build(deps): bump ch.qos.logback:logback-classic from 1.6.3 to 1.6.4

[dependabot]

Bumps ch.qos.logback:logback-classic from 1.6.3 to 1.6.4.

Release notes

Sourced from ch.qos.logback:logback-classic's releases.

Logback 1.6.4

2026-09-24 Release of logback version 1.6.4

• Variable substitution is again applied to the scan attribute of the <configuration> element. The scanning refactoring in version 1.5.27 had dropped substitution, so values such as ${logback.scan.enabled:-true} were no longer resolved. As before version 1.5.27, an unrecognized non-empty value turns scanning on. The same substitution now applies to the scan attribute of <propertiesConfigurator>. This regression was reported in issues/1065 by vaibhavjain2.

• OutputStreamAppender and FileAppender now handle stateful encoders. The Encoder interface has a new default method called isStateful(), which returns false. An encoder that keeps state between calls to encode() can return true. For such encoders, the appender holds its write lock while encoding and while writing, so the output of concurrent appends cannot interleave. Stateless encoders still encode outside the lock, so their performance does not change. Existing encoders need no changes.

• Several race conditions in OutputStreamAppender and FileAppender were fixed. The appender is now marked started and the encoder header is written while the same lock is held, so a concurrent append can no longer write an event before the header. After acquiring the lock, the appender checks again whether it has been stopped, so no event is written after the footer. In prudent mode, FileAppender now encodes and writes each event while holding the lock.

• Fixed a data race on the logger count in LoggerContext. Loggers are created under the lock of their parent logger, so loggers with different parents could be created at the same time and increments of the shared counter could be lost. As a result, LoggerContext.size() could return a value lower than the actual number of loggers. The counter is now an AtomicInteger. This issue was reported in issues/1038 by hcantunc. The fix was contributed in PR #1055 by seonwoo_jung.

• TimeBasedRollingPolicy now supports half-day periods. Date patterns with the AM/PM marker, for example %d{yyyy-MM-dd-a}, used to be detected as daily and rolled over only at midnight. They now roll over at both 00:00 and 12:00. This issue was reported in issues/976 by shakthifuture. The fix was contributed in PR #1051 by seonwoo_jung. See TimeBasedRollingPolicy.

• If org.jline.jansi.AnsiConsole cannot be found on the class path, JansiConsoleAppender now emits warnings that explain how to add org.jline:jansi-core and then writes to the plain console stream. See codes.html#missingJlineJansi.

• The unused ch.qos.logback.classic.util.LogbackMDCAdapterSimple class was removed. LogbackMDCAdapter remains the default MDC adapter.

• A bit-wise identical binary of this version can be reproduced by building from source code at commit 07d291ca0d280bc5da934ec9ff5f1da634fd7937 associated with the tag v_1.6.4. The release was built using Java "21" 2023-10-17 LTS build 21.0.1.+12-LTS-29 under Linux Debian 11.6.

Full Changelog: qos-ch/logback@v_1.6.3...v_1.6.4

Commits

• 07d291c preapre release 1.6.4
• 9627daf revert to Collections.unmodifiableMap instead of
• aa42fb5 disabled RollingCalendarTest#testVaryingNumberOfHalfDailyPeriods to shave off...
• ddc7459 Support HALF_DAY periodicity for AM/PM date patterns
• 42d75d7 disable LoggerContextTest#concurrentGetLoggerKeepsSizeConsistent to shave exe...
• bffd55e add warnings about missing jline.jansi classes
• 8de0b9b Fix data race on LoggerContext.size (#1038)
• 76c73d1 add MinimalUnmodifiableMap and return it in LogbackMDCAdapter#getPropertyMap
• a2c416a Fix formatting of email instruction in README
• 2c89727 mailing lists have been deactivated
• Additional commits viewable in compare view