[slf4j-user] Per Web App logging
Ceki Gülcü
listid at qos.ch
Wed Nov 22 23:05:26 CET 2006
How would the logger factory know in which context you are? (It won't have
access to any of HttpRequest/HttpRespons/Session/Servlet/etc.)
At 10:16 PM 11/22/2006, you wrote:
>That is an excellent point....
>But is there anything else that can be used as a key that would reduce the
>"complexity". Is all we care about a unique key to logging context name?
>
> h = new Hierarchy(new RootCategory(Level.DEBUG));
> ht.put(loggingContextName, h);
>
>
>If so can we use something like context.getServletContextName();
>This returns a string and I can capture it when app starts and pass it onto
>RepositorySelector....
>
>
>---javadoc----
>getServletContextName
>
>public java.lang.String getServletContextName()
>
> Returns the name of this web application corresponding to this
>ServletContext as specified in the deployment descriptor for this web
>application by the display-name element.
>
> Returns:
> The name of the web application or null if no name has been declared
>in the deployment descriptor.
> Since:
> Servlet 2.3
>---javadoc----
>
>
>
>Again, thanks a lot for your responses...
>
>
>Regards
>Amir
>
>
>
>
>
>-----Original Message-----
>From: user-bounces at slf4j.org [mailto:user-bounces at slf4j.org] On Behalf Of
>Ceki Gülcü
>Sent: Wednesday, November 22, 2006 4:07 PM
>To: User list for the slf4j project; 'User list for the slf4j project'
>Subject: Re: [slf4j-user] Per Web App logging
>
>Amir,
>
>Holding classloaders references as keys in a map that is references by a
>class located at the server level, will prevent your application from being
>garbage collected. There is no such problem with String references which
>the JNDI approach uses.
>
>HTH,
>
>At 10:59 PM 11/21/2006, Amir Mistric wrote:
> >Ceki
> >
> >After sending you the whole class (previous email) I looked over its code
> >again and I also looked over this url. http://www.qos.ch/logging/sc.jsp
> >
> >The only significant difference I saw was that hashtable (or a hashmap in
>my
> >case) was using a different key approach. In Log4JloggingRepository class
> >the key is the Thread.currentThread().getContextClassLoader() while in
> >JNDIRS is the JNDI env key. JNDIRS also doesn't have a way to pass in
>config
> >file but other than that why would JNDI approach be more portable than
> >http://wiki.jboss.org/wiki/Wiki.jsp?page=Log4jRepositorySelector ?
> >
> >Regards
> >Amir
> >
> >
> >
> >-----Original Message-----
> >From: user-bounces at slf4j.org [mailto:user-bounces at slf4j.org] On Behalf Of
> >Ceki Gülcü
> >Sent: Monday, November 20, 2006 5:21 PM
> >To: User list for the slf4j project
> >Subject: Re: [slf4j-user] Per Web App logging
> >
> >
> >
> >In the MyWebAppContextListener code you supplied, one can read:
> >
> > Log4JContextualRepositorySelector.addToRepository(pConfigFilePath);
> >
> >How is the addToRepository method defined?
> >
> >At 11:14 PM 11/20/2006, you wrote:
> > >Yes it is and all we did was to rename the MyRepositorySelector class
>that
> > >JBoss Wiki has. The code is the same as on
> > >http://wiki.jboss.org/wiki/Wiki.jsp?page=Log4jRepositorySelector
> > >
> > >Amir
> > >
> > >-----Original Message-----
> > >From: user-bounces at slf4j.org [mailto:user-bounces at slf4j.org] On Behalf Of
> > >Ceki Gülcü
> > >Sent: Monday, November 20, 2006 4:51 PM
> > >To: User list for the slf4j project
> > >Subject: Re: [slf4j-user] Per Web App logging
> > >
> > >
> > >Hi Amir,
> > >
> > >Is the Log4JContextualRepositorySelector class yours?
> > >
> > >At 09:55 PM 11/20/2006, you wrote:
> > > >Hi Ceki
> > > >
> > > >Thanks for the quick reply.
> > > >Here are my answers:
> > > >
> > > > >If you use the JNDI-based repository selector, you can place a single
> > > > >log4j.jar in the containers shared class loader. I am a little
> >surprised
> > > > >that you need to copy log4j.jar in each web-app. Can you please
> > >elaborate?
> > > >
> > > >Here is the URL we used to configure the RepositorySelector.
> > > >http://wiki.jboss.org/wiki/Wiki.jsp?page=Log4jRepositorySelector
> > > >We have about 10 web apps running on JBoss AS and the above solution
> >works.
> > > >Each web app has its own WEB-INF/lib/log4j.jar and WEB-INF/log4j.xml...
> > > >Also, each application has a class that implements
> >ServletContextListener.
> > > >
> > > >public final class MyWebAppContextListener implements
> > >ServletContextListener
> > > >{
> > > >
> > > > private ServletContext context = null;
> > > > // we cannot use Logger.getLogger until we initialize it...
> > > > private static Logger log;
> > > >
> > > >...
