java+js+date

in js:

var startDate=document.getElementById("startDate").value;
var endDate=document.getElementById("endDate").value;

in jsp:

<input type="hidden" name="startDate" id="startDate" value="<%=request.getAttribute("startDate") %>"/>
<input type="hidden" name="endDate" id="endDate" value="<%=request.getAttribute("endDate") %>"/>

in java:

String startDate=(String)request.getParameter("startDate");
String endDate=(String)request.getParameter("endDate");
request.setAttribute("startDate", startDate);
request.setAttribute("endDate",endDate);