Commenting out custom tag

I have a simple custom tag. but when i use "" for commenting out, it still implements the custom tag line.
how should i do to comment out the custom tag?
thanks...

is an HTML comment
<%-- --%> is a JSP comment

Similar Messages

Custom Tag Implementation seems inefficient

I've been playing around a bit (alright, so maybe not all that much)
          with custom tags, and it seems like the actual implementation of custom
          tags (tag handler object(s) per tag) is much more resource-intensive
          than would be justified. With Weblogic 5.1 SP6, has anyone had the
          opportunity to compare performance of a typical JSP page w/ and w/out
          custom tags?
          My first impression of custom tags was that you could define tags
          and behaviors that the JSP compiler would then compile into your JSP
          class; there would be no performance hit during page execution. The Java
          code used to write these tags would either be included inline in the JSP
          page code, or else act essentially as static (threadsafe) classes into
          which threads executing JSP pages would call into. This approach means
          less resources consumed and less setup/teardown time in exchange for
          fatter JSPC'd code.
          Instead (and correct me if I am wrong), it appears that each
          distinct custom tag has a pool of instantiated handler objects lying
          around in memory, and each time a custom tag is used, there is a
          little performance hit in the setup & teardown of each handler object's
          pageContext, etc...
          Now admittedly, as another poster (I believe Mr. Purdy) pointed out,
          a "little" ain't all that much... unless there are thousands of those
          "little" hits.
          Moreover, I don't see much benefit in having instantiated objects do
          the heavy lifting. I'd rather have my auto-compiled JSP classes be a
          little more bloated than suffer any performance hit. (I do, however,
          like the fact that custom tags allows for cleaner JSP code, not to
          mention makes for a cleaner break between the creative and coding work.)
          For those of you who've had more extensive experience with custom
          tags, am I missing the target? Is the performance hit negligible for
          heavily-used or complex pages? And/or is the performance hit outweighed
          by code and development cleanliness?
          Thanks for any input.
          Jack


