JSP - The taglib Directive


The JavaServer Pages API allows you to define custom JSP tags that look like HTML or XML tags and a tag library is a set of user-defined tags that implement custom behavior.

The taglib directive declares that your JSP page uses a set of custom tags, identifies the location of the library, and provides a means for identifying the custom tags in your JSP page.

The taglib directive follows the following syntax:

<%@ taglib uri="uri" prefix="prefixOfTag" >

Where the uri attribute value resolves to a location the container understands and the prefix attribute informs a container what bits of markup are custom actions.

You can write XML equivalent of the above syntax as follows:

<jsp:directive.taglib uri="uri" prefix="prefixOfTag" />

When you use a custom tag, it is typically of the form <prefix:tagname>. The prefix is the same as the prefix you specify in the taglib directive, and the tagname is the name of a tag implemented in the tag library


For example, suppose the custlib tag library contains a tag called hello. If you wanted to use the hello tag with a prefix of mytag, your tag would be <mytag:hello> and it will be used in your JSP file as follows:

<%@ taglib uri="http://www.example.com/custlib" prefix="mytag" %>

We would be able to call another piece of code using <mytag:hello>. We will see how to develop our custom tags and how to use them in JSP - Custom Tags tutorial.