The Apache Log4j 2 team is pleased to announce the Log4j 2.9.0 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:

  <Socket name="socket" host="localhost" port="9500"/>


  <Socket name="socket" host="localhost" port="9500">

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

  <Socket name="socket" host="localhost" port="9500">
    <JsonLayout properties="true"/>

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

        • LOG4J2-2008: Support printing multiple StructuredData elements in 
        • LOG4J2-1986: Public API for parsing the output from 
JsonLayout/XmlLayout/YamlLayout into a LogEvent.
        • LOG4J2-1981: JsonLayout, XmlLayout and YamlLayout support 0-byte 
termination of log events.
        • LOG4J2-1864: Support capped collections for MongoDb appender. Thanks 
to Matthias Kappeller.
        • LOG4J2-1813: Log4j2 will now print all internal logging to the 
console if system property log4j2.debug is defined with any value (or no value).
        • LOG4J2-1766: Temporary compress directory during rollover (#88). 
Thanks to Pierrick HYMBERT.
        • LOG4J2-1814: Added wrapper classes CustomLoggerGenerator and 
ExtendedLoggerGenerator to avoid class name with a dollar ($) character which 
has special meaning in many *nix command line environments.
        • LOG4J2-1884: Added process ID (pid) pattern converter.
        • LOG4J2-1699: Configurable Log File Permissions with 
PosixFilePermission. Thanks to Demetrios Dimatos, Pierrick HYMBERT.
        • LOG4J2-1945: Generate source jas for all test jars.
        • LOG4J2-1934: JMS Appender does not know how to recover from a broken 
        • LOG4J2-1955: JMS Appender should be able connect to a broker (later) 
even it is not present at configuration time.
        • LOG4J2-1874: Added methods ::writeBytes(ByteBuffer) and 
::writeBytes(byte[], int, int) to ByteBufferDestination interface and use these 
methods in TextEncoderHelper where possible to prepare for future enhancements 
to reduce lock contention. Thanks to Roman Leventov.
        • LOG4J2-1442: Generic HTTP appender.
        • LOG4J2-1935: Add with(String, primitive) methods to 
        • LOG4J2-1930: Add forEach() methods to 
        • LOG4J2-1932: Add containsKey() methods to 
        • LOG4J2-1854: Support null byte delimiter in GelfLayout. Thanks to 
Xavier Jodoin.
        • LOG4J2-1359: Add support for Java 9 StackWalker.
        • LOG4J2-1880: Warn when a configuration file for an inactive 
ConfigurationFactory is found.
        • LOG4J2-1855: Add an optional random delay in 
TimeBasedTriggeringPolicy Thanks to Anthony Maire.
        • LOG4J2-1860: Shortcut to add Property and KeyValuePair component in 
        • LOG4J2-1294: The JMS Appender should use a JMS MapMessage for a Log4j 
Fixed Bugs

        • LOG4J2-1833: Prevent NullPointerException when a file name is 
specified with the DirectWriteRolloverStrategy.
        • LOG4J2-2018: Fix incorrect documentation for 
        • LOG4J2-922: Parameter of mdcId in SyslogAppender has no default 
value. Thanks to angus.aqlu, Paul Burrowes.
        • LOG4J2-2001: StyleConverter.newInstance argument validation is 
incorrect. Thanks to Paul Burrowes.
        • LOG4J2-1999: HighlightConverter converts all unrecognized levels to 
DEBUG. Thanks to Paul Burrowes.
        • LOG4J2-2013: SslSocketManager does not apply SSLContext on TCP 
reconnect. Thanks to Taylor Patton, Gary Gregory.
        • LOG4J2-2016: Mark FileRenameAction as successful when using 
alternative ways to move files. Thanks to Benjamin Jaton.
        • LOG4J2-2012: No compression when using a separate drive in Linux. 
Thanks to Benjamin Jaton.
        • LOG4J2-1888: Log4j throws a 
java.nio.charset.UnsupportedCharsetException: cp65001. Thanks to Misagh Moayyed.
        • LOG4J2-1990: ConcurrentModificationException logging a parameter of 
type Map. Thanks to Philippe Mouawad.
        • LOG4J2-1311: SocketAppender will lose several events after 
re-connection to server. Thanks to Xibing Liang.
        • LOG4J2-1977: Consider the StringBuilder's capacity instead of content 
length when trimming. Thanks to Jerry xnslong.
        • LOG4J2-1971: Register log4j-core as an OSGi service. Skip tests for 
LOG4J2-1766 on MacOS. Use group "staff" for LOG4J2-1699 test on MacOS.
        • LOG4J2-1994: TcpSocketServer does not close accepted Sockets.
        • LOG4J2-1987: Log4J JUL Bridge and RMI Security Manager causes access 
denied ("java.util.logging.LoggingPermission" "control") Thanks to Andreas 
        • LOG4J2-1982: Log4j-config.xsd only allows one AppenderRef element for 
each Logger element. Thanks to Christoph Lembeck.
        • LOG4J2-1985: Fix default buffer size to match documentation (from 
8102 to 8192 a.k.a. 8KB.) Thanks to Kenneth McFarland.
        • LOG4J2-1912: CompositeConfiguration logs warning "Unable to determine 
URI for configuration." However, the reconfiguration is completed. Thanks to R 
        • LOG4J2-1964: Dynamic reconfiguration does not work for filePattern of 
RollingFile. Thanks to Pierrick HYMBERT.
        • LOG4J2-1961: Reconfigure breaks DirectWriteRolloverStrategy. Thanks 
to Christian Vent.
        • LOG4J2-1943: The eventPrefix attribute was being ignored in the 
        • LOG4J2-1953: JndiManager is not released when the JmsAppender builder 
catches an exception trying to build itself.
        • LOG4J2-1911: Improve the documentation of the DynamicThresholdFilter.
        • LOG4J2-1929: EOFException with FormattedMessage. Thanks to Borys 
        • LOG4J2-1948: Trim levels read from properties file to remove trailing 
spaces. Thanks to Michael Lück.
        • LOG4J2-1971: ClassCastException: 
org.eclipse.osgi.internal.loader.SystemBundleLoader$1 cannot be cast to 
java.lang.ClassLoader. Thanks to liwenxian2017.
        • LOG4J2-1876: More reliable checking for runtime dependencies.
        • LOG4J2-1867: Fix configuration documentation.
        • LOG4J2-1858: Ensure the ThreadLocal StringBuilder in 
ParameterizedMessage won't hold excessively much memory after logging a long 
        • LOG4J2-1885: Fix documentation about default additivity value for 
        • LOG4J2-1920: ScriptEngineManager is not available in Android and 
causes a NoClassDefFoundError. Thanks to Ajitha.
        • LOG4J2-1989: Clarify Javadoc for AbstractTriggeringPolicy. Thanks to 
Kenneth McFarland.
        • LOG4J2-1993: Fix compiler warnings in LoggerConfigTest. Thanks to 
Kenneth McFarland.

