Help! pageContext is NULL in custom tag constructor!

I'm having a problem with a custom tag class, and I'm not sure whether it's because I'm doing something wrong, or because I'm running into a bug with Tomcat, JDK1.4b2, or something else. Basically, I'm finding that the pageContext object is null in the constructor of a custom tag class... something that I'm pretty sure is NOT supposed to happen.
I'm running JDK1.4b2 with Forte CE 3.1 (the bug predates the jumbo fix that brought it up to 3.0) and using Forte's embedded Tomcat.
I'm not sure whether it matters, but here's the sequence of events:
A servlet gets launched,
instantiates an object of type Error_list,
binds Error_list to the request object, and
forwards to a JSP that uses the custom tag defined by ListErrorsTag.
Unfortunately, pageContext is null in ErrorListTag's constructor, so the attempt to get the request object from the pageContext object generates a NullPointerException.
The SERVLET: *****************************************
// relevant lines from the servlet instantiating the object, binding it, and forwarding...
     Error_list errors = new Error_list("BAD_THINGS", "crash and burn");
     request.setAttribute("errors",errors);
     ServletContext sc = this.getServletContext();
     RequestDispatcher rd = sc.getRequestDispatcher("admin_category_create.jsp");
     rd.forward(request,response);
The JSP: ************************************************
In the JSP "admin_category_create.jsp" itself, I specify the taglib:
     <%@ taglib uri='/WEB-INF/AdminTags.tld' prefix = 'admin' %>
and reference it:
     <admin:listErrors>The errors will be listed here</admin:listErrors>
The Explosion of the Taglib: ************************
// beginning of Taglib class:
public class ListErrorsTag extends BodyTagSupport {
    private Error_list errors;
    public ListErrorsTag() {
    super()
    try {
         if (pageContext == null)
             System.out.println("uh oh! pageContext is null");
         ServletRequest request = pageContext.getRequest();
         errors = (Error_list)request.getAttribute("errors");
    catch (NullPointerException e) {
         System.out.println("boom!");
The Result: **************************************
Tomcat's error log:
uh oh! pageContext is null
boom!
if I eliminate the try/catch and allow the NullPointerException to take place, I get:
Error: 500
Location: /admin_category_create.jsp
Internal Servlet Error:
javax.servlet.ServletException
     at org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:459)
     at _0002fadmin_0005fcategory_0005fcreate_0002ejspadmin_0005fcategory_0005fcreate_jsp_0._jspService(_0002fadmin_0005fcategory_0005fcreate_0002ejspadmin_0005fcategory_0005fcreate_jsp_0.java:338)
     at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:119)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:177)
     at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:318)
     at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:391)
     at org.netbeans.modules.web.tomcat.JspServlet.service(JspServlet.java:91)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at org.apache.tomcat.core.ServletWrapper.doService(ServletWrapper.java:404)
     at org.apache.tomcat.core.Handler.service(Handler.java:286)
     at org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
     at org.apache.tomcat.facade.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:194)
     at admin.processRequest(admin.java:126)
     at admin.doPost(admin.java:144)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at org.apache.tomcat.core.ServletWrapper.doService(ServletWrapper.java:404)
     at org.apache.tomcat.core.Handler.service(Handler.java:286)
     at org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
     at org.apache.tomcat.core.ContextManager.internalService(ContextManager.java:797)
     at org.apache.tomcat.core.ContextManager.service(ContextManager.java:743)
     at org.apache.tomcat.service.http.HttpConnectionHandler.processConnection(HttpConnectionHandler.java:210)
     at org.apache.tomcat.service.TcpWorkerThread.runIt(PoolTcpEndpoint.java:416)
     at org.apache.tomcat.util.ThreadPool$ControlRunnable.run(ThreadPool.java:498)
     at java.lang.Thread.run(Thread.java:539)
Root cause:
java.lang.NullPointerException
     at AdminTags.ListErrorsTag.(ListErrorsTag.java:32)
     at _0002fadmin_0005fcategory_0005fcreate_0002ejspadmin_0005fcategory_0005fcreate_jsp_0._jspService(_0002fadmin_0005fcategory_0005fcreate_0002ejspadmin_0005fcategory_0005fcreate_jsp_0.java:272)
     at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:119)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:177)
     at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:318)
     at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:391)
     at org.netbeans.modules.web.tomcat.JspServlet.service(JspServlet.java:91)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at org.apache.tomcat.core.ServletWrapper.doService(ServletWrapper.java:404)
     at org.apache.tomcat.core.Handler.service(Handler.java:286)
     at org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
     at org.apache.tomcat.facade.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:194)
     at admin.processRequest(admin.java:126)
     at admin.doPost(admin.java:144)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at org.apache.tomcat.core.ServletWrapper.doService(ServletWrapper.java:404)
     at org.apache.tomcat.core.Handler.service(Handler.java:286)
     at org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
     at org.apache.tomcat.core.ContextManager.internalService(ContextManager.java:797)
     at org.apache.tomcat.core.ContextManager.service(ContextManager.java:743)
     at org.apache.tomcat.service.http.HttpConnectionHandler.processConnection(HttpConnectionHandler.java:210)
     at org.apache.tomcat.service.TcpWorkerThread.runIt(PoolTcpEndpoint.java:416)
     at org.apache.tomcat.util.ThreadPool$ControlRunnable.run(ThreadPool.java:498)
     at java.lang.Thread.run(Thread.java:539)

