I have a jsp page with a form. form contains a textfield, once the user submits the form, i want jsp scriptlet to get the value of the user input and carry out processing on it within the same page and give a result. problem is the first time the page is loaded, there is an error in the request.getParameter() statement since no form has yet been submitted i guess .... if i use another page ... it works ... but i want to display the information in the same page ... thanks
if (request.getParameter("Submit")!=null) so that your page does not show any error for the first time
Why you check the submit value ?
I think we don't need to check the Button value in this condition. The error will not occur on the submit(button) value because i retrieved textField value in request.getParameter("MyText") so i already applied that (if condition) in above post to checking the null value.. for the first time loading.
if (request.getParameter("Submit") != null) makes sure the page has already been submitted. So placing getParameter() for other fields inside this condition will not give you any errors before the page is submitted.
If you have one or two fields you can check for null values as you suggested but it will be difficult if you have more fields.