Rename zip to jar and put it in lib Jan On Wed, 19 Dec 2001, David Morsberger wrote:
> I ran into a similar problem today that I can not explain while upgrading to > tomcat 3.3. The JSP we created accesses a bean that uses the oracle 1.2 JDBC > driver, classes12.zip. > > I placed the Oracle classes12.zip file in the myapp/WEB-INF/lib directory > and then I got the NoClassDef exception. > > I unjar'd the .zip file in the myapp/WEB-INF/lib directory and still got the > NoClassDef exception. > > I unjar'd the .zip file in the myapp/WEB-INF/classes directory and it > worked. > > Where should the .zip file be placed for inclusion in a bean? I recycled > Tomcat after every attempt. > > > From: "Lauer, Oliver" <[EMAIL PROTECTED]> > > Reply-To: "Tomcat Users List" <[EMAIL PROTECTED]> > > Date: Mon, 17 Dec 2001 18:56:34 +0100 > > To: "'Tomcat Users List'" <[EMAIL PROTECTED]> > > Subject: AW: Classloader question > > > > But why wasn't the class found in myapp/WEB-INF/lib ? Sorry, but I don't > > understand that !? > > > >> AXA eSolutions GmbH > >> AXA Konzern AG Germany > >> Oliver Lauer > >> Web Architect > >> W�rthstra�e 34 > >> D-50668 K�ln > >> Germany > >> Tel.: +49 221 148 31277 > >> Fax: +49 221 148 43963 > >> Mobil: +49 179 59 064 59 > >> e-Mail: [EMAIL PROTECTED] > >> _____________________________ > >> > > > > > > -----Urspr�ngliche Nachricht----- > > Von: Craig R. McClanahan [mailto:[EMAIL PROTECTED]] > > Gesendet: Montag, 17. Dezember 2001 18:50 > > An: Tomcat Users List > > Betreff: Re: Classloader question > > > > > > > > > > On Mon, 17 Dec 2001, Heikki Doeleman wrote: > > > >> Date: Mon, 17 Dec 2001 13:06:21 +0100 > >> From: Heikki Doeleman <[EMAIL PROTECTED]> > >> Reply-To: Tomcat Users List <[EMAIL PROTECTED]> > >> To: "'[EMAIL PROTECTED]'" <[EMAIL PROTECTED]> > >> Subject: Classloader question > >> > >> Hi everyone, > >> > >> trying to make a web application work using Tomcat 4.0.1 I found the > >> following behaviour, which I don't quite understand: > >> > >> my application uses a library called xhive.jar > >> > >> - putting xhive.jar in [catalina]/common/lib > >> This works fine, as expected > >> > >> > >> - putting it in [myapp]/WEB-INF/lib > >> Causes a ClassDefNotFoundError. I don't know why this is so, it does not > >> seem to conform to the description in class-loader-howto.html. However I > > did > >> see someone saying that in that directory, only .class files are added to > >> the classpath, not .jars > >> (http://www.geocrawler.com/archives/3/193/2000/12/0/4841079/). > >> > >> > >> - putting it in both those places > >> Causes a ClassCastException ?? Something seems to go terribly wrong when > > the > >> jar is placed in both those directories. > >> > >> Can anyone explain more about this? I'd like to know exactly how this > > works, > >> especially I'd like to know why classes from a jar in my application's > >> WEB-INF/lib apparently are not loaded. > >> > > > > This has been discussed numerous times in the archives, but the short > > answer is this: it is fundamental to the way Java class loaders work. > > The key issues: > > > > * A class named "a.b.c.Foo" loaded from two different > > class loaders is ***not*** the same class, even if the > > bytecodes are identical. Trying to assign from one to > > the other will give you ClassCastException errors. > > > > * The "new" operator in Java tries to load the specified > > class from the same classloader that loaded the class > > containing this code. If the class of that name has > > already been loaded by the "other" classloader, you > > again get ClassNotFoundException errors. > > > > * Class loader hierarchies can delegate "up" but not "down". > > Thus, it's also easy to have the "new" operator cause > > ClassNotFoundException errors, even though you "know" that > > the class is there. > > > > Moral of the story -- you are *always* best off having one and only one > > copy of a class visible to a web application. There's ways to deal with > > some of these issues, but they get pretty intricate. > > > >> Thanks > >> Heikki Doeleman > >> > > > > Craig McClanahan > > > > > > -- > > To unsubscribe: <mailto:[EMAIL PROTECTED]> > > For additional commands: <mailto:[EMAIL PROTECTED]> > > Troubles with the list: <mailto:[EMAIL PROTECTED]> > > > > > > ------------------------------------------------------------------------------ > > Aus Rechts- und Sicherheitsgruenden ist die in dieser E-Mail gegebene > > Information nicht rechtsverbindlich. Eine rechtsverbindliche Bestaetigung > > reichen wir Ihnen gerne auf Anforderung in schriftlicher Form nach. Beachten > > Sie bitte, dass jede Form der unautorisierten Nutzung, Veroeffentlichung, > > Vervielfaeltigung oder Weitergabe des Inhalts dieser E-Mail nicht gestattet > > ist.Diese Nachricht ist ausschliesslich fuer den bezeichneten Adressaten oder > > dessen Vertreter bestimmt. Sollten Sie nicht der vorgesehene Adressat dieser > > E-Mail oder dessen Vertreter sein, so bitten wir Sie, sich mit dem Absender > > der E-Mail in Verbindung zu setzen. > > ---------------------------- > > For legal and security reasons the information provided in this e-mail is not > > legally binding. Upon request we would be pleased to provide you with a > > legally binding confirmation in written form. Any form of unauthorised use, > > publication, reproduction, copying or disclosure of the content of this e-mail > > is not permitted. This message is exclusively for the person addressed or > > their representative. If you are not the intended recipient of this message > > and its contents, please notify the sender immediately. > > > > ============================================================================== > > > > > > -- > > To unsubscribe: <mailto:[EMAIL PROTECTED]> > > For additional commands: <mailto:[EMAIL PROTECTED]> > > Troubles with the list: <mailto:[EMAIL PROTECTED]> > > > > > -- > To unsubscribe: <mailto:[EMAIL PROTECTED]> > For additional commands: <mailto:[EMAIL PROTECTED]> > Troubles with the list: <mailto:[EMAIL PROTECTED]> > Jan K. Labanowski | phone: 614-292-9279, FAX: 614-292-7168 Ohio Supercomputer Center | Internet: [EMAIL PROTECTED] 1224 Kinnear Rd, | http://www.ccl.net/chemistry.html Columbus, OH 43212-1163 | http://www.osc.edu/ -- To unsubscribe: <mailto:[EMAIL PROTECTED]> For additional commands: <mailto:[EMAIL PROTECTED]> Troubles with the list: <mailto:[EMAIL PROTECTED]>
