display contents on the same page by selecting a radio button

Bill Amount Rs.<input type="text" name="amm"/>
    Bill Status:
    Pending<input type="radio" name="bill_status " value="due" />
        Received<input type="radio" name="bill_status" value="received"  />
    <%
String s=request.getParameter("bill_status");
if(s.equalsIgnoreCase("due"))
{   
%>
Due Date<input type="date" name="date"/>
<% 
}
%>

i want if i click on pending then the due date text field should be displayed on the same page under the radio button