Tags are Java classes. There are no implicit variables in Java classes.
JSPs, on the other hand, must first run through a translator before becoming servlets, which are Java classes. Implicit variables are simply words that the JSP translator understands - it knows how to turn them into meaningful servlet code.
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Joined: Sep 15, 2005
I think you guys are talking about the tag handler classes, which are Java classes. But the question I asked is about a tag file, a jsp file renamed with .tag or .tagx extension.
A Tag File is not the same as a JSP page. It is a JSP fragment. Some of the differences between Tag Files and JSP pages are the directives they use. Tag Files do not use the Page directive, but add three more directives - variable, attribute and tag. Also, when a Tag File is used in a JSP page, its body cannot have any scripting elements, just like Simple Tags. Similarly, because of the internal (web container) implementation of Tag Files, they share more in common with Simple Tags than Classic Tags. Hence, they have access to the JspContext (like Simple Tags) instead of PageContext (like Classic Tags) implicit object.