Hi Sri
          Looks like you've found an inefficiency in WebLogic's JSP compiler - it
          should be reusing tag instances within the same page. BEA should fix this
          hopefully.
          > So even if a page has 4 tags and 100 users, we have 400 objects just
          > because we use tags.
          Sure, assuming you have 100 concurrent users (and 100 threads in the servlet
          engine). Though creating 400 objects is not a big deal in Java; most non
          trivial Java applications / services create millions of objects.
          Its also worth noting that having a seperate object instance per tag per
          calling thread means that you don't have to do any synchronisation in the
          custom tag (since you're guarenteed to be called by one thread only) so you
          get maximum thread throughput at the expense of some object allocation.
          If you really don't like the idea of creating a few java objects per request
          you could use XSLT to post process JSP files to replace tag occurencies with
          Java scriptlets - though I'm not sure the extra complexity and restrictions
          that this mechanism imposes is worth it at all. Custom tags rock! ;-)
          J.
          James Strachan
          =============
          email: [email protected]
          web: http://www.metastuff.com
          "Sri" <[email protected]> wrote in message
          news:[email protected]...
          > This post had some interesting aspects about custom tags that contradict
          > what I see in the generated java code by the JSP container. I am using
          > weblogic 5.1 sp6 and I have a jsp file that uses a custom tag "xyz:for" a
          > couple of times. the tags are not nested.
          > The java code indicates that two separate instances for the "xyz:for" tag
          > were created.
          >
          > try
          >
          > calicothunder_presentation_tags_ForTag_0 = new
          > calico.thunder.presentation.tags.ForTag();
          >
          > ..............
          >
          > } finally
          >
          > if (_calico_thunder_presentation_tags_ForTag_0 != null)
          > calicothunder_presentation_tags_ForTag_0.release();
          > }
          >
          > Further down
          >
          > try {
          > calicothunder_presentation_tags_ForTag_1 = new
          > calico.thunder.presentation.tags.ForTag();
          > ...............
          >
          > } finally
          >
          > if (_calico_thunder_presentation_tags_ForTag_1 != null)
          > calicothunder_presentation_tags_ForTag_1.release();
          > }
          >
          > The code is creating two different objects for every request. It is not
          > reusing the same object.
          > The release is just cleaning up the current instance, which may be garbage
          > collected at some later stage.
          > So even if a page has 4 tags and 100 users, we have 400 objects just
          > because we use tags.
          >
          > Just trying to understand this better..
          > thanks - Sri
          >
          >
          >
          > "James Strachan" <[email protected]> wrote in message
          > news:[email protected]...
          > > Hi Jack
          > >
          > > I think you're right to be concerned and it is a valid concern.
          > >
          > > In the scheme of things in my experience the cost of using custom tags
          is
          > > quite minimal. Tag instances are reused on the same page so if I have
          > > several non-nested <foo:bar> tags on a page the single FooBarTag
          instance
          > > will be reused for each tag occurance.
          > >
          > > Consider other Java code, say, string concatenation. Consider the
          > following
          > > expression.
          > >
          > > String c = a + b;
          > >
          > > Fairly minimal code you might think. However this line actually involves
          > the
          > > creation of a StringBuffer instance, the call of 2 methods and the
          > creation
          > > of a second String object instance (never mind the internal char[]
          object
          > > instance that is created inside the new Strings constructor).
          > >
          > > A typical use of a custom tag involves one object construction, N
          > > setProperty() method calls (one for each attribute of the tag) and the
          > > startTag / endTag method calls.
          > >
          > > So on balance I'd say the custom tags mechanism is quite small and
          > > efficient.
          > >
          > > Though note that if you use large numbers (say hundreds) of different
          > kinds
          > > of tags then you'll have a much greater object allocation overhead.
          > >
          > > --
          > > J.
          > >
          > > James Strachan
          > > =============
          > > email: [email protected]
          > > web: http://www.metastuff.com
          > > "Jack Lin" <[email protected]> wrote in message
          > > news:[email protected]...
          > > > I've been playing around a bit (alright, so maybe not all that much)
          > > > with custom tags, and it seems like the actual implementation of
          custom
          > > > tags (tag handler object(s) per tag) is much more resource-intensive
          > > > than would be justified. With Weblogic 5.1 SP6, has anyone had the
          > > > opportunity to compare performance of a typical JSP page w/ and w/out
          > > > custom tags?
          > > >
          > > > My first impression of custom tags was that you could define tags
          > > > and behaviors that the JSP compiler would then compile into your JSP
          > > > class; there would be no performance hit during page execution. The
          Java
          > > > code used to write these tags would either be included inline in the
          JSP
          > > > page code, or else act essentially as static (threadsafe) classes into
          > > > which threads executing JSP pages would call into. This approach means
          > > > less resources consumed and less setup/teardown time in exchange for
          > > > fatter JSPC'd code.
          > > > Instead (and correct me if I am wrong), it appears that each
          > > > distinct custom tag has a pool of instantiated handler objects lying
          > > > around in memory, and each time a custom tag is used, there is a
          > > > little performance hit in the setup & teardown of each handler
          object's
          > > > pageContext, etc...
          > > > Now admittedly, as another poster (I believe Mr. Purdy) pointed
          out,
          > > > a "little" ain't all that much... unless there are thousands of those
          > > > "little" hits.
          > > > Moreover, I don't see much benefit in having instantiated objects
          do
          > > > the heavy lifting. I'd rather have my auto-compiled JSP classes be a
          > > > little more bloated than suffer any performance hit. (I do, however,
          > > > like the fact that custom tags allows for cleaner JSP code, not to
          > > > mention makes for a cleaner break between the creative and coding
          work.)
          > > >
          > > > For those of you who've had more extensive experience with custom
          > > > tags, am I missing the target? Is the performance hit negligible for
          > > > heavily-used or complex pages? And/or is the performance hit
          outweighed
          > > > by code and development cleanliness?
          > > >
          > > > Thanks for any input.
          > > > Jack
          > > >
          > > >
          > >
          > >
          >
          >