> > > >...
> > > >...
> > > >
> > > >In this class we call (in contextInitialized() method):
> > > >
> > > > this.context.log("Initializing Log4J...");
> > > > // Before using Log4J logging system, we must initialize it by
> > > >adding
> > > > // the webapp specific configuration to the repository.
> > > >
> > >Log4JContextualRepositorySelector.addToRepository(pConfigFilePath);
> > > > // note that we can't call Logger.getLogger() until
> > > > // Log4JContextualRepositorySelector.addToRepository() is
> >called.
> > > > // For all other classes in the webapp, you can call
> > > >Logger.getLogger()
> > > > // at any time.
> > > > log = Logger.getLogger(FindADocContextListener.class);
> > > >
> > > >That is it....
> > > >However this fails if we remove log4j.jar from WEB-INF/lib...
> > > >
> > > >
> > > >I do apologize if this question is gettting off topic
> > > >
> > > >Amir
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >-----Original Message-----
> > > >From: user-bounces at slf4j.org [mailto:user-bounces at slf4j.org] On Behalf
>Of
> > > >Ceki Gülcü
> > > >Sent: Monday, November 20, 2006 3:43 PM
> > > >To: User list for the slf4j project
> > > >Subject: Re: [slf4j-user] Per Web App logging
> > > >
> > > >Hi Amir,
> > > >
> > > >At 09:32 PM 11/20/2006, Amir Mistric wrote:
> > > > >Hello Everyone
> > > > >
> > > > >My company would like to try SLF4J as a replacement for Log4J.
> > > > >Currently we use JBoss AS 4.x and the problem we had was that we
>could
> > >not
> > > > >configure logging "per web application".
> > > > >We ended up using RepositorySelector trick in order to be able to
>have
> >a
> > > > >separate log4j.xml in every web application deployed.
> > > > >This approach, however, requires each web app to have a copy of
> >log4j.jar
> > > > >in its WEB-INF/lib......
> > > >
> > > >If you use the JNDI-based repository selector, you can place a single
> > > >log4j.jar in the containers shared class loader. I am a little
>surprised
> > > >that you need to copy log4j.jar in each web-app. Can you please
> >elaborate?
> > > >
> > > > >Recently we decided to create a shared library repository for all web
> > >apps
> > > > >we have.
> > > > >While this approach has reduced the "baggage" each web app had in its
> > > > >WEB-INF/lib we still have to use log4j.jar ....
> > > > >
> > > > >Our goal is simple. Have every web application running on the same
>app
> > > > >server have its own logging config file but share the single JAR (or
> > >jars).
> > > >
> > > >Not yet, but it's core feature planned in one of the next releases of
> > > >logback.
> > > >
> > > > >Can SLF4J accomplish this (using built in logback classic) for us?
> > > >
> > > >No, SLF4J is just a front for logback/jul/log4j/jcl. While SLF4J cannot
> > > >accomplish what you are asking, log4j can do so, and logback will in
>the
> > > >near future.
> > > >
> > > > >Thanks
> > > > >Amir
> > > >
> > > >--
> > > >Ceki Gülcü
> > > >Logback: The reliable, generic, fast and flexible logging framework for
> > > >Java.
> > > >http://logback.qos.ch
> > > >
> > > >_______________________________________________
> > > >user mailing list
> > > >user at slf4j.org
> > > >http://www.slf4j.org/mailman/listinfo/user
> > > >
> > > >_______________________________________________
> > > >user mailing list
> > > >user at slf4j.org
> > > >http://www.slf4j.org/mailman/listinfo/user
> > >
> > >--
> > >Ceki Gülcü
> > >Logback: The reliable, generic, fast and flexible logging framework for
> > >Java.
> > >http://logback.qos.ch
> > >
> > >_______________________________________________
> > >user mailing list
> > >user at slf4j.org
> > >http://www.slf4j.org/mailman/listinfo/user
> > >
> > >_______________________________________________
> > >user mailing list
> > >user at slf4j.org
> > >http://www.slf4j.org/mailman/listinfo/user
> >
> >--
> >Ceki Gülcü
> >Logback: The reliable, generic, fast and flexible logging framework for
> >Java.
> >http://logback.qos.ch
> >
> >_______________________________________________
> >user mailing list
> >user at slf4j.org
> >http://www.slf4j.org/mailman/listinfo/user
> >
> >_______________________________________________
> >user mailing list
> >user at slf4j.org
> >http://www.slf4j.org/mailman/listinfo/user
>
>--
>Ceki Gülcü
>Logback: The reliable, generic, fast and flexible logging framework for
>Java.
>http://logback.qos.ch
>
>_______________________________________________
>user mailing list
>user at slf4j.org
>http://www.slf4j.org/mailman/listinfo/user
>
>_______________________________________________
>user mailing list
>user at slf4j.org
>http://www.slf4j.org/mailman/listinfo/user
--
Ceki Gülcü
Logback: The reliable, generic, fast and flexible logging framework for Java.
http://logback.qos.ch
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