This Java tips illustrates an example of a include a file in a JSP page. To include an HTML or JSP fragment in a JSP file, the include directive is used. The effect is essentially equivalent to replacing the directive with the contents of the included file.

The include file specified by include directive is always relative to the file containing the include directive. For example, if a file A.jsp includes dir/B.jsp which in turn includes C.jsp, C.jsp is assumed to be in the directory dir.

This example includes a file called relativeFragment.jsp which is located in the same directory as the current file:

  <%@ include file="relativeFragment.jsp" %>

This example includes a file called /absoluteFragment.jsp which is located relative to the web application's root:

 <%@ include file="/absoluteFragment.jsp" %>

At the time the main JSP page is accessed, the include directive permanently captures the current contents of an included file. Changes to the included file will not affect the results of the main JSP page. If the application depends on capturing the contents of the included file at the time of each request, then an include action should be used.

These examples demonstrate how to use an include action to dynamically include the contents of a relative or absolute fragment at every request:

 <jsp:include page="relativeDynFragment.jsp" />
    <jsp:include page="relativeDynFragment.html" />
    <jsp:include page="/absoluteDynFragment.jsp" />
    <jsp:include page="/absoluteDynFragment.html" />

It is also possible to dynamically choose the file to include. This example determines the file to include from a request parameter:

  <jsp:include page='<%= request.getParameter("incFile") %>' />