The difference between the two include methods. (Why go wrong, see for yourself.)

Include Q:
Why <jsp:include page= "Aa.txt"/> Not to be displayed? But you can use <%@ include file= "Aa.txt"%>?

For:
The two include are contained in a different way.
The former is the inclusion of HTML after the AA.TXT is processed through the server.
The latter is the first to include the file in, and then processing.
Therefore, if you use the former, you must ensure that the JSP statements in the file are correct. All variable definitions are independent.
If this is the latter, you can use external variables defined in AA.TXT before the include it.
There is a difference between the two, that is, the former is dynamically updated, that is to say AA.TXT if a variable occurs, all files containing it will change. And the latter, only to be able to see all the AA.TXT files first changed, recompile can be seen the new effect.