Add customized tags on shared review comments

Hi,
We have been using shared review to do our document review heavily. Recently I got a request from our stakeholder to add customized tags so we can assign comments in different categories.
Is it doable with some customization effort? I did some research online and found out Acrobat XI supports customization Wizard and for earlier version (we are on Pro 9), you can do customization using JavaScript, but it's not clear to me if these customization efforts can be applied on shared review PDF, or it's just on regular PDF.
Does anyone have experience on Acrobat customization? Any thought or information will be appreciated.
Thanks,
-Yunju

Hi Ajlan,
Thanks for the answer. I also found out about the customization wizard later. Now I'm researching how to use the wizard and deploy the customization feature we desire.
Here are the things we want to do:
- Creating customized menu so we can assign comments to different categories, something like set the comment status
- Modify the workflow. Instead of asking reviewer to "connect" or "cancel" when they first open the PDF, we can to only show "connect"
I also have couple of questions about the wizard:
1. Are the features I describe above can be done through wizard?
2. If we deploy the changes using Acrobat 9 + wizard, will users with all version Acrobat/Reader see the same end result and preform regular shared review operations without problem?
Thanks for the answer.
-Yunju

.exception.JspParseExcept Cannot parse custom tag with short name [out].

Hi
     I have almost migrated an application from jboss to CE 7.1 sp3 maxdb 32 bit
     however I am getting the following error on c:out tag of standard jslt.
Runtime error in processing of the JSP file [C:\usr\sap\CE1\J00\j2ee\cluster\apps\<....>\servlet_jsp\<application_context_name>\root\jsp\view\<jsp_name>.jsp].
Line:----
The error is: com.sap.engine.services.servlets_jsp.jspparser_api.exception.JspParseException: Cannot parse custom tag with short name [out].02004C4F4F50001F0000002D000012B000B0688132009833
Line:----
Do anybody have some idea why is it happening.
My guess would be because of jslt version mismatch. but its working fine in jboss. I am not sure what version cE 7.1 support may be 1.2. any idea how to chek the supported version in the server.
The jsp code is something like
Line:----
<code>
<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core" %>
<%@ taglib prefix="c_rt" uri="http://java.sun.com/jstl/core_rt" %>
<c:url var="thumbnailStream" value="/do/<action_tag>">
           <c_rt:param name="stream_id"      value="<%= <variable1> %>"/>
           <c:param    name="stream_id_type" value="<variable2>"/>
           <c:param    name="content_kind"   value="<variable3>"/>
        </c:url>
<img border="0" src="<c:out value="$"/>">
</code>
Line:----
from the SAP help text its said that jslt is being overrided by server to use from global library rather than local webapplication library. Couls woud explain where is this global library located in the server directory.
Thx.
Ashutosh

Hi are you able to solve this issue.I am getting similar kind of issue.
Logs for the same are ::
Caused by: com.sap.engine.services.servlets_jsp.jspparser_api.exception.JspParseException: Cannot parse custom tag with short name out.
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.xmlsyntax.CustomJspTag.action(CustomJspTag.java:183)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.ElementCollection.action(ElementCollection.java:59)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.JspIncludeDirective.action(JspIncludeDirective.java:51)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.ElementCollection.action(ElementCollection.java:59)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.JspElement.customTagAction(JspElement.java:994)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.JspElement.action(JspElement.java:228)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.ElementCollection.action(ElementCollection.java:59)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.ElementCollection.action(ElementCollection.java:69)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.GenerateJavaFile.generateJavaFile(GenerateJavaFile.java:72)
at com.sap.engine.services.servlets_jsp.server.jsp.JSPProcessor.parse(JSPProcessor.java:270)
at com.sap.engine.services.servlets_jsp.server.jsp.JSPProcessor.generateJavaFile(JSPProcessor.java:194)
at com.sap.engine.services.servlets_jsp.server.jsp.JSPProcessor.parse(JSPProcessor.java:126)
at com.sap.engine.services.servlets_jsp.jspparser_api.JSPChecker.getClassName(JSPChecker.java:319)
at com.sap.engine.services.servlets_jsp.jspparser_api.JSPChecker.compileAndGetClassName(JSPChecker.java:248)
at com.sap.engine.services.servlets_jsp.jspparser_api.JSPChecker.getClassNameForProduction(JSPChecker.java:178)
at com.sap.engine.services.servlets_jsp.jspparser_api.JSPChecker.processJSPRequest(JSPChecker.java:109)
at com.sap.engine.services.servlets_jsp.jspparser_api.JspParser.generateJspClass(JspParser.java:154)
at com.sap.engine.services.servlets_jsp.server.servlet.JSPServlet.service(JSPServlet.java:193)
... 47 more
Caused by: com.sap.engine.services.servlets_jsp.jspparser_api.exception.JspParseException: Attribute value of <c:out> can accept only static values.
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.taglib.TagBeginGenerator.calculateAttributeValue(TagBeginGenerator.java:476)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.taglib.TagBeginGenerator.generateSetters(TagBeginGenerator.java:394)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.taglib.TagBeginGenerator.generateServiceMethodStatements(TagBeginGenerator.java:562)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.taglib.TagBeginGenerator.generate(TagBeginGenerator.java:678)
at com.sap.engine.services.servlets_jsp.jspparser_api.jspparser.syntax.xmlsyntax.CustomJspTag.action(CustomJspTag.java:181)
... 64 more

