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.
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-2.0.jar) together with the SLF4J bridge (log4j-slf4j-impl-2.0.jar) should never be attempted as it will cause events to endlessly be routed between SLF4J and Log4j 2.