Re: How pass a form parameter value to a same jsp file?

From: jajoo (jivkoto_at_abv.bg)
Date: 01/23/04 

Date: 23 Jan 2004 02:44:42 -0800

Hi Ricky,
I think that you doing it right except that: When you first load the
jsp, this code request.getParameter("sort"); whill return null because
at the first load you do not have sort parameter. So sort1=null.
Because sort1=null sort1.equals("Asset_Number") will return
NullPointerException.

You should do this:
1)First way - to check if sort1==null

<% String sort1=request.getParameter("sort");
    String i=" ";
    if(sort1!=null){ // you should check if sort == null
        if (sort1.equals("Asset_Number"))
        i="Asset_Number";
        else if(sort1.equals("Description"))
        i="Description";
        else
        i="Type";
    }else{
        i="Type";
    }
%>

2)Second way use "Some string".equals(sort1)- if sort1==null no
Exception trown
<% String sort1=request.getParameter("sort");
    String i=" ";
        if ("Asset_Number".equals(sort1)) i="Asset_Number";
        else if("Description".equals(sort1)) i="Description";
        else
        i="Type";
%>

I think that both ways solve your problem.
Zhivko Mitrev