Doing a little more experimentation, I discovered that pageContext is null in the constructor, but not null in the otherDoStartTagOperations() method (called by the doStartTag() method of the tag's class... it's something Forte forces you to do).
Is this normal? I was under the impression that pageContext is supposed to be defined EVERYWHERE in any class that extends BodyTagSupport... including the class' own constructor.
On a related topic, is there documentation somewhere as to what, exactly, Forte is doing behind the scenes when it's managing a taglib (how it keeps track of them, where it puts config files, how the entries it makes in them are different or extended from the normal layout, etc.)? At the moment, I suspect that half of the grief I'm having with writing taglibs is caused by Forte itself forcing me to do things in a roundabout way that bears little resemblance to the ways shown in different books on the topic (and in fact all but ensures that nearly every published example will fail and require major rewriting because of the way it forces tag classes to be structured), but I don't see any easy way to let Forte handle compiling the classes and testing them with its embedded Tomcat, but do the config file housekeeping myself I can be in control of it.

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<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html" %>
make a C:\WEB-INF\ directory on your PC and copy in there your tlds
(C:\WEB-INF\struts-html.tld). The same for linux: /WEB-INF/struts-html.tld.
So you do not have to change anything in web.xml nor in the jsp pages!
Bye,
Marco.
"marco" <[email protected]> ha scritto nel messaggio
news:cfhrgj$bcj$[email protected]..
> Davis,
> thanks for the reply. I followed your suggestion and now I am able to see
> the code assist working.
> I am currently using the lomboz editor, but one thing that is missing in
> lomboz and is present in the structured editor (and in Intellij Idea) is
the
> ability to see where a tag is opened and closed, also for html tags.
Perhaps
> to someone this should seem not so important, but for me it is very
usefull!
>
> As a first impression, I can only make a lot compliments to both
> contributions (ObjectWeb and IBM).
>
> Bye,
> Marco.
>
>
> "David Williams" <[email protected]> ha scritto nel messaggio
> news:[email protected]..
> >
> > No, you're not missing anything. Its just with that version of code the
> > "tld resolver" (that knows where to look for TLD's) is not correct. I
> > haven't tried it with struts, but with a minor test I tried,
> > I just made a copy of the TLD to put in the same folder as the JSP file.
> > Then the editor (and content asssit), can find it and all should be ok.
Of
> > course, I'm not suggesting this for a long term solution, but just to
see
> > if it allows you to get a little further in evaluating overall.
>
>