        • LOG4J2-1928: Add support for DirectWriteRolloverStrategy to 
        • LOG4J2-2022: RFC5424Layout now prints the process id.
        • LOG4J2-2020: Remove default layout from KafkaAppender.
        • LOG4J2-2023: Use a class' canonical name instead of name to create 
its logger name.
        • LOG4J2-2015: Allow KeyStoreConfiguration and TrustStoreConfiguration 
to find files as resources.
        • LOG4J2-2011: Replace JCommander command line parser with picocli to 
let users run Log4j2 utility applications without requiring an external 
        • LOG4J2-1984: Allow maxLength of StructuredData to be specified by the 
        • LOG4J2-1071: Allow for bufferSize=0 in SMTP appender. Thanks to Ben 
Ludkiewicz, Benjamin Jaton.
        • LOG4J2-1261: Async Loggers no longer use deprecated LMAX Disruptor 
APIs. (Disruptor-3.3.3 or higher is now required.)
        • LOG4J2-1908: Improved error message when misconfigured with multiple 
incompatible appenders targeting same file.
        • LOG4J2-1954: Configurations with multiple root loggers now fail 
        • LOG4J2-1958: Deprecate SerializedLayout and remove it as default.
        • LOG4J2-1959: Disable DTD processing in XML configuration files.
        • LOG4J2-1950: Fix docker build with jdk9 requirements (#84). Thanks to 
Pierrick HYMBERT.
        • LOG4J2-1801: Add more detail to WARN "Ignoring log event" messages 
printed to the console after log4j was shut down.
        • LOG4J2-1926: Facilitate log4j use in Android applications: remove 
dependency on RMI and Management APIs from log4j-api.
        • LOG4J2-1956: JMS Appender broker password should be a char[], not a 
        • LOG4J2-1917: Support using java.util.ServiceLoader to locate Log4j 2 
API providers.
        • LOG4J2-1966: Include separator option of PatternLayout in manual (and 
other updates). Thanks to M Sazzadul Hoque.
        • LOG4J2-1851: Move server components from log4j-core to new 
log4-server module.
        • LOG4J2-1991: Refactor SimpleMessage to be concise and clear (#100) 
Thanks to .
        • LOG4J2-2017: Update Jackson from 2.8.9 to 2.9.0.
        • LOG4J2-1868: Update ZeroMQ's JeroMQ from 0.3.6 to 0.4.0.
        • LOG4J2-1960: Update ZeroMQ's JeroMQ from 0.4.0 to 0.4.1.
        • LOG4J2-1974: Update ZeroMQ's JeroMQ from 0.4.1 to 0.4.2.
        • LOG4J2-1869: Update Kafka client from to
        • LOG4J2-1962: Update Kafka client from to
        • LOG4J2-1872: Update JavaMail from 1.5.5 to 1.5.6.
        • LOG4J2-1879: Update JAnsi from 1.14 to 1.15.
        • LOG4J2-1877: Missing documentation for Max index limit in 
DefaultRolloverStrategy. Thanks to Chandra Tungathurthi.
        • LOG4J2-1899: Add missing getters to classes in package
        • LOG4J2-1900: Update JAnsi from 1.15 to 1.16.
        • LOG4J2-: Update SLF4J from 1.7.24 to 1.7.25.
        • LOG4J2-1938: Update Jackson from 2.8.7 to 2.8.9.
        • LOG4J2-1970: Update HdrHistogram from 2.1.8 to 2.1.9.
        • LOG4J2-1975: Update javax.persistence from 2.1.0 to 2.1.1.
        • LOG4J2-1976: Update org.osgi.core from 4.3.1 to 6.0.0.
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:

Reply via email to