Mr. Hanna, Followed Your Advice On Custom Tag, Same Error Message

[JiaPei Jen]

Mr. Hanna, Thank you for taking a look at my code. My tag library descriptor file, csajsp-taglib.tld, was and is under
c:\bea\wlserver6.0sp1
\config\mydomain\applications\DefaultWebApp_myserver\WEB-INF
Pursuant to your comment, my web.xml file looks like:
<?xml version="1.0" ?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN" "http://java.sun.com/j2ee/dtds/web-app_2_2.dtd">
<web-app>
<taglib>
<taglib-uri>csajsp-taglib.tld</taglib-uri>
<taglib-location>/WEB-INF/csajsp-taglib.tld</taglib-location>
</taglib>
</web-app>
I typed http://localhost:7001/SimpleExample.jsp in the IE browser, and the error message is the same:
Parsing of JSP File '/SimpleExample.jsp' failed:
/SimpleExample.jsp(6): Could not parse deployment descriptor: java.io.IOException: cannot resolve 'csajsp-taglib.tld' into a valid tag library
probably occurred due to an error in /SimpleExample.jsp line 6:
<%@ taglib uri="csajsp-taglib.tld" prefix="csajsp" %>
Thu Apr 13 19:24:46 EDT 2000
I really don't know what to do. Please help.

[Phil Hanna]

JiaPei, just two more typos to fix in your csajsp-taglib.tld:
1. Remove the space after <! before DOCTYPE.
2. Remove the <urn></urn> line - there is no such element defined in the taglib DTD. It should be <uri></uri> (but you don't need to specify it at all).
I made those two changes and your example is working for me under Tomcat 4.0 beta 3.
------------------
Phil Hanna
Sun Certified Programmer for the Java 2 Platform
Author of :
JSP: The Complete Reference
Instant Java Servlets
Website: http://www.philhanna.com

[JiaPei Jen]

Mr. Hanna, I am glad to know that my very simple custom tag is working on your Tomcat. I followed your instructions:
1. delete the space between ! and DOCTYPE
2. delete <urn></urn>
and my web.xml is
<taglib>
<taglib-uri>csajsp-taglib.tld</taglib-uri>
<taglib-location>/WEB-INF/csajsp-taglib.tld</taglib-location>
</taglib>
I am still getting the same old message:

cannot parse the tag library descriptor file

when running this example on the WebLogic 6.0. I just don't know how to straighten out the problem. Very frustrating.

[maha anna]

JiaPei,
Did this procedure and able to view SimpleExample.jsp. Used Tomcat3.1 on win98. You can also try it.
1. Just create a "tag" dir under your web-appln root.
Example C:\jakarta-tomcat\webapps\MISApp\tags
Here "MISApp" is my web-appn contextName.
2. Copy these 3 file to this "tags" dir.
1) Jsp-Styles.css
2) csajsp-taglib.tld
3) SimpleExample.jsp
C:\jakarta-tomcat\webapps\MISApp\tags\SimpleExample.jsp
C:\jakarta-tomcat\webapps\MISApp\tags\Jsp-Styles.css
C:\jakarta-tomcat\webapps\MISApp\tags\csajsp-taglib.tld
4. Remove all your addtional lines you wrote in web.xml regard to this tag.
3. Just call from browser like this :
http://localhost/MISApp/tags/SimpleExample.jsp
or
http://localhost:8080/MISApp/tags/SimpleExample.jsp
I cut and paste the source also. You can use the same. Give it a try. I didn't make any changes in web.xml.
Meaning , didn't add any modification related to this tag/taglib.

---------------------------------------------------------------
//web.xml 
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN" "http://java.sun.com/j2ee/dtds/web-app_2_2.dtd">
<web-app>
<context-param>
      <param-name>webmaster</param-name>
      <param-value>[e-mail]</param-value>
      <description>
        The EMAIL address of the administrator to whom questions
        and comments about this application should be addressed.
      </description>
    </context-param>

