Bug 37029 - TLD Validation error for HTML "param" element
Summary: TLD Validation error for HTML "param" element
Status: RESOLVED FIXED
Alias: None
Product: Taglibs
Classification: Unclassified
Component: Standard Taglib (show other bugs)
Version: nightly
Hardware: Other other
: P2 major with 3 votes (vote)
Target Milestone: ---
Assignee: Tomcat Developers Mailing List
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2005-10-11 21:23 UTC by Michał Borowiecki
Modified: 2005-12-17 12:05 UTC (History)
0 users


Attachments
Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Michał Borowiecki 2005-10-11 21:23:13 UTC 
TLD Validator reports errors when it encounters the html "param" element.

Example:
<?xml version="1.0"?>
<html
    xmlns:jsp="http://java.sun.com/JSP/Page"
    xmlns:jstlc="http://java.sun.com/jsp/jstl/core"
    xmlns:jstlf="http://java.sun.com/jsp/jstl/fmt">

    <jstlc:if test="${true}">
        <applet code="some.package.SomeApplet.class" archive="applet.jar"
width="1" height="1">
            <param name="tx" value="${'blah'}"/>
        </applet>
    </jstlc:if>
</html>

causes the following error:

org.apache.jasper.JasperException: <h3>Validation error messages from
TagLibraryValidator for c</h3><p>4: Invalid use of "param" tag outside
legitimate parent tag</p><h3>Validation error messages from TagLibraryValidator
for fmt</h3><p>4: &lt;param&gt; outside &lt;message&gt;</p>
	org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:50)
	org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:407)
	org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:72)
	org.apache.jasper.compiler.Validator.validateXmlView(Validator.java:1549)
	org.apache.jasper.compiler.Validator.validate(Validator.java:1495)
	org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:157)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:286)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:267)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:255)
	org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:556)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:293)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
Comment 1 Kris Schneider 2005-10-11 22:05:23 UTC 
Try adding the XHTML namespace to the <html> element:

<html
    xmlns="http://www.w3.org/1999/xhtml"
    xmlns:jsp="http://java.sun.com/JSP/Page"
    xmlns:jstlc="http://java.sun.com/jsp/jstl/core"
    xmlns:jstlf="http://java.sun.com/jsp/jstl/fmt">
...
Comment 2 Jan Luehe 2005-12-10 01:17:16 UTC 
The html <param> is being treated incorrectly as an <fmt:param> tag,
because of this code in JstlBaseTLV:

    protected boolean isTag(String tagUri,
                            String tagLn,
                            String matchUri,
                            String matchLn) {
        if (tagUri == null
                || tagLn == null
                || matchUri == null
                || matchLn == null)
            return false;

        if (tagUri.length() > matchUri.length()) {
            return (tagUri.startsWith(matchUri)
                    && tagLn.equals(matchLn));
        } else {
            return (matchUri.startsWith(tagUri)
                    && tagLn.equals(matchLn));
        }

In the test case, isTag() is invoked with these args:

  tagUri=""
  tagLn="param"
  matchUri="http://java.sun.com/jsp/jstl/fmt"
  matchLn="param"

which means the "else" will return TRUE, since any string starts with
the empty string!

The fix is to return FALSE if the "tagUri" param is NULL or the EMPTY
string, as shown in these diffs:

--- JstlBaseTLV.java    8 Dec 2005 01:21:24 -0000
+++ JstlBaseTLV.java    10 Dec 2005 00:01:32 -0000
@@ -210,6 +210,7 @@
                            String matchUri,
                            String matchLn) {
        if (tagUri == null
+                || tagUri.length() == 0
                || tagLn == null
                || matchUri == null
                || matchLn == null)
Comment 3 Pierre Delisle 2005-12-17 21:05:11 UTC 
Applied Jan's patch. Thanks Jan!