This won't work since, all jar files in commons/lib, commons/endorsed, and commons/classes are all visible to the tomcat's "commons" classloader. So, there is no difference whether we put the xerces jar files in "lib" or "endorsed", the one from webapps will be skipped.
I think the question boiled down to, if we have Xerces on both "endorsed" and "webapps", which one should be used? For tomcat, I would thought that the order for class searching will be "webapps", "shared", "commons" (including "endorsed"), then "system". I believed tomcat put "endorsed" before "system" is to follows the "endorsed classloading spec.". But I also believed forcing delegate model for xerces and xalan maybe overkill? Indeed, the tomcat's "class-loader-howto" document also indicated that the one from webapps should be used instead. Frankly speaking, I'm no expert on these topics, so please feel free to correct me if I mis-understanding anything here. Thanks. William. -----Original Message----- From: Shapira, Yoav [mailto:[EMAIL PROTECTED] Sent: Thursday, October 09, 2003 12:44 PM To: Tomcat Developers List Subject: RE: Webapp classloader question. Howdy, Tomcat 4.1.x implements the endorsed classloader spec. It's compliant with the Servlet Specification v2.3. What you can do if you want your webapp to use the latest xerces/JAXP, is: - Move $CATALINA_HOME/common/endorsed/* to $CATALINA_HOME/common/lib - Put your later xerces etc. in WEB-INF/lib as you've been doing. Yoav Shapira Millennium ChemInformatics >-----Original Message----- >From: Lee, William [mailto:[EMAIL PROTECTED] >Sent: Thursday, October 09, 2003 12:38 PM >To: [EMAIL PROTECTED] >Subject: Webapp classloader question. > > >Hi all, > >I'm not sure if this message reaches you guys yet, so here it go again. >Sorry for any inconvenience if you receiving this message twice. > >Thanks. >William. > >-----Original Message----- >From: Lee, William [mailto:[EMAIL PROTECTED] >Sent: Tuesday, October 07, 2003 3:55 PM >To: '[EMAIL PROTECTED]' >Subject: Webapp classloader question. > > >Hi all, > >When moving from tomcat 4.0.x to 4.1.x, we discovered that the >WebappClassLoader.java had been changed such that all classes from >"org.apache.xerces" and "org.apache.xalan" are forced to be loaded using >the >delegate model first, before looking into the webapp directory. This seems >to related to the JDK 1.4 support of the xml and xslt parser. > >However, after a long conversation with the Sun's Java engineer, he point >out that, even JDK 1.4 shipped with the default xml and xslt parser, >application server and servlet container should continue to use the one >provided from the webapp directory as described in the servlet spec. 2.3. > >Could someone please hint some lights on why tomcat 4.1.x decided to >enforce the delegate model for these two packages? > >(The reason I'm asking is that, we try to use the latest Xerces in our >webapps, and since it always look and found the one from common/endorsed >directory, our latest version will always be skipped.) > >Thanks in advance for your help. >William. > >Join us at Cognos' biggest event of the year Enterprise 2003, The Cognos >Business Forum. Taking place in over 25 cities around the world, it's an >opportunity for Business and IT leaders to learn about strategies for >driving performance. Visit http://www.cognos.com/enterprise03 for more >details. > >This message may contain privileged and/or confidential information. If >you >have received this e-mail in error or are not the intended recipient, you >may not use, copy, disseminate or distribute it; do not open any >attachments, delete it immediately from your system and notify the sender >promptly by e-mail that you have done so. Thank you. This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Join us at Cognos' biggest event of the year Enterprise 2003, The Cognos Business Forum. Taking place in over 25 cities around the world, it's an opportunity for Business and IT leaders to learn about strategies for driving performance. Visit http://www.cognos.com/enterprise03 for more details. This message may contain privileged and/or confidential information. If you have received this e-mail in error or are not the intended recipient, you may not use, copy, disseminate or distribute it; do not open any attachments, delete it immediately from your system and notify the sender promptly by e-mail that you have done so. Thank you.
