JSP Servlet getParameter() giving null

Question

In the servlet I am trying to get the value of the submit button in the form below using

Servlet code:

String addGifts = request.getParameter("addGifts");

This code gives me attribute addGifts as null. The form is below. The value of temp.get(0) is a (Long) Object.

JSP form:

<%
    int i = gifts.size();
    System.out.println("gifts.size() = " + i);
    int j = 0;
    while (j < i) {
        ArrayList temp = new ArrayList();
        temp = gifts.get(j);
        System.out.println("Gift Id: " + temp.get(0));
        out.println("<tr>");
        out.println("<td>" + temp.get(1) + "</td>");
        out.println("<td>" + temp.get(2) + "</td>");
        out.println("<td>" + temp.get(3) + "</td>");
        out.println("<td><form method=\"POST\" action=\"gift-add\">");
        out.println("<button type=\"submit\" name=\"addgift\" value=\"" + temp.get(0) + "\">Redemm</button>");
        out.println("</form></td>");
        out.println("</tr>");
        j++;
    }
    //System.out.println("<input class=\"text\" value=\"Enter Page\">");
%>

Any ideas why the attribute addGifts is null?

Suresh Atta · Answer 1 · 2013-10-28T14:42:03.470

2

You have a small typo. Your name in code is

name=\"addgift\"  ----->  addgift

and you are using

   request.getParameter("addGifts"); --->  addGifts

Look at the capital G.

So, both the strings must be same. They are case sensitive.

edited Oct 28 '13 at 14:42

answered Oct 28 '13 at 14:36

Suresh Atta

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You mean `name=\"addGifts\"`, otherwise it will still be `null` for being different `String`s. – Luiggi Mendoza Oct 28 '13 at 14:39
Wow. Didn't notice that. Thanks so much! – Darve Oct 28 '13 at 14:42
@Darve. Happens sometime. Happy coding :) – Suresh Atta Oct 28 '13 at 14:46

score 0 · Answer 2 · answered Oct 28 '13 at 14:37

0

It because of typo, try replacing following code in servlet. "G" should be in small case

String addGifts = request.getParameter("addgifts");

answered Oct 28 '13 at 14:37

Dark Knight

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score 0 · Answer 3 · answered Oct 28 '13 at 14:37

0

Change addGifts to addgift.

Always check for uppercase ;D

answered Oct 28 '13 at 14:37

Lukas Warsitz

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score 0 · Answer 4 · edited May 23 '17 at 12:21

It is null since there's no component with name "addGifts" inside the <form> to send to the server.

By the way, it is a bad idea to use the button as the holder of your parameter. At least use a hidden field

<input type="hidden" name="addGifts" value="..." />
<button type="submit" name="addgift" value="Redemn" />

Also, it is a bad idea to use scriptlets in JSP. Try to keep it clean of Java code.

More info:

How to avoid Java code in JSP files?

JSP Servlet getParameter() giving null

4 Answers4