## Logback News

You can receive logback-related announcements by subscribing to the QOS.ch announce mailing list.

### March Xth, 2016, Release of version 1.1.7

Unneccessary and incompatible %i token in fileNamePattern option with `RolliRollingFileAppender/TimeBasedRollingPolicy` is now detected and the user alerted to the misconfiguration problem. This fixes LOGBACK-1143.

### February 29th, 2016, Release of version 1.1.6

`LogbackValve` (in logback-access) now attempts to load the configuration file as a resource if it cannot be found on the filesystem (LOGBACK-1069). This is helpful in scenarios where applications are using an embedded Tomcat server.

`JMXConfigurator.reloadDefaultConfiguration()` method now tolerates programmatic configuration without a URL. This change was provided by Vedran Pavic in PR 302.

`RollingFileAppender` will output an error message if the date time pattern in the %d token within the fileNamePattern is not collision free. This fixes LOGBACK-1137. In a similar vein, every instance of `FileAppender` will now detect if it shares the same File option value as given for an appender defined earlier. In addition, `RollingFileAppender` instances now check for colliding FileNamePattern values.

Fixed `NullPointerException` thrown by `RollingFileAppender` if the name of the rollover target path did not contain a parent. This issue was reported in LOGBACK-1054 by Paulius Matulionis. Analysis of the problem and the relevant PR was provided by Ferenc Palkovics.

`BasicConfigurator.configure` method call executes significatly faster. Improved documentation for configuration using JDK 1.6 service-provider facility. These changes are in response to LOGBACK-1141 requesting faster logback start-up time.

Fixed issue with variable substitution with the value ending in a colon. This problem was reported in LOGBACK-1140 by Eric Cook.

### February 13th, 2016, Release of version 1.1.5

#### MDC values are no longer inherited by child threads.

Child threads no longer inherit MDC values. In previous versions of logback as well as log4j 1.x, MDC values were inherited by child threads. Several users have argued convincingly that MDC inheritance by child threads was unhelpful and even dangerous. This change fixes LOGBACK-422 and LOGBACK-624

When the `FileNamePattern` string for `RollingFileAppender/SizeAndTimeBasedFNATP` lacks a %i token, then compression for the second archive in the same period cannot occur as the target file already exists. Under those circumstances, logback leaves behind .tmp files as reported in LOGBACK-992, LOGBACK-173 and LOGBACK-920. In this release, this particular condition is detected by `RollingFileAppender` which will not start but alert the user instead.

AsyncAppender is now configurable to never block. This feature was requested by Jeff Wartes in LOGBACK-898 with Jeff Wartes and Gareth Davis providing the relevant patch.

### February 11th, 2016, Release of version 1.1.4

#### Logback 1.1.4 requires SLF4J version 1.7.16 or later.

Added event replay support as introduced in SLF4J version 1.7.15. In most circumstances, logack-classic should run fine with earlier versions of slf4j-api, including all versions in the 1.6.x and 1.7.x series. However, with a version of slf4j-api.jar earlier than 1.7.15 in the classpath, attempting introspection of a `Logger` instance will result in a `NoClassDefFoundError` similar to that shown below.

    Exception in thread "main" java.lang.NoClassDefFoundError: org/slf4j/event/LoggingEvent
            at java.lang.Class.getDeclaredMethods0(Native Method)
            at java.lang.Class.privateGetDeclaredMethods(Class.java:2451)
            at java.lang.Class.privateGetPublicMethods(Class.java:2571)
            at java.lang.Class.getMethods(Class.java:1429)
            at java.beans.Introspector.getPublicDeclaredMethods(Introspector.java:1261)
            at java.beans.Introspector.getTargetMethodInfo(Introspector.java:1122)
            at java.beans.Introspector.getBeanInfo(Introspector.java:414)
            at java.beans.Introspector.getBeanInfo(Introspector.java:161)

#### Packaging data (as output in stack traces) is now disabled by default.

In case an application throws exceptions frequently, then computing packaging data can be very costly and will cause the application to run slower. Making bad worse. To alleviate this problem, packaging data is no longer computed by default. It has to be enabled explicitly. In the absence of explicit instructions, i.e the user has not specified a converter handling exceptions, `PatternLayout` in logback-classic will follow the settings defining for the logging environment. If packaging data is disabled, then it add %ex as a suffix in the pattern, and if packaging data is enabled then %xEx will be added. These changes fix LOGBACK-730 and LOGBACK-966.

Fixed a bug in `TimeBasedFileNamingAndTriggeringPolicyBase` causing time-based rolling policies to always rollover according to the local system time and ignore the time zone passed in the file name pattern. The issue was reported by Lukasz Sanek who also provided the the relevant fix.

`AsyncAppenderBase` now restores the current thread's interrupt flag when catching an `InterruptedException`. The issue (LOGBACK-910) was raised by Henrik Nordvik who also provided the relevant fix.

### 24th of March 2015, Release of version 1.1.3

#### As of version 1.1.3, all logback modules require JDK 1.6 instead of previously JDK 1.5. This change was put to consultation on the logback mailing lists with no objections raised.

Fixed `FileAppender`'s prudent mode so that it properly recovers from IO Errors (LOGBACK-1046)

Irrelevant or internal stack trace lines can now be omitted. Pull request provided by Tomasz Nurkiewicz (LOGBACK-540).

`AccessEvent` now creates a copy of request attributes when its `prepareForDeferredProcessing()` method is called. This makes attributes visible even if an appender uses a background thread to process events. (LOGBACK-1033)

All threads opened by `ch.qos.logback.core.util.ExecutorServiceUtil#THREAD_FACTORY` are now daemons, which fixes an application hang on shutdown when `LoggerContext#stop()` is not called (LOGBACK-929). Note that daemon threads are abruptly terminated by the JVM, which may cause undesirable results, such as corrupted files written by the `FileAppender`. It is still highly recommended for the application to call `LoggerContext#stop()` (e.g., in a shutdown hook) to gracefully shutdown appenders.

Fixed an issue with `RollingFileAppender` where the first rollover file could be unintentionally deleted, depending on the specified filename pattern (LOGBACK-894).

Fixed an issue with `TeeHttpServletResponse` where the system default encoding would be used instead of the response encoding when constructing a new writer (LOGBACK-1023).

Fixed `ConfigurationDelegate.groovy` to allow any appender that implements `AppenderAttachable`, which supports third-party appenders, such as reactor-logback's `AsyncAppender` (LOGBACK-1008)

Added support for specifying the callstack depth range in the `PatternLayout`. For example, `%caller{1..2}` displays the first two calls in the callstack.

Added HTTP request method to `MDCInsertingServletFilter`.

Fixed time-zone dependent code in `RollingCalendarTest`. (LOGBACK-116)

Simplified connection logic of SocketApender to reduce multi-threading overhead and unnecessary instantiation of `SocketConnector` objects.

Fixed race condition in `SMTPAppenderBase` causing missing or duplicate emails. (LOGBACK-909)

Fixed an issue with `FileAppender` in prudent mode, where an interrupt could prevent further access to the file (LOGBACK-875).

Fixed `IllegalStateException` when multiple threads write files to same directory (LOGBACK-128).

Changed queue consumption strategy in `AbstractSocketAppender` from "take" to "peek/remove" in order to avoid losing an event on each socket connection break. Zero is now a deprecated queue size. A queue size of one should be taken instead to indicate synchronous processing. (LOGBACK-977)

`RequestLogImpl` now has an overridable `configure` method to allow extending implementations to configure it via methods other than the `logback-access.xml` file.

Fixed a bug in `AccessEvent` which could cause any `AsyncAppender` based appender to corrupt the request headers, request parameters, or response headers, before logging.

SQL scripts to setup your logback database are now provided as JAR resources (LOGBACK-948).

Threads created internally by logback are now named logback-n, where n is an integer. For the first thread n is set to 1, for each successive thread n is incremented by 1.

Added max runtime parameter to `AsyncAppender` to allow the appender to flush events, up to a maximum delay, during a stop of the LoggerContext. This can be used to ensure that all queued events are flushed.

Added new configuration element `shutdownHook` to allow the user to specify a ShutdownHook implementation that will stop the Logback context upon JVM exit.

`BasicStatusManager` now prevents adding more than one instance of `OnConsoleStatusListener` as a status listener. This fixes LOGBACK-976.

`TimeBasedRollingPolicy` now accepts a time zone in its `%d` conversion pattern. (LOGBACK-611)

It is now possible to configure the character encoding used by `SyslogAppender` to encode messages using the `setCharset()` method. This fixes LOGBACK-732

### 2nd of April, 2014 - Release of version 1.1.2

Create an abstract method, createOutputStream, as an extension point for subclasses of SyslogBaseAppender to create their own OutputStream. LOGBACK-890

Removed deprecated constructors in `SocketAppender` and related classes.

