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

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.

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 …

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 …

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

The latest log4j version, including full-source code, class files and documentation can be found at http://logging.apache.org/log4j/2.x/index.html. Inserting log statements into code is a low-tech …

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 JUL-to-Log4j API and Log4j 1-to-Log4j API will no longer be able to modify the configuration of Log4j Core by default. If such a functionality is required, it must be explicitly enabled.