Author: seb Date: Fri Jan 12 13:51:12 2007 New Revision: 1202 Modified: logback/trunk/logback-site/src/site/fml/faq.fml Log: added questions on JCL interception Modified: logback/trunk/logback-site/src/site/fml/faq.fml ============================================================================== --- logback/trunk/logback-site/src/site/fml/faq.fml (original) +++ logback/trunk/logback-site/src/site/fml/faq.fml Fri Jan 12 13:51:12 2007 @@ -15,6 +15,11 @@ </question> <answer> + <p> + The Jetty application server uses SLF4J for its internal + logging. Here are the required steps to install logback as + SLF4J's underlaying implementation. + </p> <p> A few jars must be present in the <em>JETTY_HOME/lib</em> @@ -30,15 +35,14 @@ <p> Logback's own jars must also be present, namely <em>logback-core-VERSION.jar</em> and - <em>logback-classic-VERSION.jar</em> . + <em>logback-classic-VERSION.jar</em>. </p> <p> To configure logback-classic, a file called - <em>logback.xml</em> should be placed at the root - directory of Jetty, that is the <em>JETTY_HOME</em> - directory or in the <em>JETTY_HOME/resources</em> directory, - depending on your classpath settings. You can find configuration samples in the + <em>logback.xml</em> should be placed in the + <em>JETTY_HOME/resources</em> directory. + You can find configuration samples in the <em>examples/src/chapter4/conf/</em> directory, in the distribution of logback. </p> @@ -68,6 +72,75 @@ </faq> + <faq id="intercept_calls_tomcat"> + + <question> + How can I intercept JCL calls in Tomcat? + </question> + + <answer> + <p> + When a dependency of your webapp logs using Jakarta Commons Logging + (for example Struts), you can intercept these calls and redirect them to logback. + </p> + <p> + This can be done by using <em>jcl104-over-slf4j.jar</em>, a module + that is shipped with <a href="http://www.slf4j.org">SLF4J</a>. + </p> + <p> + If you have only one webapp, its <em>WEB-INF/lib</em> directory should already + contain the logback jars, namely <em>logback-core-VERSION.jar</em>, + <em>logback-classic-VERSION.jar</em> and <em>slf4j-api-VERSION.jar</em>. + A logback configuration file, named + <em>logback.xml</em> should be placed in the <em>WEB-INF/classes/</em> + directory. + </p> + <p> + You now need to add <code>jcl104-over-slf4j.jar</code> + to your <em>WEB-INF/lib</em> directory and remove + <code>commons-logging-1.0.4.jar</code>. The logging that used to + be directed to JCL should now be handled by logback. + </p> + + <p> + In case several webapps share the logback jars, you might place the + previously mentionned jars in the <em>common/lib/</em> directory of + your Tomcat installation. The <em>logback.xml</em> file should then + be placed in <em>common/classes</em>. + </p> + </answer> + </faq> + + <faq id="intercept_calls_jetty"> + + <question> + How can I intercept JCL calls in Jetty ? + </question> + + <answer> + <p> + Using logback as the logging implementation of choice for frameworks + depending on JCL can also be done in Jetty. + </p> + <p> + In case you have only one webapp, the required steps are exactly the same + as <a href="#intercept_calls_tomcat">those needed in Tomcat</a>. + </p> + <p> + In case several webapps share the logback jars, you might place the + necessary jars in the <em>lib/</em> directory of + your Jetty installation. The <em>logback.xml</em> file should then + be placed in the <em>resources/</em> directory. + </p> + <p> + However, due to <a href="http://docs.codehaus.org/display/JETTY/Classloading"> + Jetty's internal Classloading mechanism</a>, the <em>logback-classic-VERSION.jar</em> + and <em>slf4j-api-VERSION.jar</em> files need to be in your webapps, too. They + should be placed in the <em>WEB-INF/lib/</em> directory of your webapps. + </p> + </answer> + </faq> + </part> </faqs> </body>