This is my jquery code
//jquery
<script>
$.post("dashboardcon", $("#date").serialize(), function(responseHtml) {
    $('#date').html(responseHtml); 
});
</script>
html
<form>
    Date :<br> <input id="date" type="text" name="date">
         <input type="submit" value="Submit">
</form>
servlet
@WebServlet("/dashboardcon")
public class dashboardCon extends HttpServlet {
    private static final long serialVersionUID = 1L;
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        JSONObject jObj = new JSONObject();
        try {
            JSONObject newObj = jObj.getJSONObject(request.getParameter("date"));
            System.out.println(newObj);
        } catch (JSONException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
 
     
    