Simple Logging Facade for Java (SLF4J)

The Simple Logging Facade for Java or (SLF4J) serves as a simple facade or abstraction for various logging frameworks, e.g. java.util.logging, log4j and logback, allowing the end user to plug in the desired logging framework at deployment time.

Before you start using SLF4J, we highly recommend that you read the two-page SLF4J user manual.

Note that SLF4J-enabling your library implies the addition of only a single mandatory dependency, namely slf4j-api.jar. If no binding is found on the class path, then SLF4J will default to a no-operation implementation.

In case you wish to migrate your Java source files to SLF4J, consider our migrator tool which can migrate your project into SLF4J in minutes.

In case an externally-maintained component you depend on uses a logging API other than SLF4J, such as commons logging, log4j or java.util.logging, have a look at SLF4J's binary-support for legacy APIs.

Projects depending on SLF4J

Here is a non-exhaustive list of projects known to depend on SLF4J, in alphabetical order:

Apache ActiveMQ Apache Archiva Apache Camel Apache Directory Apache FTPServer Apache Geronimo Apache Graffito Apache Jackrabbit Apache Mina Apache Qpid Apache ServiceMix	Apache Sling Apache Solr Apache Tapestry Apache Wicket Aperture Apogee Artifactory AsyncWeb Bitronix DbUnit Display tag	Ehcache Gradle GreenMail GumTree H2 Database HA-JDBC Hibernate Igenko Jabsorb Jetty v6 jLynx
GMaven JMesa JODConverter JTrac JWebUnit 2.x JQuantLib LIFERAY Lift log4jdbc Magnolia MRCP4J	Mindquarry Mugshot Mule Nexus Novocode NetCDF OpenMeetings OpenRDF Penrose PZFileReader Quartz Scheduler	QuickFIX/J Sonar SMSJ Spring-OSGi SpringSource dm Server™ StreamBase TimeFinder WTFIGO YASL Xooctory XWiki