Question

I have a header.jsp that I want to include in multiple pages. The header page has three links in it. I am using css to indicate to the user which page they are on at any given point. Here is the code for header.html:

<ul>
    <%-- Check for the activeState parameter to decide which css to use --%>
    <c:choose>
        <c:when test='${requestScope.activeState == "home"}'>
            <li><a href="index.jsp" class="active"><span>Home</span></a></li>
        </c:when>
        <c:otherwise>
            <li><a href="index.jsp"><span>Home</span></a></li>
        </c:otherwise>
    </c:choose>

    <c:choose>
        <c:when test='${requestScope.activeState == "about"}'>
            <li><a href="about.jsp" class="active"><span>About Us</span></a></li>
        </c:when>
        <c:otherwise>
            <li><a href="about.jsp"><span>About Us</span></a></li>
        </c:otherwise>
    </c:choose>

    <c:choose>
        <c:when test='${requestScope.activeState == "contact"}'>
            <li><a href="contact.jsp" class="active"><span>Contact Us</span></a></li>
        </c:when>
        <c:otherwise>
            <li><a href="contact.jsp"><span>Contact Us</span></a></li>
        </c:otherwise>
    </c:choose>
</ul>

This is what the index.jsp file calls:

<jsp:include page="header.jsp">
    <jsp:param value="home" name="activeState"/>
</jsp:include>

This does not work. Six links are showed in the index.html page. Three with css and three without css. Here is what the source looks like for the index.html page:

<c:choose>
    <c:when test='false'>
        <li><a href="index.jsp" class="active"><span>Home</span></a></li>
    </c:when>
    <c:otherwise>
        <li><a href="index.jsp"><span>Home</span></a></li>
    </c:otherwise>
</c:choose>

<c:choose>
    <c:when test='false'>
        <li><a href="about.jsp" class="active"><span>About Us</span></a></li>
    </c:when>
    <c:otherwise>
        <li><a href="about.jsp"><span>About Us</span></a></li>
    </c:otherwise>
</c:choose>

<c:choose>
    <c:when test='false'>
        <li><a href="contact.jsp" class="active"><span>Contact Us</span></a></li>
    </c:when>
    <c:otherwise>
        <li><a href="contact.jsp"><span>Contact Us</span></a></li>
    </c:otherwise>
</c:choose>

I also tried to get the activeState parameter using the param.activeState instead of requestScope.activeState. No change in behavior. Can somebody explain what is going on?

Answer 1

If you see the JSTL tags unparsed in the HTML source, then it means that either the JSTL taglib isn’t been declared in top of JSP as follows

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

or that JSTL isn’t installed at all. Download and install it as per the instructions in our JSTL wiki page.