<jsp:forward ...> not acting the way it should.

[Swagato Bhatta]

I m just practicing and came across this about jsp:forward. I wrote few beans (employee.java, person.java)...Those are fine.

In Index file (index.jsp) , request.getParameter("empID") is null here as I hoped it would be.
index.jsp

   <jsp:include page="welcome.jsp" >
            <jsp:param name="subtitle" value="${param.name}" />
        </jsp:include>

        request.getParameter("empID") " <% out.println(request.getParameter("empID")) ; %> "

        <form action="chosing.jsp" method="post">
            <p>name: <input type="text" name="name"></p>
            <p>ID#: <input type="text" name="empID"></p>
            <p>Car
                <select name="select" id="select">
                    <option value="honda">Honda</option>
                    <option value="toyota">Toyota</option>
                </select>
            </p>
                <input type="submit" />
        </form>

After clicking submit button, it goes to chosing.jsp.

In index.jsp, if I do not enter any data in the forms, then I hoped that I will get null for empID. However I do not.
I even tried using different empID values such as 111 and checked empID. But it is not working.

In short, it is not forwarding as I hoped it would.

In chosing.jsp

	<jsp:include page="welcome.jsp" >
            <jsp:param name="subtitle" value="${param.name}" />
        </jsp:include>

        <% if (request.getParameter("empID") == "111") {%>
            <jsp:forward page="another.jsp" />
        <% }%>
	<br>request.getParameter("empID") " <% out.println(request.getParameter("empID")) ; %> "
        <br>My name is again: ${param.name}
        <br>Employee ID is ${param.empID}
        <br>Employee Car is ${param.select} <br>

ok here welcome.jsp

        Welcome ${param.subtitle} to my JSP Page <br>

Why does it not come here when I do not put any inputs or use 111 for empID? Another.jsp

        <h1>Another Page!</h1>

[Christophe Verré]

Did you try to check for an empty string ?

if (request.getParameter("empID") == "111")

You must have forgotten how to compare String variables (SCJP).

[Swagato Bhatta]

Christophe Verré wrote:Did you try to check for an empty string ?

if (request.getParameter("empID") == "111")

You must have forgotten how to compare String variables (SCJP).

Is it going to be empty string or null string or " "?

[Christophe Verré]

Is it going to be empty string or null string or " "?

Why don't you check it ?

[Swagato Bhatta]

Christophe Verré wrote:

Is it going to be empty string or null string or " "?

Why don't you check it ?

Thank you for the hints. I spent a whole evening until midnight on this . grrr...

Yeep I have forgotten about Strings JAVA I think. How could I in such short time? blah

ANyway, I fixed it. thanks. I should have used the equals method as what I wanted is too check to make sure that two string vales are same not the two exact string objects..

[Swagato Bhatta]

I think I am getting string with "" for not inputing any data in the form. Is that an empty string or string with no whitespace. I mean string with no contents and whitespace is empty right?

I assumed that I would get null string. The assumption was wrong

Secondly, I forgot about == and .equals

[Christophe Verré]

I assumed that I would get null string. The assumption was wrong

I always forget about it too.

Secondly, I forgot about == and .equals

You'll never forget it again now

[Swagato Bhatta]

Christophe Verré wrote:

I assumed that I would get null string. The assumption was wrong

I always forget about it too.

Secondly, I forgot about == and .equals

You'll never forget it again now

Thanks. But how do I check to make sure that the user has atleast inputed a value ? The value can be anything other than whitespace. How Do I do this?

request.getParameter("empID").equals (" ") only checks for one whitespace. I want to make sure that doesnt matter how many whitespaces the user puts, I still check to make sure there is something else other than whitespace?

[Christophe Verré]

request.getParameter("empID") == null || "".equals(request.getParameter("empID").trim())

If you'd use EL instead of scriptlets, you could use the empty operator instead, with JSTL's c:if tag.

[Swagato Bhatta]

Christophe Verré wrote:request.getParameter("empID") == null || "".equals(request.getParameter("empID").trim())

If you'd use EL instead of scriptlets, you could use the empty operator instead, with JSTL's c:if tag.

Thanks...

I am just learning the JSTL :-)