Fixed incorrect date format in `SyslogAppender`. (LOGBACK-936)

Fixed `NullPointerException` when substituting blank variables (LOGBACK-959)

Fixed `NullPointerException` that occurs when stopping a `SyslogAppender` that did not properly initialize, e.g., due to a hostname resolution failure. (LOGBACK-960)

Use fair locking in `OutputStreamAppender`. Patch provided by Sergey Bykov. (LOGBACK-268)

In case of missing included files, IncludeAction no longer prints a stack trace but prints a warning instead. (LOGBACK-954)

Fixed character escaping in XMLLayout (LOGBACK-728) and HTMLLayout (LOGBACK-440).

### 5th of February, 2014 - Release of version 1.1.1

Logback now supports an unlimited level of variable resolution graphs rather than being limited to one level deep resolution. This enhancement was requested by Anton Wiedermann in LOGBACK-943 with Eric Dahl providing the relevant pull request.

Fixed LOGBACK-942 which was causing `SocketAppender` to drop events. Eric Dahl provided the relevant pull request.

### January 28th, 2014 - Release of version 1.1.0

Previously, logback silently ignored configuration files that did not have the ".xml" or ".groovy" file extension. Now, a `LogbackException` is thrown to flag this error.

Groovy configuration now supports `appenderRef`, which allows the use of `AsyncAppender` in Groovy. (LOGBACK-269)

`SizeAndTimeBasedFNATP` now supports a protected function `#createArchiveRemover` that allows subclasses to specify a custom archive remover used in `RollingFileAppender`. The default archive remover is `SizeAndTimeBasedArchiveRemover`.

`PackagingDataCalculator` now catches and ignores `UnsupportedOperationException` so that it can determine whether the JVM supports `Reflection#getCallerClass()` without printing that exception's stack trace. This only affects Java 7u40+, which removed support for `Reflection#getCallerClass()`. (LOGBACK-885)

To facilitate debugging, `SimpleSocketServer` now names its threads: "Logback SimpleSocketServer (port PORTNUM)". `SocketNode` client threads are named: "Logback SocketNode (client: IPADDR)".

Fixed silently lost messages from `SyslogAppender` when they exceeded the system datagram size limit. The default max message size was hard coded to 65KB but now matches the system limit (as read from `DatagramSocket#getSendBufferSize()`) unless a nonzero limit is specified via `SyslogAppender#setMaxMessageSize()`. (LOGBACK-926)

Fixed various documentation typos, including LOGBACK-466, LOGBACK-768, LOGBACK-904, LOGBACK-921, and LOGBACK-927.

`ContextBase.setStatusManager` now correctly validates the given status manager. (LOGBACK-912)

The `SocketNode` creates an `ObjectInputStream` using the socket's input stream, which blocks waiting for the stream header. This wait has been moved from the constructor to `SocketNode.run()` so that the node can be created without blocking. (LOGBACK-350)

Fixed `SecurityException` during initialization in Google AppEngine. (LOGBACK-760)

The `<include>` element now allows optional resources (previously, only optional files). (LOGBACK-928)

Added new layout conversion word (%D or %elapsedTime), which gets the time taken to serve the request. This applies only to Jetty and Tomcat logs via logback-access. (LOGBACK-320)

Fixed SMTP error when the subject line contained multiple new-lines. (LOGBACK-865)

Fixed unnecessary re-initialization of the servlet's `LoggerContext` while attempting to destroy it.

Added the following syslog facilities to `SyslogStartConverter`: NTP, AUDIT, ALERT, CLOCK (LOGBACK-754)

Fixed `NullPointerException` when setting a JUL logger's level to null, which should have reset the logger level to the parent's effective level. (LOGBACK-906)

Added support to get suppressed exceptions. This is currently only implemented for `RootCauseFirstThrowableProxyConverter` and `ThrowableProxyConverter`. (LOGBACK-516)

Fixed problem of Janino classes not found in some environments (axis2, GWT, etc.). (LOGBACK-832)

Fixed various unit tests, including modifications for consistent results in Jenkins. (LOGBACK-842)

Allow Gaffer to read the `logback.debug` system property to enable verbose output during Groovy-based configuration. Also added debug statements to Gaffer.

Fixed `IllegalArgumentException` when missing periods and dollar signs in the logger name. (LOGBACK-384)

Fixed `NullPointerException` during JNDI lookup.

Fixed dangling data source connections from `DBAppender` that caused "maximum open cursors exceeded".

Fixed incorrect stack trace depth when specifying `%throwable` with argument. (LOGBACK-160)

Fixed MySQL setup script to use lower-case table name to match the references in the file. This had caused an error on systems where case sensitivity matters.

Fixed `NullPointerException` when getting code source in `PackagingDataCalculator`.

The search path for `logback-access.xml` is now `${catalina.base}` and then `${catalina.home}` if not found. (LOGBACK-844)

The `LoggingEvent` constructor delays message formatting so that it can be computed lazily by the `getFormattedMessage` method. This fixes LOGBACK-873 and re-fixes LOGBACK-495.

`PackagingDataCalculator` now checks for the case where the caller has no protection domain. This fixes LOGBACK-617 reported by Yuri de Wit. The relevant fix was provided by Mikhail Mazursky.

### May 10th, 2013 - Release of version 1.0.13

In logback-access MANIFEST file, imports of Jetty and Tomcat are now optional. This fixes LOGBACK-300 reported by Christian Brensing who also provided the appropriate pull request.

Logback will now correctly parses variables with a default separator string nested within accolades, e.g. "{a:-b}". Such strings resemble variable references but lack the $ prefix, e.g "${a:-b}". This fixes LOGBACK-859 reported by Yoni Moses.

In `InterpretationContext` class replaced code using JDK 1.6 API with code using JDK 1.5. This fixes LOGBACK-860 reported by Bas Stoker.

Updated the "org.fusesource.jansi:jansi" dependency to version 1.9.

### April 26th, 2013 - Release of version 1.0.12

A new `SSLSocketAppender` extends the basic `SocketAppender` providing the ability to deliver logging events over the Secure Socket Layer (SSL). The corresponding `SimpleSSLSocketServer` extends the classic `SimpleSocketServer` as a basic logging server application that receives logging events from a `SSLSocketAppender`.

Receiver components are configured in logback.xml just like any other logback component.

While `SimpleSocketServer` (and its new SSL-enabled counterpart, `SimpleSSLSocketServer`) provide an easy-to-use standalone logging server application, a new component type known as a receiver allows any application to receive logging events from remote appenders over a TCP/IP network connection, using Logback Classic. Receiver components are configured in logback.xml just like any other logback component.

A receiver can either listen passively for connections from remote `SocketAppender` components acting as clients, or it can assume the client role, initiating a connection to a remote appender acting as a server. The receiver components shipped with Logback include full support for logging event delivery over the Secure Sockets Layer (SSL).

All of the new socket-based receiver and appender components were contributed by Carl Harris. See Receivers in the Logback Manual for more information on configuring receiver components. See SocketAppender and ServerSocketAppender for information on configuring appenders as event sources for receiver components.

`RollingFileAppender` will now detect when file property collides with fileNamePattern, emit an error message and refuse to initialize. This was requested in LOGBACK-796 by Karl Pietrzak who also provided a patch.

In configuration files, the `<include>` element now admits the optional attribute. This fixes LOGBACK-230 reported by Attila Kiraly. Many thanks to Tommy Becker who contributed a patch.

In response to LOGBACK-829, serialization of `Logger` instances has been significantly simplified and much unnecessary bloat removed. As an added bonus, the new serialization of `Logger` objects is also compatible with serialization streams using older Logger instances. `Logger` instances serialized by logback 1.0.11 and earlier can be read by logback version 1.0.12 and later and vice-versa.

The code detecting whether Groovy is available on the class path deals with the case where logback binaries are installed as endorsed libraries. This fixes LOGBACK-831.

Groovy configurator no longer supports `SiftingAppender`.

In response to LOGBACK-244, LOGBACK-724 and in particular patches provided by Tommy Becker and David Roussel component tracking code has been simplified and completely re-written. `SiftingAppender` now supports the timeout and maxAppenderCount parameters. As a direct consequence of modifications to component tracking code, the groovy configurator no longer supports `SiftingAppender`.

SiftingAppender now propagates properties defined elsewhere in the configuration file into the configuration process of nested appenders. This fixes LOGBACK-833 with David Roussel providing the appropriate patch.

As all other actions affecting properties, `TimestampAction` now inserts the user-specified property into the local scope by default. The property was inserted into the context scope in earlier versions of logback. This fixes LOGBACK-835 with David Roussel providing the appropriate patch.

