--- layout: post status: PUBLISHED published: true title: Log4j 2.9 released excerpt: "

\r\nThe Apache Log4j 2 team is pleased to announce the Log4j 2.9 release!\r\n

\r\n\r\nThis release contains the first support of Java 9 as well as bugfixes and minor\r\nenhancements. The Log4j API was modified to use java.util.ServiceLoader to locate Log4j implementations,\r\nalthough the former binding mechanism is still supported. The Log4j jar is now a multi-release jar\r\nto provide implementations of the Java 9 specific classes. Multi-release jars are not supported by\r\nthe OSGi specification so OSGi modules will not be able to take advantage of these implementations\r\nbut will not lose functionality as they will fall back to the implementations used in Java 7 and 8.\r\nMore details on the new features and fixes are itemized below.\r\n

\r\n\r\nNote that subsequent to the 2.9 release, for security reasons, SerializedLayout is deprecated and no\r\nlonger used as default in the Socket and JMS appenders. SerializedLayout can still be used as before,\r\nbut has to be specified explicitly. \r\n

\r\n" id: 9872ce0a-b525-49d0-9c08-340e9327b9c5 date: '2017-08-31 01:26:00 -0400' categories: logging tags: - log4j2 - log4j - logging permalink: logging/entry/log4j-2-9-released ---

The Apache Log4j 2 team is pleased to announce the Log4j 2.9 release!

Apache Log4j is a well known framework for logging application behavior. Log4j 2 is an upgrade
to Log4j that provides significant improvements over its predecessor, Log4j 1.x, and provides
many other modern features such as support for Markers, lambda expressions for lazy logging,
property substitution using Lookups, multiple patterns on a PatternLayout and asynchronous
Loggers. Another notable Log4j 2 feature is the ability to be "garbage-free" (avoid allocating
temporary objects) while logging. In addition, Log4j 2 will not lose events while reconfiguring.

This release contains the first support of Java 9 as well as bugfixes and minor
enhancements. The Log4j API was modified to use java.util.ServiceLoader to locate Log4j implementations,
although the former binding mechanism is still supported. The Log4j jar is now a multi-release jar
to provide implementations of the Java 9 specific classes. Multi-release jars are not supported by
the OSGi specification so OSGi modules will not be able to take advantage of these implementations
but will not lose functionality as they will fall back to the implementations used in Java 7 and 8.
More details on the new features and fixes are itemized below.

Note that subsequent to the 2.9 release, for security reasons, SerializedLayout is deprecated and no
longer used as default in the Socket and JMS appenders. SerializedLayout can still be used as before,
but has to be specified explicitly. To retain old behaviour, you have to change configuration like:

into:

We do, however, discourage the use of SerializedLayout and recommend JsonLayout as a replacement:

Note that subsequent to the 2.9 release, for security reasons, Log4j does not process DTD in XML files.
If you used DTD for including snippets, you have to use XInclude or Composite Configuration instead.

The Log4j 2.9.0 API, as well as many core components, maintains binary compatibility with previous releases.

GA Release 2.9.0

Changes in this version include:

New Features

Fixed Bugs

Changes

Apache Log4j 2.9.0 requires a minimum of Java 7 to build and run. Log4j 2.3 was the last release that supported Java 6.

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 Apache Log4j 2 website:

http://logging.apache.org/log4j/2.x/