Log4j 2.5 发布，Java 日志组件
发布于 2015-12-12 00:58:34 | 290 次阅读 | 评论: 0 | 来源: 网友投递
Apache Log4j log记录软件
Log4j是Apache的一个开放源代码项目，通过使用Log4j，我们可以控制日志信息输送的目的地是控制台、文件、GUI组件，甚至是套接口服务器、NT的事件记录器、UNIX Syslog守护进程等；我们也可以控制每一条日志的输出格式；通过定义每一条日志信息的级别，我们能够更加细致地控制日志的生成过程。最令人感兴趣的就是，这些可以通过一个配置文件来灵活地进行配置，而不需要修改应用的代码。
Log4j 2.5 发布，此版本是第九个 GA 版本，包括一些 bug 修复和新特性。新特性包括在 file rollover 的时候指定删除操作；一个基于 CRON 的触发策略；过滤器支持 JSR 223 脚本，模式选择器和删除操作，新增一个策略移除 RoutingAppender 的闲置输出源。
Log4j 2 最低要求 Java 7。
Log4j 2.5 改进列表：
新特性：
o LOG4J2-435: Added support for custom delete actions triggered by a rollover. Thanks to
Robert Schaft.
o LOG4J2-89: Allow rollover to occur at any time. Add CronTriggeringPolicy.
o LOG4J2-1136: Add support for JSR 223 scripts in filters and the PatternSelector.
o LOG4J2-1168: Add getters for source and destination file in file rename action. Thanks
to Steven Swor.
o LOG4J2-1175: Add getters for classes in org.apache.logging.log4j.core.appender.rolling.action.
o LOG4J2-898: Added system property to allow users to control whether messages should be
formatted in the background.
o LOG4J2-1178: Support use-case for JDBC's CommonDataSource.setLogWriter(PrintWriter) and
java.sql.DriverManager.setLogWriter(PrintWriter).
o LOG4J2-1187: Support use case for java.sql.DriverManager.setLogStream(PrintStream).
Bugs 修复：
o LOG4J2-324: Reduced memory usage of status messages in bounded queue; support zero-length
queue that stores no messages.
o LOG4J2-1173: Fixed rollover error when copying to a directory mapped to a remote Linux
host.
o LOG4J2-1195: Make KafkaAppender support SerializedLayout. Thanks to Melvin Du.
o LOG4J2-381: Allow triggering policy and rollover strategy to be modified during reconfiguration.
Thanks to Anthony Baldocchi.
o LOG4J2-1029: Performance improvement when gathering location information. Thanks to Stefan
Leonhartsberger.
o LOG4J2-1172: Fixed ThreadLocal leak [AsyncLogger$Info] on Tomcat when using AsyncLoggerContextSelector.
o LOG4J2-1176: Fixed memory leak when log4j jars are in Tomcat's lib folder.
o LOG4J2-1180: Logger cache does not account for message factory. Thanks to Mikael Ståldal.
o LOG4J2-879: Documentation: fixed minor issues with the site and manual pages.
o LOG4J2-999: RollingFileAppender should also roll over when log event time is equal to rollover
time, not only when later. Thanks to Joan Balagueró.
o LOG4J2-873: Fixed bug where omitting the <display-name> element in web.xml caused
incorrect log4j initialization,
resulting in memory leaks when the web application was stopped or reloaded. Thanks
to Martin Dickins, LC, Luke Woodward.
o LOG4J2-323: Better web app support for async loggers: Fixed a memory leak that occurred
when the logging jars are placed
in the container's classpath and the configuration file uses AsyncRoot/AsyncLogger.
The problem was that the first web application started the Disruptor background thread
[AsyncLoggerConfig-1] but did not stop it until all web apps are stopped.
Each web application now has its own Disruptor which is stopped/started together with
the web app.
o LOG4J2-493: Better web app support for async loggers: it is now possible to place the logging
jars in the container's
classpath when making all loggers asynchronous by using AsyncLoggerContextSelector.
This fixes a problem where
logging would stop working after stopping and restarting a web application.
o LOG4J2-1171: Use servlet context name for logger context name when available.
o LOG4J2-1159: Fixed a ThreadLocal memory leak in Tomcat8 that mentions AsyncLoggers when
Async Loggers are not used.
o LOG4J2-1166: AbstractConfiguration executor should use a DaemonThreadFactory.
o LOG4J2-1165: Improve Log4j initialization status messages.
o LOG4J2-1156: Web site corrections and updates.
o LOG4J2-1158: Log4J JUL adapter is using MessageFormat on String passed by java.util.function.Supplier<String>.
Thanks to Michael Fortin, Gary Gregory.
o LOG4J2-801: org.apache.logging.log4j.core.Logger should be serializable.
o LOG4J2-1157: Fix compilation error for classes annotated with @Plugin. Thanks to Norbert
Bartels.
o LOG4J2-948: Fix plugin documentation error about Converters. Thanks to Andrew Flower.
o LOG4J2-1193: Prefix all thread names Log4j creates with "Log4j2-".
o LOG4J2-1194: Documentation does not match parameters for LoggerNameLevelRewritePolicy.
Thanks to Adam Brin.
o LOG4J2-1196: MongoDbConnection does not close MongoClient. Thanks to René Zanner.
改进：
o LOG4J2-649: Add PurgePolicy and IdlePurgePolicy to RoutingAppender. Thanks to Aleksey Zvolinsky.
o LOG4J2-1202: Remove ConfigurationMonitor. The WatchManager is now used to check for configuration
changes.
o LOG4J2-1174: Update Jackson from 2.6.2 to 2.6.3.
o LOG4J2-1207: Update kafka-clients from 0.8.2.2 to 0.9.0.0.
Log4j 是Apache的一个开放源代码项目，通过使用Log4j，我们可以控制日志信息输送的目的地是控制台、文件、GUI组件、甚至是套接口服务 器、NT的事件记录器、UNIX Syslog守护进程等;我们也可以控制每一条日志的输出格式;通过定义每一条日志信息的级别，我们能够更加细致地控制日志的生成过程。最令人感兴趣的就 是，这些可以通过一个配置文件来灵活地进行配置，而不需要修改应用的代码。
历史版本 :
Apache Log4j 2.10.0 正式发布，包含大量更新
Apache Log4j 2.9.1 发布，Java 日志组件
LOG4J 2.9.0 发布，Java 日志组件
Apache Log4j 2.8.2 发布，Java 日志组件
Log4j 2.8.2 发布，Java 日志组件
Log4j 2.8.1 发布，Java 日志组件
Log4j 2.8 发布，Java 日志组件
LOG4J 2.7 发布，Java 日志组件
Apache Log4j 2.6.2 发布，Java 日志组件
Log4j 2.6 发布，Java 日志组件
Log4j 2.5 发布，Java 日志组件
Apache Log4j 2.4.1 发布，Java 日志组件