To those interested:
I followed the rabbit trail implied by Craig's response, and have discovered that in
fact there is an issue when Struts attempts to register its local DTD in the
initDigester method. However, I believe it may be due to a bug in the Struts code, not
Enhydra's class loader. The class loader implicitly used by the code in
ActionServlet.initDigester:
URL url = this.getClass().getResource(registrations[i+1]);
is "org.apache.tomcat.core.ServletClassLoader". I didn't pursue this angle terribly
far other than to intuit that it wasn't the class loader I expected.
Making a short story long, I figured that the "getResource" method on the servlet
context was the appropriate method to use, I changed the relevant section in
initDigester to:
// Register our local copy of the DTDs that we can find
for (int i = 0; i < registrations.length; i += 2) {
URL url;
try {
url =
getServletConfig().getServletContext().getResource(registrations[i+1]);
}
catch (java.net.MalformedURLException e) {
url = null;
}
if (url != null)
digester.register(registrations[i], url.toString());
}
This seems to fix the problem, though I can't say for sure what ill side effects it
could have. My guess is that one can't assume that the class loader of the servlet
class itself (at least, perhaps, while it's "init" method is still running) is the
same as that of the web application as a whole. Consequently, the standard servlet
getResource method is appropriate because the classpath of the class loader being used
behind the scenes of that method is the one to which the WEB-INF/lib stuff and
WEB-INF/classes directories have been added.
Thanks,
Donnie
>>> [EMAIL PROTECTED] 02/12/01 03:01PM >>>
Lee Hall wrote:
> We've been using the Tomcat 3.2 that is integrated with NetBeans to do
> our Struts development. Our test deployment server (AIX 4.3 with the
> IBM 1.2.2 JVM) is running a vanilla Tomcat3.2.1. Neither of these
> environments has any problem with the subject of this message. Our
> pre-production server (AIX 4.3 with the IBM 1.2.2 JVM) is running
> Enhydra 3.1 and fails initialization due to the validation done by
> ActionServlet. We've tried forcing Xerces 1.2 in Enhydra, but Enhydra
> persists in it's attempt to validate using the network URL instead of
> the local resource. I hacked ActionServlet.initDigester() to turn off
> validation and that got us by - but I know it's the wrong way to deal
> with this. In spite of the Barracuda project, I would hope that the
> Enhydra team would want to be completely Tomcat-compatible (which I
> think includes Struts compatibility). Still, it was easier to "fix"
> the ActionServlet than to fingure out why we are having this problem
> with Enhydra. I know, I know... I should have extended ActionServlet
> to override instead of butchering my clean Struts - but the question
> remains regarding why this seeming incompatibility exists. Could
> somebody give me a clue? - Lee
As you can see from the source code in ActionServlet, Struts attempts to
register its local copy of the DTD in the initDigester() method. It
uses Class.getResource() to actually acquire a URL for reading the
contents of the DTD, which is stored as a resource in the "struts.jar"
file. If the web application class loader in Enhydra has problems
implementing this method correctly, you could encounter the symptom that
you report (trying to go across the network to grab the DTD).
Craig McClanahan
-----------------------------------------------------------------------------
To unsubscribe from this mailing list, send email to [EMAIL PROTECTED]
with the text "unsubscribe enhydra" in the body of the email.
If you have other questions regarding this mailing list, send email to
the list admin at [EMAIL PROTECTED]
