2.12.1 (2019-08-06)

This release contains bugfixes and minor enhancements.

This release improves the performance of capturing location information, makes log4j-core optional in the log4j 1.2 bridge, and explicitly removes LoggerContext references from components that keep track of them when the LoggerContext is shut down. More details on the new features and fixes are itemized below.

Due to a break in compatibility in the SLF4J binding, Log4j now ships with two versions of the SLF4J to Log4j adapters. log4j-slf4j-impl should be used with SLF4J 1.7.x and earlier and log4j-slf4j18-impl should be used with SLF4J 1.8.x and later.

Note that the XML, JSON and YAML formats changed in the 2.11.0 release: they no longer have the timeMillis attribute and instead have an Instant element with epochSecond and nanoOfSecond attributes.

The Log4j 2.12.1 API, as well as many core components, maintains binary compatibility with previous releases.

Log4j 2.12.1 requires a minimum of Java 8 to build and run. Log4j 2.3 was the last release that supported Java 6 and Log4j 2.11.2 is the last release to support Java 7.

Basic compatibility with Log4j 1.x is provided through the log4j-1.2-api component, however it does not implement some of the very implementation specific classes and methods. The package names and Maven groupId have been changed to org.apache.logging.log4j to avoid any conflicts with Log4j 1.x.

For complete information on Apache Log4j 2, including instructions on how to submit bug reports, patches, or suggestions for improvement, see the Apache Log4j 2 website.