In JavaServer Pages technology, actions are elements that can create and access programming language objects and
affect the output stream.A custom action is invoked by using a custom tag in a JSP page.
A tag library is a collection of custom tags.
Some features of custom tags are:
* They can be customized via attributes passed from the calling page.
* They have access to all the objects available to JSP pages.
* They can modify the response generated by the calling page.
How to declare TagLibrary in Jsp :
Tag libraries are declared by using the <%@taglib %> directive of the JSP.
<%@taglib prifix="nameWhatever" uri="/WEB-INF/tldDirectory/tldName.tld" %>.
Attributes of the taglib directive are as follows:
uri: This is the attribute of the taglib directive in JSP that contains the absolute and relative URIs for the TLD
(Tag Library Descriptor) file which is with the ".tld" extension. This attribute must have the value as Tag
Library Descriptor (TLD).
prefix: This is the attribute of the taglib directive in JSP that is used for naming for the identification of the tag.
You can say simply that this attribute of the taglib directive contains the name of the specified Tags or
the TLDs for using in your JSP code easily and in efficient manner.
tagdir: This is also a type of the taglib directive in JSP that is used for specifying your customized tags.
These customized tags are made by specifying all the action in a file that must have the ".tag" or the ".tld" extension.
This is the used in the place of the uri attribute of the taglib directive of JSP.
For more information and example on Taglibrary in Jsp visit to :http://www.roseindia.net/jstl/