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Preface
Comment
Declaration
Expression
Scriptlet
EL Expression
Directives
Attribute Directive
Include Directive
Page Directive
Tag Directive
Taglib Directive
Variable Directive
Standard Actions
<jsp:attribute>
<jsp:body>
<jsp:element>
<jsp:doBody>
<jsp:forward>
<jsp:getProperty>
<jsp:include>
<jsp:invoke>
<jsp:output>
<jsp:plugin>
<jsp:root>
<jsp:setProperty>
<jsp:text>
<jsp:useBean>

Taglib Directive

Defines a tag library and prefix for the custom tags used in the JSP page.

JSP Syntax

<%@ taglib {uri="URI" | tagdir="/WEB-INF/tags[/subdir]+"} 
prefix="tagPrefix" %>

XML Syntax

None. Included in <jsp:root> and in any other XML element using the xmlns attribute instead:

<anyxmlelement xmlns:prefix="{uri | urn:jsptld:path | 	
      urn:jsptagdir:/WEB-INF/tags[/subdir]+}" >

Examples

<%@ taglib uri="http://www.jspcentral.com/tags" prefix="public" %>	
	
<public:loop>	
   ...	
</public:loop>

Description

The taglib directive declares that the JSP page uses custom tags, names the tag library that defines them, and specifies their tag prefix.

You must use a taglib directive before you use the custom tag in a JSP page. You can use more than one taglib directive in a JSP page, but the prefix defined in each must be unique.

Tutorials on creating custom tags are available at http://java.sun.com/products/jsp/taglibraries.html#tutorials.

Attributes

uri="URI"

The Uniform Resource Identifier (URI) that uniquely locates the TLD that describes the set of custom tags associated with the named tag prefix. A URI can be any of the following:
- A Uniform Resource Locator (URL), as defined in RFC 2396, available at http://www.hut.fi/u/jkorpela/rfc/2396/full.html
- A Uniform Resource Name (URN), as defined in RFC 2396
- An absolute or relative pathname
If the URI is a URL or URN, then the TLD is located by consulting the mapping indicated in web.xml extended using the implicit maps in the packaged tag libraries. If URI is pathname, it is interpreted relative to the root of the web application and should resolve to a TLD file directly, or to a JAR file that has a TLD file at location META-INF/taglib.tld.
tagdir="/WEB-INF/tags[/subdir]+"

Indicates this prefix is to be used to identify tag extensions installed in the /WEB-INF/tags/ directory or a subdirectory. An implicit tag library descriptor is used. A translation error must occur under any of these conditions:
- The value does not start with /WEB-INF/tags/.
- The value does not point to a directory that exists.
- If this attribute is used in conjunction with the uri attribute.
prefix="tagPrefix"

The prefix that precedes the custom tag name, for example, public in <public:loop>. Empty prefixes are illegal. If you are developing or using custom tags, you cannot use the tag prefixes jsp, jspx, java, javax, servlet, sun, and sunw, as they are reserved by Sun Microsystems.