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Log4j 2 to SLF4J Adapter

The Log4j 2 to SLF4J Adapter allows applications coded to the Log4j 2 API to be routed to SLF4J. Use of this adapter may cause some loss of performance as the Log4j 2 Messages must be formatted before they can be passed to SLF4J. With Log4j 2 as the implementation these would normally be formatted only when they are accessed by a Filter or Appender.


The Log4j 2 to SLF4J adapter is dependent on the Log4j 2 API and the SLF4J API. For more information, see Runtime Dependencies.


Include this jar, the SLF4J jar(s) and an SLF4J logging implementation jar together. Configure the logging implementation as required.

Use of the SLF4J adapter (log4j-to-slf4j-2.x.jar) together with the SLF4J bridge (log4j-slf4j-impl-2.x.jar) should never be attempted as it will cause events to endlessly be routed between SLF4J and Log4j 2.