This release improves javac --release version handling and updates the Error Prone compiler integration for recent JDKs:

• Normalize 1.x release versions for javac (#516): While -source and -target accept both 1.8 and 8, javac --release rejects 1.x spellings (release version 1.8 not supported). JavacCompiler now maps 1.5–1.8 to 5–8 automatically so projects can derive <release> from an existing 1.x target property without failure.
• Error Prone 2.50.0 & JDK 27 compatibility (#517): Upgrades plexus-compiler-javac-errorprone to Error Prone 2.50.0 (fixing JCCompilationUnit.endPositions removal on JDK 27, JDK-8372948). Because Error Prone 2.43+ requires a Java 21 runtime, the plexus-compiler-javac-errorprone module now requires Java 21 (all other compiler modules remain on Java 8).
• Test harness JDK version detection (#518): AbstractCompilerTest now derives the running Java feature version dynamically via getJavaFeatureVersion() instead of matching a fixed list of known JDK versions, fixing test execution on JDK 26+.

🚨 Removed

• Bump Error Prone to 2.50.0, requires Java 21 (#517) @slachiewicz

🚀 New features and improvements

• Accept the 1.x spelling for the javac release version (#516) @slachiewicz

📝 Documentation updates

• Drop the Source Xref menu item (#519) @slachiewicz

👻 Maintenance

• Use JUnit 5 in the AspectJ compiler IT (#531) @slachiewicz
• Remove redundant javaVersion property (#530) @slachiewicz
• Drop the Source Xref menu item (#519) @slachiewicz
• Derive test expectations from the JDK feature version (#518) @slachiewicz

🔧 Build

• Allow running the release drafter by hand (#526) @slachiewicz
• Keep Dependabot off plexus-xml 4.x and SLF4J 2.x (#522) @slachiewicz

📦 Dependency updates

• Bump com.google.guava:guava from 33.7.1-jre to 33.8.0-jre (#525, #532) @dependabot[bot]
• Bump eclipse.sisu.version from 1.1.0 to 1.1.1 (#527) @dependabot[bot]
• Bump org.apache.commons:commons-lang3 from 3.20.0 to 3.21.0 (#523) @dependabot[bot]
• Bump Error Prone to 2.50.0, requires Java 21 (#517) @slachiewicz

Full changelog

🐛 Bug Fixes

• Restore the -Xlint category on in-process javac warnings (#515) @slachiewicz
• Skip blank annotation processor names in javac and eclipse (#513) @slachiewicz
• Fix aspectj-compiler IT for Maven 4 stdout prefixing (#509) @ascheman

📝 Documentation updates

• Stop pinning a version in the README snippet (#507) @slachiewicz

🔧 Build

• Point the SCM URLs at HTTPS (#506) @slachiewicz
• Draft the version the labels imply, not always a patch (#505) @slachiewicz

📦 Dependency updates

• Bump org.eclipse.jdt:ecj from 3.46.0 to 3.46.100 (#514) @dependabot[bot]
• Bump com.google.guava:guava from 33.6.0-jre to 33.7.1-jre (#511) @dependabot[bot]

javac diagnostics come through more faithfully in this release: multi-line notes are forwarded rather
than swallowed, warnings are counted by kind instead of by subtraction, output no classifier recognised
is now reported instead of dropped, and a forked javac no longer reports the diagnostic column one off.
Argument files are quoted (#484). The modules also declare automatic module names, and the compiler now
depends on the resolver directly rather than on maven-core. That is why this is 2.17.0 and not 2.16.3.