Logback is now able to retrieve the name of localhost when running under OS X and Java 7. This issue was reported by LOGBACK-749 by Oliver Schrenk with patches provided by Ralph Goers and Pavel Valodzka.

The mdc converter can now handle default values. This feature was requested in LOGBACK-246 by Michael Osipov with Denis Bazhenov providing a patch.

`DBAppender` in logback-classic module no longer assumes that caller information is always available. This fixes LOGBACK-805 reported by Daris Cooper who also provided a corrective patch.

In order to simplify our build, several unit tests have been ported from Scala to Java. It follows that logback no longer depends on Scala, not even during the test phase of the build.

### 25th of March, 2013 - Release of version 1.0.11

Under Unix*, the basic/quick file rename method supplied by Java does not work if the source and target files are on different file systems. This problem was reported in LOGBACK-108 by Daniel Potter. In order to deal with this issue, logback now will perform rename by copying if the source and target files are on different file systems and the host JDK is version 1.7 or later. See also the related error code.

The "cn" conversion word now correctly maps to `ContextNameConverter` class. This fixes LOGBACK-463 reported by Michael Osipov with Mark A. Ziesemer providing the appropriate patch.

Added gray to the list of ANSI colors supported by logback. The relevant pull request was kindly provided by Craig P. Motlin.

The `discoverConnectionProperties()` method in class `ConnectionSourceBase` no longer leaks connections. This fixes LOGBACK-798 reported by Sayevskiy Viacheslav. Many thanks to Ivan (Wee-Willie-Winkie) who contributed the appropriate fix.

In logback-access, more correct determination of whether contents of an `HttpServletRequest` are URL encoded or not. The bug fix was submitted by David Schneider. The same issue was later independently reported by Grzegorz Kuligowski in LOGBACK-814.

Both `SocketAppenderBase` and `SimpleSocketServer` now use a socket factory to create sockets. These changes were asked in LOGBACK-815 and LOGBACK-816 by Carl Harris who also contributed the relevant patch.

### 15th of March, 2013 - Release of version 1.0.10

Upgraded the (optional) groovy dependency to version 2.0.7 (from 2.0.0).

The logger cache field in `LoggerContext` now uses a `ConcurrentHashMap` instead of a regular `HashMap`. This dramatically improves the speed of logger retrieval and incidentally fixes LOGBACK-142.

In `SyslogAppender` allow suffixPattern to begin with literal text. This issue was reported Bruno Polaco in LOGBACK-782 who also provided the relevant patch.

In order to reduce unnecessary boilerplate several common types and packages are now imported automatically. This feature was contributed by Joris Kuipers.

Computation of caller information now takes into account Groovy frames (if nunning under Groovy). This fixes LOGBACK-811.

### December 5th, 2012 - Release of version 1.0.9

Removed an erroneous compile-time dependency on Tomcat in the logback-classic module. This issue was reported by Arnaud Heritier.

### December 4th, 2012 - Release of version 1.0.8

#### logback-classic updated to use SLF4J version 1.7.2 instead of version 1.6.6.

The logback-classic module now uses SLF4J version 1.7.2 instead of version 1.6.6. This only impacts projects running under an OSGi platform as SLF4J versions 1.7.x and 1.6.x are 100% binary compatible.

Fixed incorrect `BufferStream` assignment after recovery in `ResilientFileOutputStream`. This issue was reported in LOGBACK-765 by David Markwick.

Fixed incorrect parsing of variables in case of colon character followed by a dollar character. This issue was reported in LOGBACK-744.

`SyslogAppender` now sends out the header line of stack traces. This issue was reported LOGBACK-411 and separately as LOGBACK-750.

A `StatusListener` implementing `LifeCycle` interface was not started if specified via the `logback.statusListenerClass` system property. This issue was reported in LOGBACK-767 by Adam Sokowicz.

In order to avoid duplication, automatic status printing will be disabled if the user explicitly registers a status listerner.

Added `OnErrorConsoleStatusListener` to print status messages on the error console, i.e. on System.err. This feature was requested in LOGBACK-292 by Abraham Lin.

Added `NopStatusListener` class which simply drops incoming status messages. By explicitly registering a `NopStatusListener` listener, automatic status printing can be turned off.

### 24th of August, 2012 - Release of version 1.0.7

#### Janino library upgraded to version 2.6.1.

As of Janino version 2.6.0, in addition to janino.jar, commons-compiler.jar needs to be on the class path as well. Please see the Janino setup instructions.

#### Groovy dependency upgraded to version 2.0.0.

Please see the Groovy setup instructions.

The code handling variable substitution has been completely re-written. As requested in LOGBACK-729, variables can be now be nested arbitrarily, even within the default value section. For example, `${a${b:-c}:-${d:-e}}` is now a valid logback variable expression yielding "e", assuming variables with the keys 'd', 'b' and 'ac' are undefined. The new variable substitution code is designed to be backward compatible with existing configuration files.

Substitution properties are now correctly recognized by scan and scanPeriod attributes of `<configuration>` element in configuration files. This fixes LOGBACK-396 reported by Oh Chin Boon

The color-related conversion words now set the default color correctly. Xu Huisheng provided the relavant patch.

Fixed a race-condition in `AsyncAppender` and its worker thread. This issue was reported in LOGBACK-720 by Arnd Hannemann who also supplied the relevant patch.

If a `PropertyDefiner` implements `LifeCycle`, then its `start()` method will now be invoked.

Added the includeCallerData property in `SMTPAppender` to precompute caller data before storing events for future transmission. This property addresses LOGBACK-734 reported by Patrick Hogarty.

### 7th of June, 2012 - Release of version 1.0.6

`SMTPAppender` now supports the retrieval of a `javax.mail.Session` resource from JNDI. This feature was requested in LBCLASSIC-332 by Hrotko Gabor.

Listeners passed to `statusListener()` method in `GafferConfigurator` (the groovy configurator) are now correctly started.

### 6th of June, 2012 - Release of version 1.0.5

`ConsoleAppender` can now activate the Jansi library for ANSI color code support on Windows systems. Unix-based operating systems such as Linux and Mac OS X already support ANSI color codes by default.

`PatternLayout` now supports composite conversion specifiers for coloring.

### 31st of May, 2012 - Release of version 1.0.4

Added `AsyncAppender` for asyncronous invocation of nested appenders. This was a long standing and popular request as attested by LBCLASSIC-177, LBCORE-92 and LBCLASSIC-242.

`SMTPAppender` now admits the asynchronousSending property, set to 'true' by default. However, it can be set to 'false' for synchronous email transmission. This property was requested in LBCLASSIC-323 by Patrick Houk.

It is now possible to set a system property called "logback.debug" in order to force printing of internal status messages on the console regardless of the value of the debug attribute found within the `<configuration>` element. This behavior was requested in LBCLASSIC-225 by Aaron Digulla with the relevant patch kindly provided by Antony Stubbs.

`MarkerFilter` now correctly recognizes nested markers. This issue was reported in LBCLASSIC-295 by Paolo Mazzoncini who also provided the relevant patch.

Fixed invalid multiple configuration warning when deployed under Weblogic. This issue was reported in LBCLASSIC-159 by Hontvári József and with the appropriate patch provided by Derek Mahar.

`SyslogAppender` now admits the throwableExcluded property allowing the exclusion of throwable data if so desired. This solves LBCLASSIC-327 reported by Don Faulkner.

`SyslogAppender` now admits the stackTracePattern property allowing the customization of the string appearing just before each stack trace line. This fixes LBCLASSIC-333 reported by Ingebrigt Berg who also provided the relavant patch.

`DBAppender` now supports SQLite. This feature was requested in LBGENERAL-53 by Tony Trinh who also provided the relevant patch.

### 4th of May, 2012 - Release of version 1.0.3

`PatternLayoutEncoder` class now admits the immediateFlush property (set to true by default). By setting this property to 'false', logging throughput can be quintupled, although your mileage may vary. This enhancement was requested in LBCORE-243.

In order to facilitate parsing of log files, logback can now output the pattern used for the log output at the top of log files as a header. This feature was requested by James Strachan in LBCORE-234.

`SMTPAppender` failed to transmit messages under JDK 1.5. After some investigation, Dave discovered that this was due to setting the `corePoolSize` parameter of the relevant `ThreadPoolExecutor` to 0. Setting `corePoolSize` to a higher value, e.g. 1, under JDK 1.5 solves the problem and fixes LBCLASSIC-323 reported by Lutz Huehnken.

`LevelChangePropagator` now retains references to j.u.l. loggers whose level it sets. This fixes garbage collection issues reported in LBCLASSIC-256 by Samuel Stanojevic who also provided the appropriate patch.

