Custom Tag Web XML Tag Lib : Custom Tag « JSP « Java Tutorial






  1. Java Tutorial
  2. JSP
  3. Custom Tag

HelloWorld.java

package beans;

import javax.servlet.http.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.util.*;

public class HelloWorld extends TagSupport
{
    public int doStartTag() throws JspException
    {
        try
        {
            JspWriter out = pageContext.getOut();
            HttpServletResponse response = (HttpServletResponse)pageContext.getResponse();
            out.write("Hello world!");
        }
        catch(Exception e)
        {   
            throw new JspException(e.getMessage());
        }
        return EVAL_PAGE;
    }
}

simple.tld

<!DOCTYPE taglib
  PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN"
   "http://java.sun.com/dtd/web-jsptaglibrary_1_2.dtd">

    <!-- a tab library descriptor -->
<taglib xmlns="http://java.sun.com/JSP/TagLibraryDescriptor">
  <tlib-version>1.0</tlib-version>
  <jsp-version>1.2</jsp-version>
  <short-name>Simple Tags</short-name>

  <tag>
    <name>HelloWorld</name>
    <tag-class>beans.HelloWorld</tag-class>
    <body-content>empty</body-content>
  </tag>
</taglib>

web.xml

<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE web-app
PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>

  <taglib>
      <taglib-uri>
         http://www.java2s.com/custom
      </taglib-uri>
      <taglib-location>
         /WEB-INF/tags/simple.tld
      </taglib-location>
  </taglib>
  <context-param>
    <param-name>javax.servlet.jsp.jstl.fmt.timeZone</param-name>
    <param-value>US/Central</param-value>
  </context-param>

  <context-param>
    <param-name>database-driver</param-name>
    <param-value>org.gjt.mm.mysql.Driver</param-value>
  </context-param>

  <context-param>
    <param-name>database-url</param-name>
    <param-value>
    jdbc:mysql://localhost/forum?user=forumuser</param-value>
  </context-param>

  <taglib>
    <taglib-uri>http://java.sun.com/jstl/fmt</taglib-uri>
    <taglib-location>/WEB-INF/fmt.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>http://java.sun.com/jstl/fmt-rt</taglib-uri>
    <taglib-location>/WEB-INF/fmt-rt.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>http://java.sun.com/jstl/core</taglib-uri>
    <taglib-location>/WEB-INF/c.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>http://java.sun.com/jstl/core-rt</taglib-uri>
    <taglib-location>/WEB-INF/c-rt.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>http://java.sun.com/jstl/sql</taglib-uri>
    <taglib-location>/WEB-INF/sql.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>http://java.sun.com/jstl/sql-rt</taglib-uri>
    <taglib-location>/WEB-INF/sql-rt.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>http://java.sun.com/jstl/x</taglib-uri>
    <taglib-location>/WEB-INF/x.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>http://java.sun.com/jstl/x-rt</taglib-uri>
    <taglib-location>/WEB-INF/x-rt.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>
    http://java.jeffheaton.com/taglib/jstl/forum</taglib-uri>
    <taglib-location>/WEB-INF/forum.tld</taglib-location>
  </taglib>

  <taglib>
    <taglib-uri>/tlt</taglib-uri>
    <taglib-location>/WEB-INF/taglib.tld</taglib-location>
  </taglib>
</web-app>

Jsp page with custom tag

<%@ taglib uri='http://www.java2s.com/custom' prefix='hw' %>

<html>
  <body>
    <hw:HelloWorld />
  </body>
</html>
  Download:  CustomTagWebXMLTagLib.zip( 1,067 k)




23.58.Custom Tag
23.58.1.Custom Tag Support
23.58.2.Custom Tag For Outputing Message To Console
23.58.3.Custom Tag For Iteration
23.58.4.Jars For Custom Tag Development
23.58.5.Custom Tag With Property
23.58.6.Custom Tag Web XML Tag Lib
23.58.7.Custom Tag To Insert Text
23.58.8.Custom Tag To Get Parameter From PageContext
23.58.9.Extends Tag Support DoEndTag
23.58.10.Reference Tag Using Tag Dir
23.58.11.Repeat Tag
23.58.12.Custom Tag For Shuffling Color
23.58.13.Custom Tag For Display message
23.58.14.Custom Tag Without TLD
23.58.15.Custom Tag With Attributes
23.58.16.Custom Tag Web URI Definition
23.58.17.Custom Tag Using Beans
23.58.18.Custom Tag Setup Environment
23.58.19.Custom Tag Set Bean Value
23.58.20.Custom Tag Dynamic Attributes
23.58.21.Custom Tag As Template
23.58.22.Custom Tag Accepting Fragments