Why does tomcat includes *.jspf fragments as static text while jetty processes them dynamically?

Question

I was developing my toy project using jetty maven plugin and executing goal jetty:run. Now i decided to check how it works on tomcat.

I have two jspf fragments: header.jspf and footer.jspf inside of WEB-INF/jspf/ containing common code for all of my jsp pages. I include fragments like this:

<jsp:include page="WEB-INF/jspf/header.jspf" flush="true">
    <jsp:param name="pageTitle" value="Customer registration"/>
</jsp:include>

Jetty processed them like dynamic fragments, while tomcat processed them as static text, that's why i can see:

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

in the beginning of web page in my browser. The issue with tomcat was solved easily by renaming: *.jspf into *.jsp. The question is: why different servlet containers act differently? I performed tests on tomcat 8/9 and jetty 9.3.7.

Answer 1

Add a new file extension to mywebapp/WEB-INF/web.xml file. Why do Tomcat does not do this default I don't know. Defaults are in conf/web.xml file you could edit it as well. Another servlet engine may use different servlet name so this is Tomcat only solution.

<servlet-mapping>
    <servlet-name>jsp</servlet-name>
    <url-pattern>*.jsp</url-pattern>
    <url-pattern>*.jspf</url-pattern>
</servlet-mapping>