OnBlur() function and JSP

Question

Hello Everybody!
I'd like to knwo how can I use onBlur() function to make my SELECT form works without submit...
Pratically, I need that, when a use "blur" a voice in the firs SELECT form, the second SELECT change without making a submit.
The problem is that this JSP calls a Servlet that builds a bean, but the solution may be very simple, because I only need (if the user select a particular voice in the first SELECT) to inhibit the second and the third SELECT..
<form name="nuovo" action="TicketHandler" method="post">
<table >
<tr><td>
<b>Programma</b></td>
<td><select name="programma">
<%     dati_bean = bean.Dati_Programma_Ticket();          
     Iterator Idati_bean2 = dati_bean.iterator();
     while (Idati_bean2.hasNext()){
        SQLBean myBean = (SQLBean)Idati_bean2.next();           
          String programma = myBean.getParametro();
          %>
<option><%=programma%></option>
<%}
%>
</select></td></tr>
<tr><td>
<b>Relase</b></td>
<td><select name="relase">
<%     dati_bean = bean.Dati_Relase_Ticket();          
     Iterator Idati_bean3 = dati_bean.iterator();
     while (Idati_bean3.hasNext()){
        SQLBean myBean = (SQLBean)Idati_bean3.next();           
          String relase = myBean.getParametro();
          %>
<option><%=relase%></option>
<%}%>
</select></td></tr>
<tr><td>
<b>Modulo</b></td>
<td><select name="modulo">
<%     dati_bean = bean.Dati_Modulo_Ticket();          
     Iterator Idati_bean = dati_bean.iterator();
     while (Idati_bean.hasNext()){
        SQLBean myBean = (SQLBean)Idati_bean.next();           
          String modulo = myBean.getParametro();
          %>
<option><%=modulo%></option>
<%}
%>

Answer 1

I know there's a javascript way to build a dynamic drop down list, but I was ooking for a "merged" Javascript+Java JSP recursive example! ( I need 3 different dropdown recursively dependet the second from the first and the third from the second..)
anyone can helps?