JSP include directive, jsp:include action, relative vs. absolute paths

Question

I am doing some basic templating in my JSP-based webapp. For example, I want to have a standard header and footer (basic HTML) that I pull into each of my JSPs.

My content JSP is at /WEB-INF/jsp/home.jsp, and I have template JSPs at /WEB-INF/jsp/template/, such as /WEB-INF/jsp/template/Body-Footer.jsp.

So now, within home.jsp, I want to pull in my template files. First, I try the jsp:include action:

<jsp:include page="template/Body-Footer.jsp"></jsp:include>

It generates the error javax.servlet.ServletException: File "/template/Body-Footer.jsp" not found

Strange to me, considering that Eclipse says that the path is valid.

Okay, so then I switch to the include directive:

<%@ include file="template/Body-Footer.jsp" %>

This works just fine, pulls in my footer HTML.

But why does the jsp:include not work? After some experimentation, I find that putting in the absolute path does get it to work:

<jsp:include page="/WEB-INF/jsp/template/Body-Footer.jsp"></jsp:include>

Now it works fine, no errors.

So here's my question: why? Why do I (apparently) need to use an absolute path with the jsp:include action, but not with the include directive?

Solution

/WEB-INF/jsp/template/Body-Footer.jsp is not an absolute path. Its also a relative path. The problem is that template/Body-Footer.jsp is an incomplete relative path, whereas the other is complete. That is, the paths are relative to your app path. Since /WEB-INF/ is under your app path, you have to include it. Absolute path means like C:/program files/tomcat/webapps/yourapp/WEB-INF/jsp/template/Body-Footer.jsp

Comments

[Luiggi Mendoza]

The other path is absolute regarding the application context URL.

[developerwjk]

Its absolute RELATIVE to the application context, thus not really absolute at all. There's a clear confusion in terminology going on. Of course your relative paths have to be complete, otherwise, how would they work?

[Luiggi Mendoza]

That's what I've said. I don't negate the fact that they are relatives paths after all.

[Matt Mc]

This is helpful, thanks. However, on your recommendation of putting the JSPs outside of the WEB-INF folder, maybe I missed it but I couldn't see something in that link that recommended that. In support of putting the JSPs in WEB-INF, we have this: stackoverflow.com/questions/6825907/why-put-jsp-in-web-inf

[Christopher Schultz]

Placing your JSP files under /WEB-INF/ is a common practice which "hides" the pages from direct-requests, allowing you to ensure that all requests are directed e.g. through a controller or other mechanism that protects your scripts from casual browsing.