What is the difference between and ? [duplicate]

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In one reusable piece of code I use the directive <%@include file="reuse.html"%> and in the second I use the standard action <jsp:include page="reuse.html" />.

Let the code in the reusable file be:

<html>
<head>
    <title>reusable</title>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
    <img src="candle.gif" height="100" width="50"/> <br />
    <p><b>As the candle burns,so do I</b></p>
</body>

After running both the JSP files you see the same output and think if there was any difference between the directive and the action tag. But if you look at the generated servlet of the two JSP files, you will see the difference.

Here is what you will see when you use the directive:

out.write("<html>\r\n");
out.write("    <head>\r\n");
out.write("        <title>reusable</title>\r\n");
out.write("        <meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\">\r\n");
out.write("    </head>\r\n");
out.write("    <body>\r\n");
out.write("        <img src=\"candle.gif\" height=\"100\" width=\"50\"/> <br />\r\n");
out.write("        <p><b>As the candle burns,so do I</b></p>\r\n");
out.write("    </body>\r\n");
out.write("</html>\r\n");

And this is what you will see for the used standard action in the second JSP file :

org.apache.jasper.runtime.JspRuntimeLibrary.include(request, response, "reusable.html", out, false);

So now you know that the include directive inserts the source of reuse.html at translation time, but the action tag inserts the response of reuse.html at runtime.

If you think about it, there is an extra performance hit with every action tag (<jsp:include>). It means you can guarantee you will always have the latest content, but it increases performance cost.

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