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;

Custom Tag issue and then ApplicationID?

Hello,
is there anybody out there who can help me with the following
problem:
I installed ColdFusion 4.5 Server on my Windows XP machine
and wanted to access an already built CF application. When
accessing
the main default page, i got the following error:
"Cannot find CFML template for custom tag
CFA_APPLICATIONINITIALIZE.
ColdFusion attempted looking in the tree of installed custom
tags but
did not find a custom tag with this name. "
I copied the same Administrator settings, code and folders
from the
working production server to my local machine and it just
doesn't seem
to work. (I couldn't find any differences to the working
application)
I tried to fix it by copying the custom tag folder (located
under allaire/spectra/customtags/) to C:\CFusion\CustomTags which
somehow cleared the previous error but gave me the following new
one:
"Error Occurred While Processing Request > Error
Diagnostic Information > This application can't be located by
name. Use ApplicationID instead"
Please, i appreciate any kind of comment on this post (i have
been trying to fix this for the past 3 days!)
Thanks,
bbinto

Spectra requires 4.5.1 or 5.
Run the Spectra install to set up all the correct mappings
and the webtop. Then copy over the custom application. It's been
awhile since I've dug into the folder structure of the webtop, so I
don't have a complete list of steps required for a Spectra app
deployment. So you still have some work ahead of you.
Just make sure you backup your database before the install,
mirror it, or use a new schema for the installation and then switch
over your datasources.
I would recommend an old Spectra book you can probably find
on eBay.
http://www.forta.com/books/0789723654/

How do you programmatically register custom tags through the adminapi?

Hello,
I am not able to find much documentation out on the net on how to write codes to programmatically register custom tags through the adminapi (extensions.cfc). The only examples I have been seeing involve setting up datasources. Any advice you can provide is appreciated. Thanks.
Best regards,
C. Lee

Short answer:
The problem is that the login method is a bit goofy in that it requires the password first and the username second. Assuming you are using a valid password (and not the string "password" you are showing), reversing them should solve your problem.
Long answer:
As background for those interested, in order to call any method in any of the Admin API CFCs, one does have to log in programmatically, providing a valid CF Admin password, or password/username combination if you have enabled multiple user logins for the CF Admin. (Multiple user logins in the Admin is an optional feature since CF 8.)
If one does not setup multiple user names, then you only need to pass a password to the login method (just as on the login page of the CF Admin). Technically, the default username in that case is "admin", and you can specify it if you want to, but again it has to be password then username, on this login method. (The Admin API was added in CF 7, before the multiple usernames feature was added, so it looks like they just added it as a new argument.)
You can learn more about multiple user logins in the CF Admin (and an option to change or remove the default "admin" username) an Adobe DevCenter article linked to from http://www.carehart.org/articles/#2009_1.
Note finally that the username/password field values are case-sensitive, even on Windows, and the default username really is "admin" not "Admin".
This discussion of needing to login is documented on the page that Adam pointed to (see the "using" and "examples" sections of the page). There's even a comment from someone pointing out the need to put them in password/username order (because it's not mentioned in the docs). I also just added a comment there about the case sensitivity, either of which could bite someone. Let's hope they update the docs in the next release to clarify both these points.
/charlie

Using custom tags - not a "how to do my homework" question.