🚀 New features and improvements

• Establish automatic module names (#492) @slachiewicz
• Quote javac argument files (#484) @wilx

🐛 Bug Fixes

• Forward javac notes, including the multi-line ones (#496) @slachiewicz
• Report javac output that no classifier recognised (#494) @slachiewicz
• Fix off by one column in diagnostic when using "forked" execution of javac. (#483) @wilx

👻 Maintenance

• Bump remoting in the MCOMPILER-346 reproducer (#501) @slachiewicz
• Remove the Maven and commons-lang dependencies from the compiler TCK (#499) @slachiewicz
• Depend on the resolver directly instead of maven-core (#498) @slachiewicz
• Count warnings by kind, not by subtraction (#497) @slachiewicz
• Drop two properties the build does not need (#495) @slachiewicz
• Drop the managed plexus-component-annotations entry (#493) @slachiewicz
• Rewrite README with usage, status and version guidance (#491) @slachiewicz
• Restore the document metadata dropped when the page was ported (#489) @slachiewicz
• Format the converted site page to the project's spotless rules (#488) @slachiewicz
• Port the site documentation from APT to Markdown (#487) @slachiewicz
• Remove Hamcrest dependency and replace with JUnit assertions (#477) @slachiewicz

🔧 Build

• Update parent to plexus 27 (#502) @slachiewicz

📦 Dependency updates

🐛 Bug Fixes

• Fixed ConcurrentModificationException on compilerArguments (#466) @slachiewicz

📦 Dependency updates

• Bump org.codehaus.plexus:plexus from 24 to 25 (#468) @dependabot[bot]
• Bump org.codehaus.plexus:plexus-testing from 2.0.2 to 2.1.0 (#469) @dependabot[bot]
• Bump actions/checkout from 4 to 6 (#467) @dependabot[bot]
• Bump org.eclipse.jdt:ecj from 3.43.0 to 3.44.0 (#465) @dependabot[bot]
• Bump org.codehaus.plexus:plexus-testing from 2.0.1 to 2.0.2 (#464) @dependabot[bot]

🐛 Bug Fixes

• Fix detecting java version for JDK 1.8 (#462) @slawekjaranowski
• #420: fix detection of java version when JAVA_TOOL_OPTIONS is set (#426) @glhez

📦 Dependency updates

• Bump actions/checkout from 5 to 6 (#463) @dependabot[bot]

🚀 New features and improvements

• Added 3 MSVC csharp compiler options (#436) @MarcMazas
• Bump ErrorProne to 2.37.0 - requires Java 17 (#432) @slachiewicz

🐛 Bug Fixes

• Fix Zip Slip vulnerability in JAR extraction (#453) @copilot-swe-agent[bot]
• Fixed wrong excludes management (#444) @pzygielo

👻 Maintenance

• Replace FileUtils.deleteDirectory(File) with JDK provided API (#461) @slachiewicz
• chore: remove junit3 references (#458) @sparsick
• Update Java version checks to include JDK 25 (#452) @slachiewicz
• Include JDK 24 in CI (#433) @slachiewicz
• Apply spotless re-formatting (#429) @ascheman
• Create codeql.yml (#402) @slachiewicz
• Pass tests with Java 22 and 23 (#401) @slachiewicz

📦 Dependency updates

• Bump ErrorProne to 2.37.0 - requires Java 17 (#432) @slachiewicz
• Bump com.google.guava:guava to 33.5.0-jre (#449) @dependabot[bot]
• Bump eclipse.sisu.version from 0.9.0.M3 to 0.9.0.M4 (#438) @dependabot[bot]
• Bump org.codehaus.plexus:plexus to 24 (#456) @dependabot[bot]
• Bump org.codehaus.plexus:plexus-testing to 2.0.1 (#460) @dependabot[bot]
• Bump org.codehaus.plexus:plexus-utils to 4.0.2 (#414) @dependabot[bot]
• Bump org.codehaus.plexus:plexus-xml from 3.0.0 to 3.0.1 (#387) @dependabot[bot]
• Bump org.eclipse.jdt:ecj to 3.43.0 (#448) @dependabot[bot]
• Bump org.hamcrest:hamcrest from 2.2 to 3.0 (#399) @dependabot[bot]

🚀 New features and improvements

• Allow to override useUnsharedTable compiler argument (#373) @slawekjaranowski
• Lazy providers and better error reporting (#361) @kriegaex
• Only use "-release" parameter with javac 9+ (#362) @kwin
• Correctly determine the version of the underlying javac tool (#357) @kwin
• Use a TreeSet instead of HashSet to get consistent ordering of results (#352) @laeubi

