The Simple Logging Facade for Java or (SLF4J) is intended to serve as a simple facade for various logging APIs allowing to the end-user to plug in the desired implementation at deployment time. SLF4J also supports a bridging legacy APIs as well as a source code migration tool.
SLF4J API offers an advanced abstraction of various logging systems, including JDK 1.4 logging, log4j and logback. Features include parameterized logging and MDC support.
Logging systems can either choose to implement the the SLF4J interfaces directly, e.g. logback or SimpleLogger. Alternatively, it is possible (and rather easy) to write SLF4J adapters for a given API implementation, e.g. Log4jLoggerAdapter or JDK14LoggerAdapter..
Logback is intended as a successor to the popular log4j project. It was designed by Ceki Gülcü, the founder of log4j. It builds upon experience gained in building industrial-strength logging systems going back as far as 1999.
Logback's basic architecture is sufficiently generic so as to apply under different circumstances. At present time, logback is divided into three modules, logback-core, logback-classic and logback-access.
The logback-core module lays the groundwork for the other two modules. The logback-classic module can be assimilated to a significantly improved version of log4j. Moreover, logback-classic natively implements the SLF4J API so that you can readily switch back and forth between logback and other logging systems such as log4j or JDK14 Logging.
The logback-access module integrates with Servlet containers, such as Tomcat and Jetty, to provide HTTP-access log functionality. Note that you could easily build your own module on top of logback-core.
Lilith is a logging and access event viewer for the Logback logging framework.
It has features comparable to Chainsaw, a logging event viewer for log4j. This means that it can receive logging events from remote applications using Logback as their logging backend.
It uses files to buffer the received events locally, so it is possible to keep vast amounts of logging events at your fingertip while still being able to check only the ones you are really interested in by using filtering conditions.
As of V0.9.35, Lilith does also support LOG4j and java.util.logging XML file import.
Lilith V0.9.37 has been released on 2009-11-11!
Changing Log4j logging levels dynamically
Simple problem and may seem oh-not-so-cool. Make the log4j level dynamically configurable. You should be a able to change from DEBUG to INFO or any of the others. All this in a running application server.