### 26th of April, 2012 - Release of version 1.0.2

#### Breaking change partially reverted in 1.0.3
By default `PatternLayout` will now output its pattern at the top of log files

This feature, although still available, is no longer enabled by default. See release notes for version 1.0.3 for details.

`ReconfigureOnChangeFilter` will avoid excessive syncronization in case of CPU intensive applications. This fixes LBCLASSIC-234, a recalcitrant bug reported by Uri Unger who also provided the key steps for reproducing it.

`RollingFileAppender` now creates missing directories for compressed archive files. This fixes LBCORE-169 reported by Tomasz Nurkiewicz with patches supplied by Paulo Andrade and Mats Henrikson.

`SizeAndTimeBasedFNATP` will now remove files with indexes higher than 99. It will also correctly compute the highest index value when an application is restarted. This fixes bug LBCORE-221 reported by Dieter Mueller and Dawid Chodura.

### 7th of March, 2012 - Release of version 1.0.1

Setting the debug attribute to true in the `<configuration>` element now registers a `OnConsoleStatusListener` with the `StatusManager`. Thus, problems occurring during the lifetime of your application, well after logback is initialized, can be reported when the debug attribute is set. This behavior is closer to what users expect.

Added new property the cleanHistoryOnStart to TimeBasedRollingPolicy. By setting this property to `true`, history removal will work as expected even in the case of short lived applications. This fixes LBCORE-226 reported by Bruce E. Irving.

It is now possible to specify multiple %d tokens in the file name pattern of TimeBasedRollingPolicy. Auxiliary %d tokens must be marked as such by passing the AUX parameter. This feature was requested in LBCORE-242 by Thomas Corte.

Logback now supports suppressed exceptions introduced in Java 7. This fixes LBCLASSIC-276.

`SMTPAppender` clears the relevant cyclic buffer before asynchronous transmission. This corrects LBCLASSIC-221 as reported by Chris Cheshire.

`SiftingAppender` will consider stale and consequently remove nested appenders which are closed or improperly started. This caters for the use case described in LBCLASSIC-316 by Guus Bloemsma.

`RequestLogImpl` can now lookup for the logback-access configuration file as a class path resource. This feature was requested in LBACCESS-26 by Marshall Pierce.

Updated the Janino dependency to version 2.5.16. In addition, the code checking for the availability of Janino on the class path was updated to take Janino 2.6 into account, thus fixing LBCORE-210.

### 1st of November, 2011 - Release of version 1.0.0

The logback-access module now targets Tomcat 7.x and Jetty 7.x & 8.x as its servlet container platforms. This fixes LBACCESS-17 reported by Grzegorz Grzybek.

#### Breaking change: properties are no longer automatically inserted into the context

Properties now have a scope. Previously, the definition of a property added it to the context. As of version 1.0, properties are local, i.e. transient by default. For further details, please refer to the documentation on properties.

Environment variables are now looked up during property substitution. This feature was requested in LBCORE-212 by Alexandre Garnier.

`SMTPAppender` now sends emails asynchronously.

Investigation of LBCORE-224 reported by Cesar Alvarez Nunez points to bug in the JVM rather than in logback. A workaround has been found by using `CopyOnWriteArrayList` instead of the apparently buggy `ReadWriteLock`.

In STARTTLS mode, "mail.smtp.auth" property is no longer set automatically. This fixes LBCORE-225 reported by Mark Woon.

Logback-access now supports conditional configuration. This fixes LBACCESS-27 reported by Marshall Pierce.

Logback-access now supports inclusion of configuration files. See the chapter about configuration in the logback's online manual for more information.

Added `ch.qos.logback.core.read` to "Import-Package" declaration in logback-classic's manifest file. This fixes LBCLASSIC-131 reported by Michal Prihoda and Thomas Jaeckle.

Fixed infinitely recursive calls in `AccessConverter#addError` methods as reported in LBACCESS-25 by Pierre Queinnec.

Fixed incorrect switch fallthrough while selecting between the H2 and HSQL dialects as reported in LBCORE-218 by Pierre Queinnec.

### September 21st, 2011 - Release of version 0.9.30

Archive removal can now deal with prolonged periods of application inactivity and application stop and restarts. The issue is described in LBCORE-147 reported by Rafael Diaz Maurin.

Logback-classic now supports printing stack traces "root cause first" instead of the standard "root cause last". See the documentation for %rootException converter for further details. The `%rootException` converter was contributed by Tomasz Nurkiewicz in relation with LBCLASSIC-217.

In the `ILoggingEvent` interface the `getMDC` method is now deprecated and replaced by `getMDCPropertyMap`. The latter method was already part of the `ILoggingEvent` interface in prior versions of logback-classic. Furthermore, the value returned by `ILoggingEvent.getMDCPropertyMap` can now be an empty map but never null.

`LoggingEvent` no longer assumes that `LogbackMDCAdapter` is the only possible implementation of the `MDCAdapter` interface. This fixes LBCLASSIC-275 reported by Chris Dolan.

`LogbackMDCAdapter` now synchronizes over its thread local map. This prevents `ConcurrentModificationException` from occurring while a child thread copies the map from the parent. This fixes LBCLASSIC-289 reported by Josh Oddman.

It is now possible to specify multiple destination addresses separated by commas in the the to property of `SMTPAppender`. This fixes LBCORE-213 reported by Alexandre Garnier who also provided the relevant patch. In previous versions of logback multiple destination addresses could only be specified by using multiple to properties. As of version 0.9.30 both comma separated addresses and multiple to properties are supported.

When debug attribute is set to true within the `<configuration>` element, status messages are printed on the console after Joran (re)configures logback. Previously, all status messages were printed. With this release, only status messages created during (re)configuration are printed. This change fixes LBCLASSIC-273 reported by Joern Huxhorn.

Single quotes within a date conversion specifier in filename patterns are now handled correctly. This fixes LBCORE-214 reported by Derek Libby.

### June 9th, 2011 - Release of version 0.9.29

Fixed LBCLASSIC-254, a performance issue in `LogbackMDCAdapter` as reported by Michael Franz.

Given that events reference a snapshot of the current MDC map, the snapshot should not be cleared upon invocation of the MDC.clear operation. This issue was reported in LBCLASSIC-253 by Tommy Becker and independently fixed by the changes designated to fix LBCLASSIC-254.

As reported by Deepak Vadgama in LBCORE-199, the entry in every zip file created by `FixedWindowRollingPolicy` had the same name. The issue was solved by adding a timestamp to the name of the entry in the zip files as suggested by a Benoit Xhenseval.

`ConfigurationWatchList` no longer emits an error message when it encounters a configuration file placed in a jar file, fixing LBCLASSIC-246 as reported by Joern Huxhorn. This release also fixes LBCLASSIC-247 reported by Michael Franz.

Logback now emits a clearer error message in case a conversion pattern misses a closing parenthesis or if an opening parenthesis is misplaced. This fixes LBCORE-193 reported by B. K. Oxley.

Fixed thread safety issue in LRUMessageCache reported in LBCLASSIC-255 by César Álvarez Núñez.

The AccessEvent class in logback-access module now implements the `IAccessEvent` interface. This fixes LBACCESS-12 reported by Joern Huxhorn.

### January 25th, 2011 - Release of version 0.9.28

#### Breaking change: In the Context interface, the previously misspelled property `bithTime` is now renamed as `birthTime`.

In the Context interface, the previously misspelled property `bithTime` is now renamed as `birthTime`. This is a backward-incompatible change. All pre-existing references to "bithTime" property now need to referenced as "birthTime".

Fixed issue 238 reported by Robert Elliot. `GEventEvaluator`'s start method now correctly sets the state of the instance.

`JaninoEventEvaluator` now expects Java blocks instead of boolean expressions. For even moderately complex logical statements, blocks can be more convenient to read or to write compared with boolean expressions. To ensure backward compatibility, existing boolean expressions are converted into blocks on the fly.

Corrected handling of null valued arguments by DBAppender. This fixes LBCLASSIC-239 reported by Artyom Kalita.

It is now possible to use the context birth time as the time reference for the `<timestamp>` element in configuration files.

Logback can now scan for included files as well. This solves LBCLASSIC-245.

### December 22nd, 2010 - Release of version 0.9.27

Added a new section in the documentation about real-world inspired recipes.

`PatternLayout` now supports compound conversion words of which "%replace" is one example. This change involved a significant re-write of the pattern tokenizer, the pattern parser and the pattern compiler. However, the changes should be backward compatible as far as users are concerned.

The to option of SMTPAppender now admits a pattern and is evaluated dynamically.

