null value in request

[Eric Sexton]

I have an action class in struts with the following code:

  
String numOfSsns = (newAddSsn.getAddSSNNeed() + "");
System.out.println("The value passed from the select is: " + numOfSsns);
aRequest.setAttribute("numOfSsns",numOfSsns);
        return aMapping.findForward("success");

The numOfSsns variable is getting populated fine. Anyhow the forward gets moved on to a jsp that has the following code:

  
<%
if ((String)request.getParameter("numOfSsns") != null)
{
String ssns = (String)request.getParameter("numOfSsns");
System.out.println("The number of SSNs to display is: " + ssns);
}
else
{
System.out.println("There was no value");
}
%>

I am always getting a null value in the request, so the if statement is failing. What am I not getting right here?

[Jaime Garcia]

you are using:
request.setAttribute("numOfSsns",numOfSsns);
then forward a jsp and:
request.getParameter("numOfSsns");

getParameter will try to find it from a GET or POST method. You need to retrive it with getAttribute("numOfSsns"); not getParameter
Hope this helps.

[Eric Sexton]

D'oh! You da man! Thanks for the effort.

[Eric Sexton]

Let me ask a follow up. Why are there both getParameters and getAttributes? How are they different?

[David O'Meara]

Parameters are read-only and represent the information sent from the client.
Attributes are a place for you maintain your own information in the request context.
Parameters are slightly different to the description given above since you can also define them when using the forward/include JSP tags, but as far as that JSP is concerned they are read-only.
Dave.