Hi, I havn't done a heap of JSP and I'm experimenting with custom tags. I understand this may be elementary to some. I also expect there is probably some ready-to-go libary out there that would do this for me, I just wanted to do it from scratch, mostly as a learning exercise.
So I've got a servlet which runs a query, and sends two arrays of objects to a JSP, one is an array of column headings, the other is an array of arrays representing the rows of data.
The intention of the JSP is simply to display the data in a table.
I guess one question I have is:
What is the best way to apply styles to my table? Obviously I don't want to have to recompile the tag code to add/change styles. Is the best way to do it is to have another property of the tag that accepts the name of a style class?
So when I place the tag in my JSP it will looks like <test:report-table headings="..." rows="..." style="blue"/> and in the tag code it will look something like out.write("<table class=\" + classname + \"");I appreciate any comments on how good/bad my code/theory is. Any recomended additions/omissions?
The tag in the JSP looks like this.
        <test:report-table
            headings="<%= (Object[])request.getAttribute(\"columns\")%>"
            rows="<%= (Object[])request.getAttribute(\"rows\")%>"
        />The tag class looks like this.
bar.foo.test;
import java.io.IOException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.TagSupport;
public class ReportTable extends TagSupport
    private Object[] headings;
    public Object[] getHeadings() { return headings; }
    public void setHeadings(Object[] o) { this.headings = o; }
    private Object[] rows;
    public Object[] getRows() { return rows; }
    public void setRows(Object[] o) { this.rows = o; }
    public int doStartTag()
        JspWriter out = pageContext.getOut();
        try
            out.write("<table>");
            out.write("<tr>");
            for (int i = 0; i < headings.length; i++ )
                out.write("<td>" + headings[i] + "</td>");
            out.write("</tr>");
            for (int i = 0; i < rows.length; i++)
                out.write("<tr>");
                Object[] row = (Object[])rows;
for (int j = 0; j < row.length; j++)
out.write("<td>" + row[j] + "</td>");
out.write("</tr>");
out.write("</table>");
catch (IOException e)
e.printStackTrace();
return 0;
The tag definition in my tld looks like this
    <tag>
        <name>report-table</name>
        <tagclass>bar.foo.ReportTable</tagclass>
        <bodycontent>empty</bodycontent>
        <info> Report Table </info>
        <attribute>
            <name>headings</name>
            <required>true</required>
            <rtexprvalue>true</rtexprvalue>
            <type>java.util.Object[]</type>
        </attribute>
        <attribute>
            <name>rows</name>
            <required>true</required>
            <rtexprvalue>true</rtexprvalue>
            <type>java.util.Object[]</type>
        </attribute>
    </tag>

TimSparq wrote:
Cool, thanks for the input/advice, evanfets.
Yeah, my plan was now that I have a basic understanding of the mechanics of what's going on in the tags, I'll go and look into what ready-made stuff there is out there (like you suggest, JSTL).
And thanks for the advice regarding styles, exceptions and the return value. All appreciated.
I'll be taking a look into the tag files too.
Thanks again.Just another option on the styles. One thing I have done in similar situations is to generate a lot of class names and automatically apply them to the correct spot. Example:
<table class="reportTable">
<thead class="reportTableHead">
    <tr class="rtHeadRow"><th class="rtOddColumn">...</th><th class="rtEvenColumn">...</th></tr>
<thead>
<tbody class="reportTableBody">
    <tr class="rtOddRow"><td class="rtOddColumn">...</td><td class="rtEvenColumn">...</td></tr>
    <tr class="rtEvenRow"><td class="rtOddColumn">...</td><td class="rtEvenColumn">...</td></tr>
</tbody>
</table>This gives the web developer a large selection of selectors to work on:
table.reportTable -> Edit the entire table
table.reportTable tr -> Configure all rows in the table
table.reportTable tr.rtOddRow -> Configure the odd rows in the table
table.reportTable tr.rtOddRow td.rtEvenColumn -> Configure just the even columns in an odd row
etc...
You just communicate the class names that can be used and then the web designer generates a CSS to fit his needs.

