Apache Log4j is a versatile, industrial-grade Java logging framework composed of an API, its implementation, and components to assist the deployment for various use cases.

Log4j is essentially composed of a logging API called Log4j API, and its reference implementation called Log4j Core. Log4j also bundles several logging bridges to enable Log4j Core consume …

Apache Log4j 2 is an upgrade to Log4j that provides significant improvements over its predecessor, Log4j 1.x, and provides many of the improvements available in Logback while …

You can manually download all published Log4j distributions, verify them, and see their licensing information by following the instructions in the Download page of Logging Services.

The table below contains links to the Javadoc API Documentation for the components you are most likely to use directly in code.

Apache Log4j is a versatile, industrial-grade Java logging framework composed of an API, its implementation, and components to assist the deployment for various use cases.

Apache Log4j 2 is an upgrade to Log4j that provides significant improvements over its predecessor, Log4j 1.x, and provides many of the improvements available in Logback while …

This page tries to cover the most prominent Log4j API features. Did you know that Log4j provides specialized APIs for Kotlin and Scala? Check out Log4j Kotlin and Log4j Scala projects for …

Logging implementations accept input from a single logging API of their preference; Log4j Core from Log4j API, Logback from SLF4J, etc. A logging bridge is a simple logging implementation …

The Log4j Core implementation fully supports both standard and custom levels. Similarly to the Log4j API usage, custom levels must be defined in a configuration file before they can be used.