How to add a reference to help for a custom tag

Hello,
I would like to add an icon (question mark icon) to my custom tag (in tag libraries view). Then, when I press this icon I would like to see some .html page with description of a tag as it is done for a struts tags.
Is it possible?
If yes please tell me how to do it.
Thanks,
Damian

There are a variety of customization options available for BEA Workshop. Through metadata you can define renderings for custom tags, tag appearance in the tag libraries view, customize the tag editors, and much more.
Information about customization can be found at the following link: http://workshopstudio.bea.com/docs/tlei.htm
Adding custom tag documention to the Tag Libraries view is not currently a configuration option but would be a useful addition. I will file an enchancement request for this functionality.

Why doesn't my custom tag work?

First, my backend database is MS Access. Nothing I can do about that, unfortunately.
I have defined three custom tags (no body, no attributes) to display report information from my project tracking/metrics Access database:
<prefix:showProjectInfo />
<prefix:showProjectTeam />
<prefix:showProjectHistory />
In my JSP, the first tag I use, <prefix:showProjectInfo />, works perfectly. However, <prefix:showProjectTeam /> gives no output.
First, here is the tld file that defines the tags (report.tld):
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE taglib
        PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN"
        "http://java.sun.com/dtd/web-jsptaglibrary_1_2.dtd">
<taglib>
    <tlib-version>1.0</tlib-version>
    <jsp-version>1.2</jsp-version>
    <short-name>report</short-name>
    <uri>/report</uri>
    
    
   
   <tag>
        <name>showProjectInfo</name>
        <tag-class>mil.usaf.rad.metrics.report.showProjectInfoTag</tag-class>
        <body-content>empty</body-content>
        <description>Shows the basic project information</description>
   </tag>
   <tag>
        <name>showProjectTeam</name>
        <tag-class>mil.usaf.rad.metrics.report.showProjectTeamTag</tag-class>
        <body-content>empty</body-content>
   </tag>
   <tag>
        <name>showProjectHistory</name>
        <tag-class>mil.usaf.rad.metrics.report.showProjectHistoryTag</tag-class>
        <body-content>empty</body-content>
   </tag>
</taglib>Next, here is the relevant section of web.xml that defines this taglib:
<taglib>
        <taglib-uri>/WEB-INF/report.tld</taglib-uri>
        <taglib-location>/WEB-INF/report.tld</taglib-location>
</taglib>Next, the code for showProjectTeamTag.java:
* showProjectTeam.java
* Created on March 9, 2005, 10:46 AM
package mil.usaf.rad.metrics.report;
import java.io.*;
import java.sql.*;
import java.lang.Integer;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
* @author jason.ferguson
public class showProjectTeamTag extends TagSupport
    public showProjectTeamTag()
        super();
    public int doAfterBody() throws JspException
        HttpServletRequest req = (HttpServletRequest) pageContext.getRequest();
        int pr_id = Integer.parseInt(req.getParameter("pr_id"));
        JspWriter out = pageContext.getOut();
        Connection conn = null;
        Statement stmt = null;
        ResultSet rs = null;
        try
           out.print("test");
           Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
           conn = DriverManager.getConnection("jdbc:odbc:Metrics");
        catch (Exception e)
            throw new JspException(e.getMessage());
        String queryGetTeam = "SELECT Projects.pr_id, Accounts.name AS Name, Sum(Schedule.hours) AS SumOfhours FROM tblTAAccounts AS Accounts INNER JOIN ((tblTAScheduleEntries AS Schedule INNER JOIN tblProjectRelease AS ProjectRelease ON Schedule.projectID = ProjectRelease.tblFKTimeAccntProject) INNER JOIN tblPMProjects AS Projects ON ProjectRelease.Release_ID = Projects.pr_id) ON Accounts.accountID = Schedule.accountID WHERE Projects.pr_id=" + pr_id + " GROUP BY Projects.pr_id, Accounts.name, ProjectRelease.Release_number, Projects.Project_name";
        try
            out.print(queryGetTeam);
            stmt = conn.createStatement();
            rs = stmt.executeQuery(queryGetTeam);
            if (rs == null)
                out.print("No Results!");
            out.print("<table>\n");
            out.print("<tr>\n");
            out.print("<th>Name</th>\n");
            out.print("<th>Total Hours</th>\n");
            out.print("</tr>\n");
            while(rs.next())
                out.print("<tr>\n");
                out.print("<td>" + rs.getString("Name") + "</td>\n");
                out.print("<td>" + rs.getInt("SumOfhours") + "</td>\n");
                out.print("</tr>\n");
            out.print("</table>\n");
            rs.close();
            stmt.close();
            conn.close();
        catch (Exception e)
            throw new JspException(e.getMessage());
        return SKIP_BODY;
}Finally, projectdetail.jsp, where the tag is called:
<%@page contentType="text/html"%>
<%@page pageEncoding="UTF-8"%>
<%@page import="java.sql.*" %>
<%@page import="java.lang.Integer" %>
<%@taglib uri="/WEB-INF/report.tld" prefix="report" %>
<html>
<head><title>Project Detail</title></head>
<body>
<h1 align="center">Project Status</h1>
<h3>Project Description</h3>
<report:showProjectInfo />
<h3>Team Members</h3>
<report:showProjectTeam />
</body>
</html>The first tag, <report:showProjectInfo />, works fine. However, I get no output whatsoever when the system encounters <report:showProjectTeam />. I am a relative newbie at this, so any help is appreciated.
Jason