Rendering A JPEG image with a custom tag

Hi All,
I have dilema. I'm trying to rendering a jpeg in IE/FireFox with a custom tag that I developed. I'm able to access the bean and invoke the getter method to return the InputStream property. But what gets rendered is the byte code not the image. I've tried just about anything I could think off. If any body has an answer I would difinitely appreciate it.
Thanks,
Tony
Below is the jsp, tld, bean and tag.
********************************* image.jsp ****************************************
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<%@ taglib uri="/WEB-INF/custom-chtml.tld" prefix="chtml" %>
<html>
<head>
<title>HTML Page</title>
</head>
<body bgcolor="#FFFFFF">
<chtml:img name="photo" property="file"/>
</body>
</html>
********************************* custom-chtml.tld **********************************
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.1//EN" "http://java.sun.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd">
<taglib>
<tlibversion>1.0</tlibversion>
<jspversion>1.1</jspversion>
<shortname>chtml</shortname>
<tag>
<name>img</name>
<tagclass>com.struts.taglib.CustomImgTag</tagclass>
<bodycontent>empty</bodycontent>
<attribute>
<name>name</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>property</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
</tag>
</taglib>
**************************** MemberPhotoBean.java ******************************
import java.io.InputStream;
* @author tony
* TODO To change the template for this generated type comment go to
* Window - Preferences - Java - Code Style - Code Templates
public class MemberPhotoValue {
     private String memberId;
     private int fileSize;
     private InputStream file;
     public MemberPhotoValue() {
     public MemberPhotoValue(String memberId, InputStream file) {
          this.memberId = memberId;
          this.file = file;
     public MemberPhotoValue(String memberId,int fileSize,InputStream file) {
          this.memberId = memberId;
          this.fileSize = fileSize;
          this.file = file;
     public String getMemberId(){
          return memberId;
     public void setMemberId(String memberId) {
          this.memberId = memberId;
     public int getFileSize() {
          return fileSize;
     public void setFileSize(int fileSize) {
          this.fileSize = fileSize;
     public InputStream getFile(){
          return file;
     public void setFile(InputStream file) {
          this.file = file;
*************************** CustomTagHandler.java ********************************
import java.io.*;
import javax.imageio.ImageIO;
import javax.servlet.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;
import java.awt.image.*;
import java.awt.*;
import javax.swing.ImageIcon;
import com.sun.image.codec.jpeg.*;
* JSP Tag Handler class
* @jsp.tag name = "CustomImg"
* display-name = "Name for CustomImg"
* description = "Description for CustomImg"
* body-content = "empty"
public class CustomImgTag implements Tag {
     private PageContext pageContext;
     private Tag parent;
     private String property;
     private String name;
     private Class bean;
     public int doStartTag() throws JspException {
          return SKIP_BODY;
     public int doEndTag() throws JspException {
     try {
     ServletResponse response = pageContext.getResponse();
     // read in the image from the bean
     InputStream stream = (InputStream) invokeBeanMethod();
     BufferedImage image = ImageIO.read(stream);          Image inImage = new ImageIcon(image).getImage();
     Graphics2D g = image.createGraphics();
     g.drawImage(inImage,null,null);
     OutputStream out = response.getOutputStream();
// JPEG-encode the image
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
encoder.encode(image);
     out.close();
} catch (IOException io) {
          throw new JspException(io.getMessage());
     return EVAL_PAGE;
     public void release(){}
private InputStream invokeBeanMethod() throws JspException {
     try {
     Object bean = null;
     if (null != pageContext.getAttribute(name)) {
     bean = (Object) pageContext.getAttributename);
     else if (null != pageContext.getSession().getAttribute(name)) {
     bean = (Object) pageContext.getSession().getAttribute(name);
     else if (null != pageContext.getRequest().getAttribute(name)) {
     bean = (Object) pageContext.getRequest().getAttribute(name);
     else {
     throw new JspException("Bean : "+name+" is not found in any pe.");
     Class[] parameters = null;
     Object[] obj = null;
     Method method = bean.getClass().getMethod("getFile",parameters);
     return (InputStream) method.invoke(bean,obj);
     } catch (NoSuchMethodException ne) {
     throw new JspException("No getter method "+property+" for bean : "+bean);
     } catch (IllegalAccessException ie) {
     throw new JspException(ie.getMessage());
     } catch (InvocationTargetException ie) {
     throw new JspException(ie.toString());
     public void setPageContext(PageContext pageContext) {
          this.pageContext = pageContext;
     public void setParent(Tag parent) {
          this.parent = parent;
     public Tag getParent() {
          return parent;
     public void setProperty(String property) {
          this.property = property;
     public void setName(String name) {
          this.name = name;
**************************************************************************************

