apache-log4j2

Fast and flexible logging library for Java

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 fixing some inherent problems in Logback's architecture. Log4J is an open source library based on the work of many authors. It allows the developer to control which log statements are output with arbitrary granularity. It is fully configurable at runtime using external configuration files. Best of all, Log4J has a gentle learning curve. Beware: judging from user feedback, it is also quite addictive. See also <https://github.com/apache/logging-log4j2>.