Java jsp taglib

Question

I frequently saw links to "external tag libraries" in jsp Ex:

<%@ taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql"%>

But I couldn't find answers to these questions:

• Does use a tag library from an external web location?
  • Does it query that location every time the tag is used?
  • Does it download it only once?
    • when does the download happen?
• Can I create my own tag library, and provide a similar external link to others?

Please edit this question if it's wrong, I never really asked questions of this type

Answer 1

Please refer bold replies

• Does use a tag library from an external web location? No
  • Does it query that location every time the tag is used? No
  • Does it download it only once? No download so no query
    • when does the download happen? Download never happens
• Can I create my own tag library, and provide a similar external link to others? Yes

The uri you see the JSP page, is actually referenced from web.xml file, refer to jsp-config.

Answer 2

A tag library is part of the application, no download is happening at runtime. The URL you see on the JSP page is just a namespace URI to bind the prefix used on the page to the tag library.

Yes, you can create your own tag library.