If you have access to an image editing tool such as photoshop, I would advice you import the image into Phototshop and save it in a different format e.g, GIF format and re-import it into Final Cut Express HD. This could solve your rendering problem if all you need is to use a Still image.
Ayemenre

Customized Tags for Songs

I am a bit of an organization freak. I have been using J. River Media Center to play songs, but now that I have an iPod, I am disgruntled because when I copy the songs to my iPod, the images do not come over, and half the songs don't play.
I am trying to use iTunes now, but I cannot seem to figure out how to show custom tags. For example, in Media Center, I invented new tags that did not exist to allow me to categorize my tracks in different ways. I made a Mood tag, a Principal Instrument tag, a How Discovered tag, a Country tag, a Status tag, a Fave tag, etc. iTunes does not seem to have a way to show these tags or allow me to create them. Am I missing something?
[email protected]

But why not? It is a no-brainer. Why not provide people with the convenience of creating their own tags? I think I shall stay with Media Center just for this reason.
I know I can put tags in the Grouping or Comments field, but this is really a visual inconvenience when you have many tags. For example, I have a song that I want to tag with Piano, Norway, Faves and Upbeat for the purpose of creating separate playlists. I know I can set the smart playlist to say, "Grouping contains Piano" or "Grouping contains Faves", but visually this is an inconvenience, and when you have tons of songs you want to categorize in many different ways, it is more convenient to be able to create separate tags entirely.

Weblogic Commerce Server 3.5 runtime failure in custom tag

An error occurred:
javax.servlet.ServletException: runtime failure in custom tag 'process'
     at jsp_compiled._tools._property._propset_create._jspService(_propset_create.java:641)
     at weblogic.servlet.jsp.JspBase.service(JspBase.java:27)
     at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:208)
     at weblogic.servlet.internal.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:149)
     at com.beasys.commerce.foundation.flow.ServletDestinationHandler.handleDestination(ServletDestinationHandler.java:51)
     at com.beasys.commerce.foundation.flow.FlowManager.service(FlowManager.java:540)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:208)
     at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:1127)
     at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:1529)
     at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:137)
     at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)

I just started getting this error after a year in production environment without any problems. Did you every find out what caused this or better yet how to prevent this?
          Dan.

Is possible to write a custom tag inside another custom tag ??

Hi
I�m trying to reduce the time needed to code mi app presentation layer, it uses some custom tags with certain configuration, i would like to know if its possible to do something like this inside my custom tag doAfterBody().
public int doAfterBody() throws JspException {
          JspWriter writer=bodyContent.getEnclosingWriter();
          try {
               writer.print("<customTag:myAnotherTag someEspecificConfigurationParams="someEspecificValues"/>");
          } catch (IOException e) {
               pageContext.getServletContext().log("Error: "+e.getMessage());
          }return SKIP_BODY;
     }The goal is to simplify the jsp code because the configuration params for the custom tags (css styles and similar) are allways the same.
That don�t work, it simply prints <customTag:myAnotherTag/> in screen but the tag is not evaluated, i�ve tried too something like
public int doAfterBody() throws JspException {
          if (repeat) {
               JspWriter writer = bodyContent.getEnclosingWriter();
               try {
                    writer.print("<customTag:myAnotherTag/>");
               } catch (IOException e) {
                    pageContext.getServletContext().log("Error: " + e.getMessage());
               repeat = false;
               return EVAL_BODY_AGAIN;
          return SKIP_BODY;
     }And it doesn�t worked worked. Maybe using the taghandler classes and calls to the doAfterBody could make it work, but when you need to nest tags it could be a little hell of coupling calls, so before doing it i would like to know if what i want is possible. After reading some books i tought it could work because the stack of out objects, but i can�t make it work.
Another idea is to inherit from tagHandler and override some properties in the tags, but i don�t like the idea to much.
So, can anyone help me??
Thanks.

