When Should You Use JSP Include Directives, Actions, or Tag Files?

Including Content in JSP: JSP Include Directive vs. JSP Include Action vs. Tag Files

Including Content using Directives and Actions

There are two ways to include content into a JSP page using directives and actions:

1) @include Directive:

<%@ include file="header.html" %>

This directive includes the content of the specified file statically during page translation. It is suitable for static content that does not change frequently.

2) Action:

<jsp:include page="header.jsp" />

This action includes the content of the specified JSP page dynamically during page request processing. It is used for content that changes often and depends on request information.

Tag Files: An Alternative for Content Reuse

Tag files are a different approach for content reuse in JSP. They allow you to define custom tags that encapsulate reusable content and logic. You can create a tag file by defining a JSP page with the following structure:

<%@ tag description="Description" pageEncoding="UTF-8"%>
<jsp:root>
    <!-- Custom tag content goes here -->
</jsp:root>

To use a tag file, you declare it in the main JSP page using a tag library directive:

<%@ taglib prefix="t" tagdir="/WEB-INF/tags" %>

You can then call the custom tag within your JSP page:

<t:mytag>
    <!-- Tag body content -->
</t:mytag>

Comparison: Tag Files vs. Includes

Tag files are not the same as includes. They offer a range of features that includes do not, including:

• Custom attributes for parameterization
• Return values to the calling page
• Communication between tags
• Variable sharing within nested tags

Conclusion

Use the right tool for the task:

• Use includes for static content that changes rarely.
• Use tag files for reusable content with dynamic or complex logic.

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