
<option>Select Country</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
<input type="button" value="Reload page" onclick="reloadPage()">
</body>
<script>
function reloadPage(){
location.reload();
}
</script>
<script>
$(document).ready(function() {
$('#country').change(function(event) {
var $country=$("select#country").val();
$.get('JsonServlet',{countryname:$country},function(responseJson) {
var $select = $('#states');
$select.find('option').remove();
$.each(responseJson, function(key, value) {
$('<option>').val(key).text(value).appendTo($select);
});
});
});
});
</script>
and this is my servlet
public class JsonServlet extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
PrintWriter out = response.getWriter();
String value = request.getParameter("countryname");
System.out.println("comes from ajax" + value);
JsonGenerator generator = new JsonGenerator();
Entry entry = null;
if (value != null) {
HttpSession session = request.getSession();
session.setAttribute("value", value);
entry = generator.aMethod2Json(value);
Gson g = new Gson();
response.setContentType("application/json");
response.setCharacterEncoding("UTF-8");
response.getWriter().write(g.toJson(entry));
} else {
entry = generator.aMethod2Json("1");
Gson g = new Gson();
response.setContentType("application/json");
response.setCharacterEncoding("UTF-8");
response.getWriter().write(g.toJson(entry));
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP
* <code>GET</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP
* <code>POST</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}