You cannot do that and I have listed out the reason and a possible solution in this post http://forum.java.sun.com/thread.jspa?threadID=697243 from yesterday.
cheers,
ram.

Simple question about custom tags really easy!!

I am trying to make my own custom tags, so far i have created simple one that have i use for heading or to set the page layout for a jsp page, My question is I want to make a custom tag with a body , with a start and end tag can anybody give a simple example of a custom tag which has a body.
I do not mean write me a tag i mean what could a tag with a body be used for? Can you give me some example of what a tag of this kind could do?

Thanks having read that and some other pages i have another question:
would it be possible to put the following code into a custom tag so that i can pass in a list and have it output it to a table?
<TABLE >
<%
out.println("<TABLE >\n" +
                "<TR BGCOLOR=\"#FFDDAA\">\n" +
                " <TH>ID Number\n" +
                " <TH>Artist\n"
Iterator it = pricePassed.getpricePassed().iterator();
while( it.hasNext() ){
   MySite.VideoBean vids = (MySite.VideoBean) it.next();
   out.println( "<TR>\n" +
               "<TD><Center><B>" + vids.getRecId() + "</TD>" +
                "<TD><Center><B>" + vids.getArtist() + "</TD>"
</TD></TR>\n" );
%></TABLE>At the moment i use the above in a jsp to put data into a table, would it be a massive task to undertake to put into a custom tag?

Problem Calling Query in Custom Tag

I am using this code to call a custom tag called
broadcast.cfm
<cf_broadcast query="fe" orgID = "4">
The query fe is an included file on my site and is available
to the page I'm calling the custom tag from.
In the custom tag I am referencing the query like:
<cfloop query="#attributes.query#">
but I keep getting this error:
"The value of the attribute query, which is currently "fe",
is invalid. "
I must be missing something really simple here but can't
figure out what.

quote:
Originally posted by:
-==cfSearching==-
rdk8487 wrote:
> In the custom tag I am referencing the query like:
> <cfloop query="#attributes.query#">
> but I keep getting this error:
> "The value of the attribute query, which is currently
"fe", is invalid. "
It is a scoping problem. The query is defined in the calling
page. To access it by name, within the custom tag, use the "caller"
scope.
<cfloop query="caller.#attributes.nameOfTheQuery#">
If the query object is passed to the custom tag via an
attribute you shouldn't need the caller scope. See attached sample.

Variable declaration in the custom tag

Hey,
I am using JSP2.0 to write a custom tag. and I need to declare a script variable in my tag so that it can be referenced in a jsp file. At the beginning, I used name-given and my tag works as it supposed to do. But I don't like to make the variable name hard-coded in my tag so that I changed name-given to name-from-attribute as folllows:
<jsp:directive.variable name-from-attribute="var" alias="local" variable-class="java.util.ArrayList" scope="AT_END"/>
<jsp:scriptlet>
out.println(local.getClass().getName());
</jsp:scriptlet>
According to my understanding, variable "local" should be able to be referenced in my tag file and when the tag created in a jsp file
<tags:myTag var="myTest" />
the variable myTest should be able to be referenced in this jsp file too. But whenever I try this in jsp: out.println(myTest.getClass().getName());
I always got this error" myTest cannot be resolved"
I am totally stuck here. Someone could please give me some hints? thanks a lot!

Do you have a getter method to match that property?
Post some example code - what does your tld define for this property, and what get/set methods have you defined for it?

Commenting out custom tag

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