The Apache Log4j 2 team is pleased to announce the Log4j 3.0.0-alpha1 release!
The artifacts may be downloaded from
https://logging.apache.org/log4j/3.x/download.html.
As the Java ecosystem has evolved, requests have been received from users, and
the need for improved security has become more apparent, changes were
necessariy in Log4j’s design:
• With the introduction of the Java Platform Module System (JPMS) changes
were needed to how the various log4j modules are packaged. While not every
log4j module is now a fully compliant JPMS module with its own module-info.java
file, all the modules likely to be used in a JPMS environment are.
• Many optional components, such as Scripting, JNDI, JPA and JMS, have been
moved to their own modules. This makes Log4j-core slightly smaller in 3.x and
aids in security by not having jars with unwanted behaviors present, making
disabling them via system properties unnecessary.
• All plugins constructed using Log4j 3.x are now located using Java’s
ServiceLoader. This avoids many of the problems users had packaging plugins in
"shaded" jars as that technology directly supports ServiceLoader. Plugins
constructed using Log4j 2.x will still function in Log4j 3.x.
• Log4j’s annotation processor has been individually packaged separate from
Log4j-core and the plugin system it enables. For applications using the module
path this makes it easier to provide the annotation processor since it must be
explicitly declared in those cases.
• Log4j 3.x now uses an internal dependency injection framework to allow
plugins to be injected with instances of classes they are dependent on.
• Many system properties used by Log4j can now be set to apply to a single
LoggerContext making configuration in application frameworks that support
multiple applications more flexible.
• Some deprecated classes have been removed. However, every attempt has
been made to ensure that user code compiled for Log4j 2.x will continue to
operate with the Log4j 3.x libraries present instead.
Apache Log4j 3.0.0-alpha1 requires a minimum of Java 11 to build and run.
For complete information on Apache Log4j 3.x, including instructions on how to
submit bug reports, patches, or suggestions for improvement, see the Apache
Log4j 3.x website - https://logging.apache.org/log4j/3.x/.
Changes
Added
• Allow plugins to be created through more flexible dependency injection
patterns. (for LOG4J2-1188 by Matt Sicker)
• Allow to force LOG4J2 to use TCCL only. (for LOG4J2-2171 by rmannibucau,
Ralph Goers)
• Allow web lookup to access more information. (for LOG4J2-2523 by Romain
Manni-Bucau, Ralph Goers)
• Allow web lookup of session attributes. (for LOG4J2-2688 by Ralph Goers,
Romain Manni-Bucau)
• Add support for injecting plugin configuration via builder methods. (for
LOG4J2-2700 by Matt Sicker)
• Add scopes API for customizing plugin instance lifecycle. (for
LOG4J2-2852 by Matt Sicker)
• Add qualifier annotations for distinguishing instances of the same type.
(for LOG4J2-2853 by Matt Sicker)
• Create standardized dependency injection API. This is supported in
several plugin categories and other configurable instances previously defined
via system properties. (for LOG4J2-2854 by Matt Sicker)
• Add conditional annotations to support more declarative binding factory
bundle classes. (for LOG4J2-3300 by Matt Sicker)
• Add built-in JSON configuration parser for a useful structured
configuration file format which only requires the java.base module. (for
LOG4J2-3415 by Matt Sicker)
• Add @Ordered annotation to support plugin ordering when two or more
plugins within the same category have the same case-insensitive name. (for
LOG4J2-857 by Matt Sicker)
Changed
• Simplify Maven site phase and align it with the one in 2.x branch. (for
1220 by Volkan Yazıcı)
• Update build to use Java 11 bytecode. (for 480 by Ralph Goers)
• Convert documentation into AsciiDoc format. (for LOG4J2-1802 by Matt
Sicker)
• Rename package core.util.datetime to core.time.internal.format to clarify
these classes are to be considered private. (for LOG4J2-2224 by Remko Popma)
• Move time-related classes from core.util to core.time. Classes considered
private moved to core.time.internal. (for LOG4J2-2225 by Remko Popma)
• Split off Kafka support into a new module log4j-kafka. (for LOG4J2-2227
by Gary Gregory)
• Split off ZeroMq/JeroMq support into a new module log4j-jeromq. (for
LOG4J2-2228 by Gary Gregory)
• Split off SMTP support into a new module log4j-smtp. (for LOG4J2-2230 by
Gary Gregory)
• Split off CSV layout into a new module log4j-csv. (for LOG4J2-2231 by
Gary Gregory)
• Split off JMS support into a new module log4j-jms. (for LOG4J2-2232 by
Gary Gregory)
• Split off JDBC support into a new module log4j-jdbc. (for LOG4J2-2233 by
Gary Gregory)
• Split off Jackson-based layouts into their own module