Apache Logging Services
The Apache Logging Services Project creates and maintains open-source software related to the logging of application behavior and released at no charge to the public.
Log4j 2 provides both a portable logging API and implementation for Java with significant improvements over its predecessor, Log4j 1.x.
Apache Log4j™ for Kotlin
Kotlin API for Log4j 2.
Apache Log4j™ for Scala
Scala API for Log4j 2.
Apache log4cxx is a logging framework for C++ patterned after log4j.
A GUI based log viewer. Chainsaw is a companion application to log4j written by members of the log4j development community.
Apache Log4j Audit
Audit logging framework built upon Apache Log4j 2.