`TeeServletInputStream` no longer chokes on input over 8K in size. This fixes LBACCESS-10 as reported by Augusto Rodriguez.

`TeeFilter` now takes include and exclude parameters so that it can be enabled or disabled by host. This solves LBACCESS-15.

Fixed LBCLASSIC-231 as reported by Jeff Skjonsby. When configuring `SizeAndTimeBasedFNATP`, `GaggerConfigurator` (Groovy) will no longer throw a `NullPointerException`.

Every context now returns its own name when asked for the property `CONTEXT_NAME`. This fixes LBCORE-178 as requested by Michael Osipov.

### 20th of October, 2010 - Release of version 0.9.26

Fixed LBCLASSIC-183 as reported by Anthony Whitford. Upon application restart, Tomcat should no longer complain about ThreadLocal variables created internally by logback.

`SMPTAppender` now lets users to set a custom buffer size for the outgoing messages. This fixes LBCORE-170 as requested by Peter Royal.

When stopped, `RollingFileAppender` now calls `stop()` on its policy objects, fixing LBCORE-114 reported by Anders Wallgren.

Added mapping for OFF and ALL levels in `JULHelper` as requested in LBCLASSIC-226 by Christian Brensing.

### October 13th, 2010 - Release of version 0.9.25

Logback-classic now supports propagation of level changes from logback-classic onto the j.u.l. framework. This significantly reduces the performance impact of disabled log statements making it reasonable for real-world applications to use the jul-to-slf4j bridge.

The `<appender-ref>` element now supports variable substitution, thus fixing LBCLASSIC-224 as reported by David Harrigan.

As reported in LBCORE-164, `SizeAndTimeBasedFNATP` would cause previous logging files with indexes over nine to be overwritten on application restart. This complex bug was reported and precisely diagnosed by Dieter Mueller. He has also proposed a fix which was subsequently adopted as is.

### June 30th, 2010 - Release of version 0.9.24

Fixed NullPointerException thrown by `MDCBasedDiscriminator` in case the MDC map is null.

Fixed issue with `SizeAndTimeBasedFNATP` in presence of application stop/restart and non-null file property. This issue was reported by Tom Liu in LBCORE-131.

### June 29th, 2010 - Release of version 0.9.23

Fixed Groovy runtime dependency problem with ReconfigureOnChangeFilter, i.e. the auto-scan filter, when using non-groovy configuration files. This problem was reported in LBCLASSIC-214 by Alvin Chee.

Fixed `MDCBasedDiscriminator` so that it supports deferred processing. This issue was reported in LBCLASSIC-213 by Torsten Juergeleit.

### June 21st, 2010 - Release of version 0.9.22

Logback now supports configuration files written in Groovy which are more convenient than configuration files written in XML. We have also developed a tool to automatically migrate your logback.xml files to logback.groovy.

Inspired by the functionality offered by `SiftingAppender`, `SMTPApppender` now can track multiple buffers according to selection information returned by a discriminator.

Fixed synchronization issue in `ConsoleAppender` as reported in LBCORE-158 by David Roussel who also supplied a corrective patch.

### May 8th, 2010 - Release of version 0.9.21

SLF4J dependency upgraded to 1.6.0

Fixed concurrency problem in `SiftingAppender` as reported in LBCLASSIC-203 by Ellen Strnod.

Added GEventEvaluator which processes boolean expression written in the Groovy language.

Fixed rollover problem occurring when the target directory was missing as reported in LBCORE-151 by Torsten Juergeleit. A closely related problem was reported in LBCLASSIC-167 by Rick Janda.

### April 2nd, 2010 - Release of version 0.9.20

Fixed issue related to charsets in `LayoutWrappingEncoder` not being recognized in config files.

Logback now supports conditional processing of configuration files.

A new extension point for defining properties on the fly has been added. The code for this enhancement was provided by Aleksey Didik in LBCLASSIC-182.

Logback now provides an answer to the longstanding logging separation problem for static logger references in shared libraries. This fixes LBCLASSIC-166 and LBCLASSIC-87.

Removed the previously deprecated `getFirstFilter` method in `FilterAttachable` interface.

### March 24, 2010 - Release of version 0.9.19

#### Breaking change: FileAppender now expects an Encoder

In response to LBCORE-128, `WriterAppender` has been renamed as `OutputStreamAppender`, `FileAppender` now sub-classing the latter. `OutputStreamAppender` and sub-classes now take an `Encoder` instead of a `Layout`.

Contrary to layouts which simply transform a logging event into a String, an encoder is responsible for writing the actual event or more accurately the representation of the event onto the output stream. The role of the enclosing appender is now limited to managing the output stream (opening/closing) but not writing actual contents onto the stream. This change will require modifications to existing configuration files. We hope to make up for this inconvenience with cool new features which are only possible using encoders. During a transition period, layouts passed as parameter will be automatically wrapped by an encoder so that configuration files in the old format (using a layout instead of encoder) will continue to work unmodified.

#### Breaking change: DBAppender in logback-classic expects four additional columns

Instead of lumping log request arguments into a field, `DBAppender` (in logback-classic) now outputs up to four arguments in the logging request in separate columns, named `arg0`, `arg1`, `arg2` and `arg4`. This solves LBCLASSIC-187 reported by Greg Thomas.

Existing databases can be migrated to the new table structure by altering the existing tables. Here is how it would be done in PostgreSQL and MySQL.

    ALTER TABLE logging_event ADD COLUMN arg0 VARCHAR(254);
    ALTER TABLE logging_event ADD COLUMN arg1 VARCHAR(254);
    ALTER TABLE logging_event ADD COLUMN arg2 VARCHAR(254);
    ALTER TABLE logging_event ADD COLUMN arg3 VARCHAR(254);

In Oracle:

    ALTER TABLE logging_event ADD arg0 VARCHAR(254);
    ALTER TABLE logging_event ADD arg1 VARCHAR(254);
    ALTER TABLE logging_event ADD arg2 VARCHAR(254);
    ALTER TABLE logging_event ADD arg3 VARCHAR(254);

`FileAppender` and derived classes can now gracefully deal with IO failures and recover quickly after the original cause of the IO failure is corrected. For example, if the log file is located on a network-attached storage (NAS), and the connection to the NAS server is lost, `FileAppender` and derived classes will recover quickly after the connection to the server is re-established.

The packages under `ch.qos.logback.classic` namespace no longer depend on `org.slf4j.impl`. This fixes LBCLASSIC-184 reported by Gunnar Wagenknecht.

Fixed LBCLASSIC-193. `SyslogAppender` will no longer shutdown when messages over 256Kb cause an `IOException`.

Added OnMarkerEvaluator which evaluates to true in the presence of user-specified markers. When used with `SMTPAppender`, it can trigger an outgoing email message when an event matches user-specified marker.

Request header names in AccessEvent (logback-access) are now stored in a case insensitive way as specified in RFC 2616. This prevents compatibility issues, in particular with recent versions of Tomcat which store request header names in lower-case.

Fixed LBCORE-134 reported by Michael Franz. While reading configuration files (in XML), the event handler will correctly process body text, in particular spaces, even when delivered in multiple chunks. The previous behavior of trimming leading and trailing white space has been preserved. Moreover, body text consisting of white space surrounding child elements is ignored.

`SiftingAppender` now exposes its `AppenderTracker`. Moreover, the `stopAndRemoveNow(String key)` method was added to `AppenderTracker`, allowing immediate removal of a nested appender.

Fixed LBCORE-130. `FileNamePattern` no longer treats parenthesis as special.

The CharsetEncoder property in `SMTPAppender` can now be accessed and set from configuration files. This fixes LBCLASSIC-194.

Instead of sending its output to the System.out/err reference that was effective at initialization, `ConsoleAppender` will now seek the most current System.out/err reference and send its output there. This fixes LBCORE-143 as reported by Tom SH Liu.

DBAppender now outputs exception class and message. It will also output root causes, fixing LBCLASSIC-170 reported by Tomasz Nurkiewicz.

You can now override table and column names in DBAppender. This feature was requested in LBCLASSIC-188 reported by Tomasz Nurkiewicz.

Fixed missing EVENT_ID column problem on PostgreSQL as reported in LBCORE-126 by Brian Edwards.

Event id values in DBAppender are now 64bit instead of 32. This change was requested in LBCLASSIC-198 by Michael Lynch.

Added Sybase SQLAnywhere support in DBAppender. This feature was requested by Michael Lynch in LBCLASSIC-197.

Added H2 support in DBAppender.

Fixed LBSITE-36 reported by John Jimenez.

### 3rd of December 2009 - Release of version 0.9.18

After a very long investigation resulting in somewhat a better understanding of licensing issues, logback is now dual-licensed under the EPL 1.0 and LGPL 2.1.