    <display-name>Hello, World Application</display-name>
    <description>
This is a simple web application with a source code organization
based on the recommendations of the Application Developer's Guide.
    </description>
    <servlet>
        <servlet-name>AMSServlet</servlet-name>
        <servlet-class>MISApp.AMSServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>AMSServlet</servlet-name>
        <url-pattern>/AMSServlet</url-pattern>
    </servlet-mapping>
</web-app>
---------------------------------------------
//JSP-Styles.css
<STYLE TYPE="text/css">
<!--
BODY { background-color: #FDF5E6 }
A:hover { color: red }
H1 { color: #440000;
     text-align: center;
     font-family: Arial Black, Arial, Helvetica, sans-serif
}
H2 { color: #440000;
     text-align: left;
     font-family: Arial, Helvetica, sans-serif
}
H3 { color: #440000;
     text-align: left;
     font-family: Arial, Helvetica, sans-serif
}
UL { margin-top: 0;
     border-top-width: 0;
     padding-top: 0
}
DT { font-weight: bold;
}
PRE { font-size: 105%;
}
CODE { font-size: 105%; 
}
.TOC { font-size: 90%;
       font-weight: bold;
       font-family: Arial, Helvetica, sans-serif
}
TH.COLORED { background-color: #FFAD00
}
TR.COLORED { background-color: #FFAD00
}
TH.TITLE   { background-color: #EF8429;
             font-size: 28px;
             font-family: Arial, Helvetica, sans-serif;
}
-->
</STYLE>

---------------------------------------------------------------

//SimpleExample.jsp
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<!-- 
Illustration of very simple JSP custom tag. 
   
Taken from Core Servlets and JavaServer Pages
from Prentice Hall and Sun Microsystems Press, <A HREF="http://www.coreservlets.com/." TARGET=_blank>http://www.coreservlets.com/.</A> 
� 2000 Marty Hall; may be freely used or adapted.
-->
<HTML>
<HEAD>
<%@ taglib uri="csajsp-taglib.tld" prefix="csajsp" %>
<TITLE><csajsp:example /></TITLE>
<LINK REL=STYLESHEET
      HREF="JSP-Styles.css"
      TYPE="text/css">
</HEAD>
<BODY>
<H1><csajsp:example /></H1>
<csajsp:example />
</BODY>
</HTML>
---------------------------------------------------------------

//csajsp-taglib.tld

<?xml version="1.0" encoding="ISO-8859-1" ?>
<!DOCTYPE taglib
 PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.1//EN"
 "http://java.sun.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd">
<!-- a tag library descriptor -->
<taglib>
  <!-- after this the default space is
        "http://java.sun.com/j2ee/dtds/jsptaglibrary_1_2.dtd"
   -->
  <tlibversion>1.0</tlibversion>
  <jspversion>1.1</jspversion>
  <shortname>csajsp</shortname>
  <!-- ** CHANGED FROM "urn" TO "uri" IN TOMCAT 3.1 ** -->
  <uri></uri>
  <info>
    A tag library from Core Servlets and JavaServer Pages,
    <A HREF="http://www.coreservlets.com/." TARGET=_blank>http://www.coreservlets.com/.</A> 
  </info>
<!--
  <tag>
    The name (after prefix) tag will have in JSP code
    <name>example</name>
    The actual class implementing tag. In
    Tomcat 3.1 beta, it MUST be in a package.
    <tagclass>coreservlets.tags.ExampleTag</tagclass>
    Descriptive information about tag.
    <info>Simplest example: inserts one line of output</info>
    One of three values describing what goes between
    start and end tag. 
      empty: no body 
      JSP: body that is evaluated by container normally,
           then possibly processed by tag
      tagdependent: body is only processed by tag;
                    JSP in body is not evaluated. 
    ** NOTE: TOMCAT 3.1 FINAL DOES NOT SUPPORT BODYCONTENT **
    ** THE BETA SUPPORTED IT, AND IT IS PART OF SPEC, BUT... **
    <bodycontent>empty</bodycontent>
  </tag>      
-->
  <tag>
    <name>example</name>
    <tagclass>coreservlets.tags.ExampleTag</tagclass>
    <info>Simplest example: inserts one line of output</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>empty</bodycontent> -->
  </tag>      
  <tag>
    <name>simplePrime</name>
    <tagclass>coreservlets.tags.SimplePrimeTag</tagclass>
    <info>Outputs a random 50-digit prime.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>empty</bodycontent> -->
  </tag>
  <tag>
    <name>prime</name>
    <tagclass>coreservlets.tags.PrimeTag</tagclass>
    <info>Outputs a random N-digit prime.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT
    <bodycontent>empty</bodycontent> -->
    <attribute>
      <name>length</name>
      <required>false</required>
    </attribute>
  </tag>
  <tag>
    <name>heading</name>
    <tagclass>coreservlets.tags.HeadingTag</tagclass>
    <info>Outputs a 1-cell table used as a heading.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>JSP</bodycontent> -->
    <attribute>
      <name>bgColor</name>
      <required>true</required>  <!-- bgColor is required -->
    </attribute>
    <attribute>
      <name>color</name>
      <required>false</required>
    </attribute>
    <attribute>
      <name>align</name>
      <required>false</required>
    </attribute>
    <attribute>
      <name>fontSize</name>
      <required>false</required>
    </attribute>
    <attribute>
      <name>fontList</name>
      <required>false</required>
    </attribute>
    <attribute>
      <name>border</name>
      <required>false</required>
    </attribute>
    <attribute>
      <name>width</name>
      <required>false</required>
    </attribute>
  </tag>
  <tag>
    <name>debug</name>
    <tagclass>coreservlets.tags.DebugTag</tagclass>
    <info>Includes body only if debug param is set.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>JSP</bodycontent> -->
  </tag>
  <tag>
    <name>filter</name>
    <tagclass>coreservlets.tags.FilterTag</tagclass>
    <info>Replaces HTML-specific characters in body.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>JSP</bodycontent> -->
  </tag>
  <tag>
    <name>repeat</name>
    <tagclass>coreservlets.tags.RepeatTag</tagclass>
    <info>Repeats body the specified number of times.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>JSP</bodycontent> -->
    <attribute>
      <name>reps</name>
      <required>true</required>
      <!-- rtexprvalue indicates whether attribute
           can be a JSP expression. -->
      <rtexprvalue>true</rtexprvalue>
    </attribute>
  </tag>
  <tag>
    <name>if</name>
    <tagclass>coreservlets.tags.IfTag</tagclass>
    <info>if/condition/then/else tag.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>JSP</bodycontent> -->
  </tag>
  <tag>
    <name>condition</name>
    <tagclass>coreservlets.tags.IfConditionTag</tagclass>
    <info>condition part of if/condition/then/else tag.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>JSP</bodycontent> -->
  </tag>
  <tag>
    <name>then</name>
    <tagclass>coreservlets.tags.IfThenTag</tagclass>
    <info>then part of if/condition/then/else tag.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>JSP</bodycontent> -->
  </tag>
  <tag>
    <name>else</name>
    <tagclass>coreservlets.tags.IfElseTag</tagclass>
    <info>else part of if/condition/then/else tag.</info>
    <!-- TOMCAT 3.1 DOES NOT SUPPORT BODYCONTENT 
    <bodycontent>JSP</bodycontent> -->
  </tag>
</taglib>
---------------------------------------------------------------

