Craig, who controls loading and reloading jasper class loaders? and how is it being managed? I'm also working on a project where I need to auto-reload Java classes at runtime. If you could point me to any kind of documentation, that'd be greatly appreciated.
thanks, Adrian --- "Craig R. McClanahan" <[EMAIL PROTECTED]> wrote: > > > On Wed, 31 Jul 2002, Babu Wisor wrote: > > > Date: Wed, 31 Jul 2002 10:15:08 -0700 (PDT) > > From: Babu Wisor <[EMAIL PROTECTED]> > > Reply-To: Tomcat Developers List > <[EMAIL PROTECTED]> > > To: Tomcat Developers List > <[EMAIL PROTECTED]> > > Cc: [EMAIL PROTECTED] > > Subject: Re: how to do auto update/reload of a > class? > > > > Hi All, > > Does anyone have any thoughts as to how to > auto > > re-load the classes, which have been loaded into > JVM > > using Custom Class loader? I tried writing custom > > class loader and loaded all the classes, but don't > > know how to re-load the same class, if it has been > > modified (re-compiled) without shutting down JVM, > > similar to JSP engine, where if we put updated JSP > > file, it picks up the new file. > > > > Jasper does this by creating a class loader for each > page, and throwing > away the class loader when the page is recompiled. > The JVM doesn't let > you do things any other way. > > > Note: I learnt that, we need to recreate new class > > loader and load all the classes again, but don't > know > > exactly how to apply that technique in the system. > Any > > help is greatly appreciated. > > > > My personal advice, after living through (barely :-) > getting a class > loader that would reload a webapp to work, is to > abandon this approach > unless you are just doing it for fun and learning > how class loading works. > You are going to find that the fundamental > architecture of Java isn't > really oriented towards incremental replacement of > classes (although there > is a little bit better support in 1.4). > > > Thank you, > > Babu > > Craig > > > --- Ian Darwin <[EMAIL PROTECTED]> wrote: > > > On July 28, 2002 10:32 pm, you wrote: > > > > Does anyone know, how to do auto update of > > > classes > > > > into the JVM? I > > > > tried to write my own custom class loader, and > > > loaded > > > > all the classes > > > > through it, however if I put new updated > class, it > > > > won't reload the > > > > class again. Have anyone tried this before? > Help > > > is > > > > very much > > > > appreciated. > > > > > > This better asked on an advanced-java list; not > > > tomcat specific. > > > > > > For all the cleverness of Java's dynamic loading > > > mechanism (ClassLoader, > > > Class.forName, newInstance(), etc.), there is no > > > published API for unloading or reloading. > > > They just didn't think of it in time, perhaps. > > > > > > What I think Tomcat and others do is basically > to > > > manage the class loader for each Context > > > (which has to be separate from the CL for each > other > > > Context for configuration > > > and security reasons anyway) in such a way that > you > > > can delete > > > it (un-reference it) and assign a new one and > reload > > > the classes > > > for the given Context. > > > > > > -- > > > To unsubscribe, e-mail: > > > > <mailto:[EMAIL PROTECTED]> > > > For additional commands, e-mail: > > > <mailto:[EMAIL PROTECTED]> > > > > > > > > > __________________________________________________ > > Do You Yahoo!? > > Yahoo! Health - Feel better, live better > > http://health.yahoo.com > > > > -- > > To unsubscribe, e-mail: > <mailto:[EMAIL PROTECTED]> > > For additional commands, e-mail: > <mailto:[EMAIL PROTECTED]> > > > > > > > -- > To unsubscribe, e-mail: > <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: > <mailto:[EMAIL PROTECTED]> > __________________________________________________ Do You Yahoo!? Yahoo! Health - Feel better, live better http://health.yahoo.com -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