Due to a clerical error LBCORE-26 has re-raised its ugly head. It has now been tamed for good.

Fixed Private-Package and Export-Package sections in logback-classic.jar MANIFEST as reported in LBCLASSIC-165 and LBCLASSIC-121 by applying the relevant patches supplied by Hugues Malphettes.

Made the OSGi import declarations for Janino and javax optional as proposed by David Varnes in LBCORE-101.

`ReconfigureOnChangeFilter` did not pick up changes for configuration files containing spaces. This issue was reported in LBCORE-119 by Anders Wallgren.

Added tests cases which run logback artifacts as bundles within Felix. This should solve a series of problems related to OSGi.

When ill-formed configuration files fragments were included in another configuration file, the included file was not closed correctly. This issue was reported in LBCORE-122 by Michael Franz.

JaninoEventEvaluator now passes the throwable associated with an event as a `java.lang.Throwable` instead of an `IThrowableProxy`. This fixes LBCLASSIC-155 as reported by Hontvári József. See EvaluatorFilter documentation for more details.

The name of the log file nested within .zip archives was incorrectly set to be that of the tmp file logback creates during compression. Anders Wallgren reported and posted an appropriate patch for this problem in LBCORE-98. The nested file is now named after the zip archive file. Analysis showed that this was an appropriate strategy in all the cases we considered.

Fixed LBCLASSIC-149. The ContextNameConverter now correctly uses the context name of the event instead of its own context name.

When a logger is named after an inner class, the '$' is used as a separator, instead of the usual '.'. This fixes the level inheritance issue described in LBCLASSIC-102 and as reported by Joern Huxhorn.

Fixed deadlock issue observed with appender which invoke loggers as reported in LBCLASSIC-154 by Andrew Perrine and debugged by Ralph Goers who also proposed the relevant patch.

### 9th of August 2009 - Release of version 0.9.17

`PackagingDataCalculator` now correctly deals with `NoClassDefFoundError` thrown by class loaders. This fixes LBCLASSIC-125 reported by Roland Klein and independently by Didier Besset.

In configuration files, all tags names associated with explicit actions are now case-insensitive. This should diminish case-related errors users may make when writing configuration files. Tag names associated with implicit actions which are closely linked to the actual Java class being configured, still need to follow the camelCase convention. If you are unsure which case to use for a given tag name, just follow the camelCase convention for tag names which should be correct in most cases.

It is now possible to create uniquely named files by timestamp. Such files are appropriate for log files associated with batch applications. This enhancement fulfills LBCORE-91 as requested by Rick Beton and Szel Zoltan.

Append mode is now mandatory in `RollingFileAppender`. This was already the default and truncation mode is unreasonable in most cases. For example, in truncate mode when an application stops and is quickly re-started, any pre-existing log file for the current period will be lost.

The `activeFile` field in `RollingFileAppender` is now properly updated, fixing LBCORE-90 as reported by Valery Shorin.

The `TimeBasedTriggeringPolicy` has been heavily refactored. It is now possible to trigger rolling simultaneously by time and by size, fixing LBCORE-61.

Fixed LBCLASSIC-145 reported by Joern Huxhorn. The `LoggingEventVO` class now correctly populates its callerData field if the original `ILoggingEvent` already has it.

### 15th of July 2009 - Release of version 0.9.16

In addition to nifty new features, this release contains several important internal changes. Given the importance of some of those internal changes, this release may be less stable than previous logback releases.

In logback-classic, `LoggingEvent` now implements the `ILoggingEvent` interface. All logback-classic components expect to process `ILoggingEvent` instances. Moreover, events which sent to a remote host are now of type `LoggingEventVO`.

Logback-classic will now automatically re-configure itself when its configuration file is modified. This enhancement was requested in LBCORE-59 by Michael Osipov.

FileAppender and its derived class RolllingFileAppender are now based on a finer-grain synchronization model. This change is aimed at reducing various synchronization related bugs, namely LBCLASSIC-135 and its various sub-tasks.

Fixed a bug in the localLevelReset() method in the `Logger` class which inadvertently used the DEBUG_INT value in the org.slf4j.spi.LocationAwareLogger interface instead of the DEBUG_INT value in ch.qos.logback.classic.Level class. The issue was first identified by Andy Ruch in a message to the logback-user list

If the logger name had 12 or more segments, a the logger conversion specified would throw an `ArrayIndexOfBounds` exception. Lukas Zapletal has kindly reported this problem in LBCLASSIC-110 and provided a test case.

A new discriminator class called "ContextBasedDiscriminator" allows SiftingAppender to separate logging based on the context name. This fits nicely with the requirements expressed in LBCLASSIC-117 by Rick Janda.

When a context is reset, then its object and property maps are now cleared. This fixes LBCORE-104 reported by Johan Bos.

Fixed LBCORE-105. Configuration files placed in jar files will no longer lock the jar file. This issue was initially reported for log4j in bug 47465 Mark Thomas.

Fixed LBCORE-94. While configuring a RollingFileAppender, if the File property is declared after any rolling or triggering policies, then logback will now generate an error status message.

Fixed LBCLASSIC-134 reported by Darryl Smith. `DuplicateMessageFilter` will now behave correctly when invoked via `Logger.isXXXEnabled` methods.

Fixed LBCORE-107, incorrectly set context information for the `NestedBasicPropertyIA` instance in Joran, reported by Lóránt Pintér.

Fixed LBCLASSIC-109, reported by Andrew Ruch when a logger context was reset, the trace level was erroneously enabled.

### 12th of February 2009 - Release of version 0.9.15

When the reset() method in `LoggerContext` is called, registered turbo filters are first stopped before being unregistered. This fixes LBCLASSIC-89 reported by Alexis Morillo.

Added a servlet for viewing internal status messages as an HTML table. Two separate implementations are available; one for logback-classic and the other for logback-access.

Added the `clear()` method to the `StatusManager` interface. After reconfiguration, it may be desirable to clear the status list maintained by a `StatusManager`. This change was requested by Alexis Morillo in LBCORE-77.

Fixed problem LBCLASSIC-104 related to loss of MDC information in deferred logging events.

Fixed issue LBCLASSIC-101. Logback jar files now include full OSGi bundle information in their manifests. This information is automatically added by Apache Felix' Maven bundle plug-in. The generated manifest files contain an appropriate Bundle-RequiredExecutionEnvironment directive, fixing LBGENERAL-8.

The setter and getter methods for the layout property in `AppenderBase` class now have reasonable default implementations, instead of nop previously. This change was requested by Thilo Tanner in LBCORE-56.

Added log4j.dtd compatible `XMLLayout` as requested in LBCLASSIC-22.

New chapter on Joran.

### 29th of December 2008 - Release of version 0.9.14

Corrected a serious dead-lock problem occurring during configuration. It was reported in LBCLASSIC-81 by Holger Mense.

Corrected thread leakage observed with `TimeBasedRollingPolicy`'s `AsynchronousCompressor`. This bug was reported in LBCORE-78 by Szel Zoltan.

Added DuplicateMessageFilter, a turbo filter which detects duplicate messages, and beyond a certain number of repetitions, drops repeated messages.

Added a new appender called `SiftingAppender`. As its name intimates, a ``SiftingAppender`` can be used to separate (or sift) logging according to a given runtime attribute. For example, `SiftingAppender` can separate logging events according to user sessions, so that the logs generated by each user go into distinct log files, one log file per user.

`BasicStatusManager`'s internal buffer is now split into two parts, the header part and the tail part. The header part stores the fist H status messages whereas the tail part stores the last T messages. At present time H=T=150, although these values may change in future releases.

Fixed `NullPointerException` thrown when calling `setContextMap` on a fresh MDC. Issue was reported by Francois Terrier.

Evaluators are now wired into an appender automatically (implicit rules) without the help of `EvaluatorAction`. EvaluatorAction is now only needed for global evaluator elements. It follows that name attribute is necessary only for global evaluators. Embedded evaluators no longer need a name. This change fixes LBCLASSIC-100. In addition, `EvaluatorAction` has been modified to accept evaluators of any type and not just instances of `JaninoEvaluator`.

Logback-classic default configuration process will now automatically print status data on the console in case of warnings as well as errors. Previously, status data was printed only in case of errors.

`ContextInitializer` will now print the url of the configuration it is using. This should help reduce confusion when multiple config files are found on the class path. This change resolves LBCLASSIC-55 reported by Anton Tagunov and Henric Larsson.

In case multiple configuration files are found on the class path, `ContextInitializer` will now emit a warning. This fixes LBCLASSIC-85 filed by Szel Zoltan.

`HTMLLayout` now honors custom conversion words, thus fixing LBCORE-74 as reported by Natan Cox.