[This message has been edited by maha anna (edited April 26, 2001).]

[JiaPei Jen]

I am lucky for having the attention of both Mr. Hanna and Ms. Maha Anna. Ms. Maha Anna, I have tried your method. I placed the JSP, its style sheet, and library descriptor files under the sub-directory of my web application root directory. The error message is the same: cannot parse the library descriptor. By the way, where do you place the compile file ExampleTag.class, of ExampleTag.java? I placed it under the directory in accordance with the WebLogic 6.0 guide.

[maha anna]

Jen,
I am sorry, forgot to mention about ExampleTag.class 's location in previous post. In tomcat I kept it under ....WEB-INF/classes dir.
Since ExampleTag.java has package coreservlets.tags; statement as first line, I created coreservlets\tags dir under ".../WEB-INF/classes" dir and stored like this.
C:\jakarta-tomcat\webapps\MISApp\WEB-INF\classes\coreservlets\tags\ExampleTag.class
Where did you keep this tag handler .class file? It has to be under classpath known to the servlet engine. Did you remove all trace of your modification for this tag in web.xml?
Any web logic users can come forward to help ?
regds
maha anna

package coreservlets.tags;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.io.*;
/** Very simple JSP tag that just inserts a string
 *  ("Custom tag example...") into the output.
 *  The actual name of the tag is not defined here;
 *  that is given by the Tag Library Descriptor (TLD)
 *  file that is referenced by the taglib directive
 *  in the JSP file.
 *  <P>
 *  Taken from Core Servlets and JavaServer Pages
 *  from Prentice Hall and Sun Microsystems Press,
 *  <A HREF="http://www.coreservlets.com/." TARGET=_blank>http://www.coreservlets.com/.</A> 
 *  © 2000 Marty Hall; may be freely used or adapted.
 */
public class ExampleTag extends TagSupport {
  public int doStartTag() {
    try {
      JspWriter out = pageContext.getOut();
      out.print("Custom tag example " +
                "(coreservlets.tags.ExampleTag)");
    } catch(IOException ioe) {
      System.out.println("Error in ExampleTag: " + ioe);
    }
    return(SKIP_BODY);
  }
}

regds
maha anna
[This message has been edited by maha anna (edited April 26, 2001).]