JSP Tutorials - Herong's Tutorial Examples - Version 4.03, by Dr. Herong Yang
Tag Attributes Are Tag Object Properties
This section describes custom tag attributes, which are defined as tag object properties with setter methods.
The JSP tag extension facility maps each attribute encountered in a custom tag to a property of the same name in the tag object. So if you want to use an attribute in a custom tag, you must define a property in the tag class with the same name as the attribute. Here are the steps you need to follow to add an attribute to a custom tag:
1. Define a property in the tag class with the same name as the attribute name by adding a setter method and a getter method. This is the same way as defining a property in a JavaBean class.
2. Add an "attribute" element inside the "tag" element in your TLD file with the following syntax:
<tag> <name>tag_name</name> <tag-class>class_full_name</tag-class> <body-content>empty | jsp</body-content> <attribute> <name>attribute_name</name> <required>true | false</required> </attribute> </tag>
3. Add the attribute to the custom tag in your JSP page. Then the tag is processed, the setter method of the tag object will be called to pass the attribute value into the tag object.
Last update: 2012.
Table of Contents
JSP (JavaServer Pages) Overview
Tomcat 7 Installation on Windows Systems
Syntax of JSP Pages and JSP Documents
JavaBean Objects and "useBean" Action Elements
Managing HTTP Response Header Lines
Non-ASCII Characters Support in JSP Pages
Overview of JSTL (JSP Standard Tag Libraries)
►Tag Attributes Are Tag Object Properties
Setter Method Example - EchoTag.java
Value Type Conversion Example - AttValueTag.java
Accepting EL Expression Example
Passing Expression as String Example
Using jsp:attribute Action Elements