Fixed LBCORE-69 as reported by Andrey Rybin. `SMTPAppenderBase` now has support for charset encodings so that email messages can contain characters beyond US-ASCII.

`SMTPAppender` in logback-classic now defaults to `OnErrorEvaluator` instead of a janino-based evaluator. Thus, by default `SMTPAppender` no longer depends on Janino.

Added UnsynchronizedAppenderBase class based on Ralph Goers' contribution in LBCORE-58. Note that `AppenderBase` remains unchanged. Appenders which need to handle synchronization on their own can do so by deriving from `UnsynchronizedAppenderBase`.

### 5th of December 2008 - Release of version 0.9.13

A `NullPointerException` was being thrown when a the level of a logger was set to null. The logger in question had to have children. This problem was reported in LBCLASSIC-91 by Mateusz Jedruch.

### 4th of December 2008 - Release of version 0.9.12

Fixed bug LBCORE-26 reported by Tsutomu YANO and independently by Hontvári József and Gamaliel Amaudruz. `RollingFileAppender` when used in conjunction with `DateBasedRollingPolicy` will rollover existing log files at initialization if their timestamp warrants it.

Added support for file appending in prudent mode. Thus, multiple `FileAppender` instances running on multiple JVMs can safely write to the same log file. With certain limitations, prudent mode extends to `RollingFileAppender`.

Fixed LBCLASSIC-83. It is now possible to set the level of a logger to null, even if it was previously set to a non-null level. Previously, a `NullPointerException` would be thrown.

In response to LBCLASSIC-61, LBCLASSIC-33, LBCLASSIC-24 and LBCLASSIC-14 `JMXConfigurator` has been redesigned.

Fixed LBGENERAL-22. The log4j.properties translator web-application has been significantly refactored.

Fixed improvement request LBCLASSIC-59 relation to StatusListeners, originally submitted by Anton Tagunov.

The logger and class name converters now consider zero as having special meaning, and will return the simple class name, removing the package name prefix. This feature was asked by Silvano Maffeis.

In response to LBCLASSIC-54 support for turbo filters has refactored. The present code is safe under concurrent access while still offering good performance.

Fixed LBCORE-43 reported by Bruno Navert. Configuration files can now look up property files from classpath resources.

Fixed LBCLASSIC-86 related to `AccessControlException` thrown when run in a JVM with a `SecurityManager`.

Invoking the `LoggerContext.reset()` method resets logger levels to their default value, that is `DEBUG` for the root logger and `null` for all other loggers. This was requested in LBCLASSIC-90 by Mateusz Jedruch.

Fixed bug LBCLASSIC-69 reported by Anton Tagunov. The LevelToSyslogSeverity now correctly handles the TRACE level.

Fixed bug LBCLASSIC-57 reported by Anton Tagunov. SyslogAppender could overwhelm the Syslog server with very large messages. SyslogAppender now limits its message size to 256K.

Logback now supports setting the logger context name as well as inserting variables stored in JNDI as properties.

Fixed issue LBCLASSIC-49 reported by Oliver Lietz. The getLogger() method in `LoggerContext` class will now throw an `IllegalArgumentException` when invoked with a null argument.

### 28th of October 2008 - Release of version 0.9.11

Fixed LBCLASSIC-77 reported independently by Gianni Doe, Yannick Haudry and Yossi Shaul. The childValue() method of `CopyOnInheritThreadLocal` class part of MDC code no longer throws a `NullPointerException`.

### 27th of October 2008 - Release of version 0.9.10

In case of errors during initialization, logback-classic now automatically prints out its internal status. This has been a frequently requested feature.

The LogbackValve in logback-access (ensuring integration with Tomcat), will now systematically print its internal status upon initialization, unless told to be quiet. This greatly helps troubleshooting the configuration of logback-access under Tomcat.

Fixed bug 147 which occurred when the user inadvertently attempted to set the layout of a `SyslogAppender`. The code now actively prevents this. Documentation has been updated to reflect the change.

Fixed bug LBCLASSIC-56 originally reported by Michel Colette. Backslash characters are now correctly interpreted in filename patterns.

The TurboFilterChain in a LoggerContext is now cleared when the `reset`() method is called. This problem was reported on May 1st, 2008, by Julia Hu on the logback developers list.

Fixed issue LBCORE-48. During rollover, compression of large files would bring all logging to a halt. In this latest release, the rolled over file is first renamed, which is a relatively fast operation, and only then is the renamed file compressed asynchronously (in a separate thread).

Fixed issue LBCORE-11. It is now possible to instruct TimeBasedRollingPolicy to delete old files, thus controlling then number of archived log files.

Fixed issue LBCORE-42. If the parent directory of the log file does not exist, then FileAppender will create it, including any necessary but nonexistent parent directories.

Fixed LBCORE-15 reported by Klaus Unger and others. DBAppender should now work with Oracle 9, 10g and 11g, regardless of the JDBC driver type used.

Fixed issue LBCORE-17 reported by Thorbjørn Ravn Andersen. Logback now relies on Geronimo JMS API specifications instead of Sun's JMS API specification, the latter requiring manual installation. With Geronimo JMS, logback can be built using Maven without needing to manually install any dependencies.

Fixed issue LBCORE-23. In PatternLayout, parenthesis can be used to group conversion patterns. It follows that the '(' and ')' carry special meaning and need to be escaped to be used as literals. This is now properly documented.

The location of the default configuration file can be specified by a system property. This feature was requested in LBCORE-32 by Ted Graham, Matt Fowles, Ivan Biddles and Ralph Goers.

Fixed issue LBCORE-55 reported by Natan Cox. `WriterAppender` now outputs its presentation footer and file footer in the the correct order.

Fixed issue LBCORE-27 reported by Peter Royal. `SMTPAppender` now outputs its presentation footer and file footer in the the correct order.

Fixed issue LBCLASSIC-67 reported by Alessandro Fustini. SMTPAppender now correctly configures the layout used to format the subject line of the outgoing email. It no longer appends a lengthy stack trace to the subject line.

Fixed issue LBCLASSIC-68 reported by Gili Tzabari. In environments where the TCCL (Thread Context Class Loader) was not set, logback was unable to located its default configuration files. Logback now uses the class loader that loaded logback itself to locate its resources instead of the TCCL. This approach is simpler and deemed to cover more environments, i.e. more widely applicable.

Fixed issue LBGENERAL-24 reported by Hung Tang. SMTPAppender now supports plain username/password authentication as well as both the STARTTLS command and SSL connections.

Fixed issue LBCLASSIC-48 reported by Peter Royal. SyslogAppender now correctly outputs hours as 0-23 and not as 1-12 as previously.

Added a new TurboFilter called DynamicThresholdFilter which can filter events depending on MDC values based on a variety of criteria such as company name, product or the end user. This filter was contributed by Ralph Goers in LBCLASSIC-53.

### 26th of March 2008 - Release of version 0.9.9

MDC data in now inherited by child threads. This behaviour was already specified in the javadocs. The issue was raised by Martin Benda in bug 64 and independently by Peter Huber.

Logback no longer includes retro-weaver generated jars for JDK 1.4. There seems to be little interest in JDK 1.4 builds. Calling retro-weaver increases logback's build time by a few seconds each time – seconds in which we can do more productive things.

Fixed bug 104, silly but but nonetheless serious copy-and-paste errors in the c.q.l.classic.Logger class, reported by Joern Huxhorn.

Having been replaced by `SimpleSocketServer`, the `SocketServer` class has been removed.

Fixed bug 105, sockets created by `SocketAppenderBase` is now closed, reported by Joern Huxhorn. More generally, `SimpleSocketServer` is much more careful to track open client connections and to close them.

Fixed bug 110 in relation with the `requestParameterMap` field in `AccessEvent` - reported by Joern Huxhorn.

Fixed SLF4J bug 66 in relation with caller data when using log4j-over-slf4j - reported by Frnack Routier.

Fixed bug 129 reported by Michael Franz. As a result, Joran now supports nested as well as multiple file inclusions.

Fixed bug 100 reported by Joern Huxhorn. At serialization time, object array passed as parameter, when the LoggingEvent is are now serialized as strings.

Fixed bug 109 reported by Joern Huxhorn. There should no longer be any NullPointerExceptions thrown by deserialized `AccessEvent` instances.

Fixed bug 8 reported by Sebastien Pennec. The documentation has been updated to reflect the fact that that in the context of conversion patterns the percent sign carries special meaning, in order to include the percent sign as a literal, it must be escaped with a backslash.

Fixed bug 52 reported by Kenichi Masuko. The bug has been fixed on March 8th, 2007. Starting with this release, Joran will support the injection of any enum type, not just `FilterReply`.