🐛 Bug Fixes

• Cleanup dependencies (#369) @slachiewicz
• Path.relativize() may throw exception if source and build directories are on different Windows drives (#368) @slachiewicz
• Fix ECJ not using annotation processor when defined via processorpath (#350) @famod
• Report "Error occurred during initialization of VM" as error (#343) @olamy

📦 Dependency updates

• Bump org.codehaus.plexus:plexus from 16 to 17 (#372) @dependabot
• Bump com.google.errorprone:error_prone_core from 2.24.1 to 2.25.0 (#367) @dependabot
• Require Maven 3.6.3+ (#353) @slachiewicz
• Bump com.google.errorprone:error_prone_core from 2.24.0 to 2.24.1 (#348) @dependabot
• Bump org.apache.maven.plugins:maven-compiler-plugin from 3.12.0 to 3.12.1 (#345) @dependabot
• Bump com.google.errorprone:error_prone_core from 2.23.0 to 2.24.0 (#341) @dependabot
• Bump org.codehaus.plexus:plexus-component-annotations from 2.1.1 to 2.2.0 (#344) @dependabot

👻 Maintenance

• Bump project version to 2.15.0-SNAPSHOT (#370) @slawekjaranowski
• Use LocalRepositoryManager for resolving artifacts paths in tests (#366) @slawekjaranowski

🐛 Bug Fixes

• Return empty list for not existing source root location (#338) @slawekjaranowski
• Improve javac error output parsing - Fix #336 (#337) @kriegaex

📦 Dependency updates

• Bump org.apache.maven.plugins:maven-compiler-plugin from 3.11.0 to 3.12.0 (#339) @dependabot
• Bump com.google.guava:guava from 32.1.3-jre to 33.0.0-jre (#340) @dependabot
• Bump org.codehaus.plexus:plexus-testing from 1.2.0 to 1.3.0 (#335) @dependabot

🐛 Bug Fixes

• Restore AbstractCompiler#getLogger() method (#334) @slawekjaranowski

❗ Requirements for plexus compilers

• plexus-compiler-aspectj - JDK 17+, Maven 3.9.6
• plexus-compiler-eclipse - JDK 17+, Maven 3.9.6
• plexus-compiler-javac - JDK 8+
• plexus-compiler-javac-errorprone - JDK 11+

🚨 Removed

• Drop J2ObjC compiler (#325) @slawekjaranowski

🚀 New features and improvements

• Update AspectJ Compiler to 1.9.21 to support Java 21 (#330) @slachiewicz
• Require JDK 17 for build (#327) @slawekjaranowski
• Improve locking on JavacCompiler (#315) @gnodet
• Include 'parameter' and 'preview' describe log (#319) @jorsol
• Switch to SISU annotations and plugin, fixes #217 (#313) @gnodet
• Support jdk 21 (#311) @gnodet
• Require Maven 3.5.4+ (#283) @slachiewicz
• Require Java 11 for plexus-compiler-eclipse an javac-errorprone and aspectj compilers (#279) @slachiewicz
• Add support to run its with Java 20 (#277) @slachiewicz

🐛 Bug Fixes

• Fix javac memory leak (#309) @gnodet
• Validate zip file names before extracting (Zip Slip) (#291) @slachiewicz

