拳不离手、曲不离口 - Speak with your code, my friend, not your word.

jsp是如何处理它的元素的.

During the translation phase each type of data in a JSP page is treated differently. Static data is
transformed into code that will emit the data into the response stream. JSP elements are treated
as follows:
■ Directives are used to control how the web container translates and executes the JSP page.
■ Scripting elements are inserted into the JSP page’s servlet class. See Chapter 9, “Scripting in
JSP Pages,” for details.
■ Expression language expressions are passed as parameters to calls to the JSP expression
evaluator.
■ jsp:[set|get]Property elements are converted into method calls to JavaBeans
components.
■ jsp:[include|forward]elements are converted into invocations of the Java Servlet API.
■ The jsp:plugin element is converted into browser-specific markup for activating an applet.
■ Custom tags are converted into calls to the tag handler that implements the custom tag.