### 22th of August 2007 - Release of version 0.9.8

This version of logback synchronizes with SLF4J version 1.4.3. In particular, logback now natively supports SLF4J's MDC API introduced in SLF4J version 1.4.1. If you are using SLF4J version 1.4.1 or later please make sure upgrade to logback version 0.9.8 or later.

Fixed a number of documentation related bugs, in particular bug 90 reported by Luc Maisonobe and bug 88 reported by Sebastian Davids.

It is now possible to include configuration file fragments (in XML) as a resource. Previously, it was only possible to include a file by specifying a path to a file or a URL. This feature was requested by Michael Newcomb in bug 89.

Fixed caller data extraction problem as reported in bug 78 by Hans van der Meer.

The LoggingEvent class' constructor now correctly takes into account the argument array passed by the user. This problem was reported in bug 85 by Robert Christian.

### 29th of May 2007 - Release of version 0.9.7

This release corrects packaging bugs 75 and 76 related to the migration of logback to SLF4J version 1.4.0. There are no other changes.

### 23rd of May 2007 - Release of version 0.9.6

Logback is now aligned and compatible with SLF4J version 1.4.0, thus correcting bug 73 as reported by Andy Gerweck.

Fixed `NoClassDefFoundError` problem when running under JDK 1.4 as reported by Brian Suksomwong.

Fixed bug 63 as reported by La Canea Rosario. Calling log4j (bridge) with the trace level will no longer cause an IllegalStateException to be thrown.

Fixed bug 70 as reported by Dirk Ooms. The %throwable conversion word is now recognized as documented in the logback manual. Moreover, the manual now mentions the %nopex word which can be used to force `PatternLayout` to ignore the exception contained in the logging request.

As in most releases, the documentation has been improved.

### April 2nd, 2007 - Release of version 0.9.5

Fixed methods `isInfoEnabled`, `isWarnEnabled` and `isErrorEnabled` methods in `ch.qos.logback.classic.Logger` class which failed to work correctly. This bug was reported today by Pavel Kral on the slf4j-user list.

Contrary to previous versions of logback, the various Logger.isXYZEnabled(Marker) methods now take into account the marker information passed as parameter.

As discussed in bug 54, during automatic initialization, it makes better sense to first check for logback-test.xml file and only if that fails, to check for logback.xml. Maven2 will guarantee that the logback-test.xml file, if places under test/resources will not be included in the artifact it produces.

### March 29th, 2007 - Release of version 0.9.4

Significant bug fixes made to `c.q.l.access.TeeFilter` and Co. Images and other binary files are now intercepted and replayed correctly. As for "x-www-form-urlencoded" post requests, their input buffer is left untouched. In a best-effort attempt, the input buffer for "x-www-form-urlencoded" post requests is later reconstructed through the request parameters. However, it may differ from the original buffer.

The logback team released today the first version of a plugin for Eclipse that allows developers to visualize logs generated by a running application. It offers several nice features. Please check the console plugin-in guide for more details.

### March 20th, 2007 - Release of version 0.9.3

Includes in configuration files are now supported by Joran, logback's configuration framework. A file can contain an include element that has a file or url attribute pointing to a configuration file. See the chapter about configuration in the logback's online manual for more information.

Corrected bug 53 reported by Wilkins Poe. There is now a dependencies page that shows the requirements of each of logback's modules.

After a discussion on the SLF4J mailing list started by Franck Routier, a correction has been made when logging using the JCL104-over-slf4j module. Logback now correctly shows the caller location information.

As in most logback releases, the documentation has been improved.

### March 5th, 2007 - Release of version 0.9.2

The documentation is now in the docs/ directory to allow an easier access to the logback manual and website for offline viewing.

### March 5th, 2007 - Release of version 0.9.1

Logback-class now depends on SLF4J version 1.3.0 instead of 1.2.

Numerous improvements to the documentation.

Bug #46 reported by Mark Renyolds has been fixed. The `TimeUtilTest` should now run fine under any time zone.

Bug #45, also reported by Mark Reynolds, has been fixed. There should be no `ClassCastException` thrown anymore when passing an `Object` to the printing methods using the log4j-bridge module.

### January 31st, 2007 - Release of version 0.9

This version contains a new component, namely the `ContextSelector`, that provides context separation and management when logback is used by several web-apps running under the same server. A new chapter was added to the logback manual to detail the use of the `ContextSelector`, along with its associated components.

The `JMXConfigurator` has been improved. It now shows the context's Status objects, which lets users check the internal state of logback.

The logback manual's chapter 2, about logback's architecture, has been updated with two sections: Under the hood and Performance.

### January 23th, 2007 - Release of version 0.8.1

This version contains new components in the Access module, allowing users to display the full HttpServletRequest or HttpServletResponse of an access event.

The documentation section has been updated. The short introduction was split into the chapter 1 and chapter 2 of the logback manual. The chapters about Appenders and Layouts have been updated to document new components of logback.

A demonstration webApp presenting logback's major components is available. A document explains how to run it, and provides a step-by-step visit of the demo.

A first translation of logback jars to JDK1.4 is present in this release.

### January 12th, 2007 - Release of version 0.8

This version contains a whole new chapter, namely Chapter 3, about logback configuration. Several other documentation pages have been improved.

Logback now uses Generics in many components.

Several new components have been added to logback. A JMX Configurator now allows users to see and modify loggers or reload configuration among other possibilities. A document about this configurator is available in the corresponding section of the site. We'd like to thank Sebastian Davids for his ideas and contributions to this component.

A JMSTopicAppender and JMSQueueAppender are now available, as well as two new filters: LevelFilter and ThresholdFilter. A refactoring was done in the filters objects to ease the implementation of custom filters.

### December 19th, 2006 - Release of version 0.7.1

Version 0.7.1 of logback has been released.

This version contains more detailed information about logback access module, and its JMX components. A dedicated page explains how to configure and use logback access in Tomcat and Jetty, and access some of its components via JMX.

### December 18th, 2006 - Release of version 0.7

Version 0.7 of logback has been released.

Logback now ships with a new module: log4j-bridge. This new module can be used to intercept log4j calls and redirects them to logback components. More information about this module can be found in the corresponding documentation page.

The documentation has been vastly updated. Two new chapters, namely Filters and MDC, are available in the manual section.

### November 30th, 2006 - Release of version 0.6

Version 0.6 of logback has been released.

Logback classic now supports automatic configuration, allowing test and production environment configuration. `TurboFilters` make their first appearance in a logback release. They provide ultra-fast filtering possibilities. The logging context now supports listeners which will be contacted each time the context is reset or started. `SMTPAppender` allows for much more flexible configuration than before.

In logback access, new Appenders are available, namely `SocketAppender` and `DBAppender`. Logback access now supports filtering and event evaluations. A `CountingFilter` has been added. It provides statistical views of server access, reachable via JMX.

The documentation has also been improved. A complete new chapter has been added about Appenders, the short introduction to logback classic has been updated and a new module, containing many configuration examples has been added.

Logback now uses continuous integration in its development.

Tests have been improved, many new have been added. This release also provides some bug fixes.

### October 26th, 2006 - Release of version 0.5

Version 0.5 of logback has been released.

This release offers a important improvements in Joran. In particular, Joran can now replay configuration elements.

As in the previous release, a major area of work is the documentation which is being continuously improved.

### October 9th, 2006 - Release of version 0.4

Version 0.3 of logback has been released.

This release includes an improved access module, with specific implementations for the Jetty and Tomcat servers. Documentation was also added to show how to integrate logback-access with Jetty.

As for the classic module, several appenders and layouts have been added or improved. The error reporting of logback has also been enhanced, presenting the user with a link to an online page explaining possible reasons for the error.

Joran documentation was added, with examples in the core module.

### September 8th, 2006 - Release of version 0.3

Version 0.3 of logback has been released.

This release offers several new Appenders, support for Mapped Diagnostic Context, improved tests and documentation

In response to a bug report by Rickard Nilsson on the logback mailing list, a bug affecting parametrized logging was fixed.

We also released a PropertiesTranslator webapp that converts log4j.properties files to joran configuration files (in XML format).

### August 23th, 2006 - Release of version 0.2.5

Version 0.2.5 of logback has been released.

This release offers better documentation, with a number of corrections made in the short introduction to logback-classic.

### August 15th, 2006 - Release of version 0.2

Version 0.2 of logback has been released.

It offers better tests, some more functionality, and enhanced documentation. We also improved the site design to make it simpler and more efficient.

### July 26th, 2006 - Release of version 0.1

Version 0.1 of logback has been released.

### February 9th, 2006 - Logback web-site goes live

The logback web-site goes live on the 9th of February. At its present state, it is pretty primitive but updates will follow.