📦 Dependency updates

• Update AspectJ Compiler to 1.9.21 to support Java 21 (#330) @slachiewicz
• Bump org.codehaus.plexus:plexus from 15 to 16 (#328) @dependabot
• Bump org.eclipse.jdt:ecj from 3.33.0 to 3.36.0 (#326) @dependabot
• Bump org.codehaus.plexus:plexus-testing from 1.1.0 to 1.2.0 (#317) @dependabot
• Bump org.junit:junit-bom from 5.10.0 to 5.10.1 (#320) @dependabot
• Bump org.apache.maven.plugins:maven-surefire-plugin from 3.2.1 to 3.2.2 (#321) @dependabot
• Upgrade parent and reformat using spotless (#314) @gnodet
• Bump org.apache.maven.plugins:maven-surefire-plugin from 3.1.2 to 3.2.1 (#310) @dependabot
• Bump com.google.errorprone:error_prone_core from 2.22.0 to 2.23.0 (#308) @dependabot
• Bump com.google.errorprone:error_prone_core from 2.21.1 to 2.22.0 (#306) @dependabot
• Bump org.apache.maven.plugins:maven-enforcer-plugin from 3.4.0 to 3.4.1 (#304) @dependabot
• Bump maven-surefire-plugin from 3.1.0 to 3.1.2 (#290) @dependabot
• Bump org.apache.maven.plugins:maven-enforcer-plugin from 3.3.0 to 3.4.0 (#301) @dependabot
• Bump com.google.errorprone:error_prone_core from 2.21.0 to 2.21.1 (#300) @dependabot
• Bump com.google.errorprone:error_prone_core from 2.20.0 to 2.21.0 (#299) @dependabot
• Bump org.junit:junit-bom from 5.9.3 to 5.10.0 (#298) @dependabot
• Bump error_prone_core from 2.19.1 to 2.20.0 (#295) @dependabot
• Bump maven-invoker-plugin from 3.5.1 to 3.6.0 (#294) @dependabot
• Bump extra-enforcer-rules from 1.6.2 to 1.7.0 (#289) @dependabot
• Bump maven-surefire-plugin from 3.0.0 to 3.1.0 (#284) @dependabot
• Bump error_prone_core from 2.18.0 to 2.19.1 (#286) @dependabot
• Bump junit-bom from 5.9.2 to 5.9.3 (#282) @dependabot
• Bump extra-enforcer-rules from 1.6.1 to 1.6.2 (#281) @dependabot
• Bump maven-invoker-plugin from 3.3.0 to 3.5.1 (#274) @dependabot
• Bump maven-enforcer-plugin from 3.2.1 to 3.3.0 (#276) @dependabot
• Bump animal-sniffer-maven-plugin from 1.22 to 1.23 (#273) @dependabot
• Bump groovy.version from 3.0.14 to 3.0.16 (#269) @dependabot
• Bump maven-compiler-plugin from 3.10.1 to 3.11.0 (#270) @dependabot
• Bump maven-surefire-plugin from 3.0.0-M8 to 3.0.0 (#271) @dependabot
• Bump maven-enforcer-plugin from 3.1.0 to 3.2.1 (#264) @dependabot
• Bump error_prone_core from 2.16 to 2.18.0 (#261) @dependabot
• Bump junit-bom from 5.9.1 to 5.9.2 (#262) @dependabot
• Bump maven-surefire-plugin from 3.0.0-M7 to 3.0.0-M8 (#263) @dependabot
• Bump groovy from 3.0.13 to 3.0.14 (#259) @slachiewicz
• Bump error_prone_core from 2.15.0 to 2.16 (#246) @dependabot

👻 Maintenance

• Bump project version to 2.14.0-SNAPSHOT (#331) @slawekjaranowski
• Document a requirements for plexus compilers (#329) @slawekjaranowski
• Reuse plexus-pom action for CI (#324) @slachiewicz
• Upgrade parent and reformat using spotless (#314) @gnodet
• JavacCompiler.java had a space in the wrong place (#303) @rzwitserloot
• Bump maven-surefire-plugin from 3.1.0 to 3.1.2 (#290) @dependabot
• Bump com.google.errorprone:error_prone_core from 2.20.0 to 2.21.0 (#299) @dependabot
• Bump maven-invoker-plugin from 3.5.1 to 3.6.0 (#294) @dependabot
• Bump maven-surefire-plugin from 3.0.0 to 3.1.0 (#284) @dependabot
• Bump error_prone_core from 2.18.0 to 2.19.1 (#286) @dependabot
• simplify compiler configuration (#280) @olamy

🔧 Build

• Add dependency to plexus-compiler-eclipse in ITs (#318) @slawekjaranowski