It doesnt seem to matter if the code is in doStartTag(), doEndTag(), orr any of the other functions.
I also put, as the first item in the function:
System.out.println("TEST");Nothing.
Just as an aside, here is the code for the <prefix:showProjectInfo />. Maybe I made a mistake in it? I closed the resultset and connection...
import java.io.*;
import java.sql.*;
import java.lang.Integer;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
* @author jason.ferguson
public class showProjectInfoTag extends BodyTagSupport
    public int doEndTag() throws JspException
        HttpServletRequest req = (HttpServletRequest) pageContext.getRequest();
        int pr_id = Integer.parseInt(req.getParameter("pr_id"));
        JspWriter out = pageContext.getOut();
        Connection conn = null;
        Statement stmt = null;
        ResultSet rs = null;
        try
           Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            conn = DriverManager.getConnection("jdbc:odbc:Metrics");
        catch (Exception e)
            throw new JspException(e.getMessage());
        String queryProjectInfo = "SELECT * FROM tblPMProjects WHERE pr_id=" + pr_id;
        try
            stmt = conn.createStatement();
            rs = stmt.executeQuery(queryProjectInfo);
            while (rs.next())
                out.print("<table border=\"1\" style=\"border-collapse:collapse\">\n");
                out.print("<tr>\n");
                out.print("<td><b>Project Name:</b>" + rs.getString("Project_name") + "</td>\n");
                out.print("<td align=\"right\"><b>RAD Number:</b>" + rs.getString("tblProjectNumber") + "</td>\n");
                out.print("</tr>\n");
                out.print("<tr>\n");
                out.print("<td>Project description: " + rs.getString("Project_description") + "</td>\n");
                out.print("</tr>\n");
                out.print("<tr>\n");
                out.print("<td>Customer: " + rs.getString("Customer_POC") + "</td>");
                out.print("<tr>\n");
                out.print("<tr>\n");
                out.print("<td>Customer Unit: " + rs.getString("Customer_OFC") + "</td>\n");
                out.print("</tr>\n");
                out.print("<tr>\n");
                out.print("<td>Customer Phone: " + rs.getString("Customer_phone") + "</td>\n");
                out.print("</tr>\n");
                out.print("</table>\n");
                rs.close();
                stmt.close();
                conn.close();
        catch (Exception e)
            throw new JspException(e.getMessage());
        finally
            //conn.close();
        return SKIP_BODY;

Help! pageContext is NULL in custom tag constructor!

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