Skip to content

[4.0.x] Fix mvn.cmd jvm.config read failing silently on Windows CI #12379

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
gnodet merged 1 commit into from
Jun 27, 2026
+25 −4
Merged

[4.0.x] Fix mvn.cmd jvm.config read failing silently on Windows CI #12379

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
29 changes: 25 additions & 4 deletions apache-maven/src/assembly/maven/bin/mvn.cmd
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -184,7 +184,20 @@ if not exist "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadJvmConfig

rem Use Java source-launch mode (JDK 11+) to parse jvm.config
rem This avoids batch script parsing issues with special characters (pipes, quotes, @, etc.)
rem Use temp file approach with cmd /c to ensure proper file handle release
rem Java writes parsed output to a temp file; we read it with 'set /p' + input redirect.
rem
rem Why 'set /p <file' instead of 'for /f ... in (file)':
rem - 'for /f' silently produces no output when the file is briefly locked
rem (e.g. by Windows Defender real-time scanning), leaving JVM_CONFIG_MAVEN_OPTS empty
rem and causing hard-to-diagnose Maven startup failures.
rem - 'set /p <file' uses a transient input-redirect open with different sharing flags,
rem making it far less susceptible to lock contention. If the file IS locked, it
rem emits a visible error to stderr rather than failing silently.
rem
rem Why not capture stdout directly ('for /f ... in (`command`)')?
rem - cmd.exe's child shell interprets special characters (pipes |, ampersands &, etc.)
rem in the captured output, which breaks jvm.config values like
rem -Dhttp.nonProxyHosts=de|*.de (the core use case for JvmConfigParser).

set "JVM_CONFIG_TEMP=%TEMP%\mvn-jvm-config-%RANDOM%-%RANDOM%.txt"

Expand All @@ -196,7 +209,7 @@ if defined MAVEN_DEBUG_SCRIPT (
echo [DEBUG] Parser arguments: "%MAVEN_HOME%\bin\JvmConfigParser.java" "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" "%MAVEN_PROJECTBASEDIR%" "%JVM_CONFIG_TEMP%"
)

rem Run parser with output file as third argument - Java writes directly to file to avoid Windows file locking issues
rem Run parser with output file as third argument - Java writes directly to file
"%JAVACMD%" "%MAVEN_HOME%\bin\JvmConfigParser.java" "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" "%MAVEN_PROJECTBASEDIR%" "%JVM_CONFIG_TEMP%"
set JVM_CONFIG_EXIT=%ERRORLEVEL%

Expand All @@ -215,13 +228,21 @@ if %JVM_CONFIG_EXIT% neq 0 (
exit /b 1
)

rem Read the output file
rem Read the output file using 'set /p' with input redirect (see comment above)
if exist "%JVM_CONFIG_TEMP%" (
if defined MAVEN_DEBUG_SCRIPT (
echo [DEBUG] Temp file contents:
type "%JVM_CONFIG_TEMP%"
)
for /f "usebackq tokens=*" %%i in ("%JVM_CONFIG_TEMP%") do set "JVM_CONFIG_MAVEN_OPTS=%%i"
set /p JVM_CONFIG_MAVEN_OPTS=<"%JVM_CONFIG_TEMP%" 2>nul
rem Retry once after a brief delay if the read failed (Windows Defender file lock)
if not defined JVM_CONFIG_MAVEN_OPTS (
if defined MAVEN_DEBUG_SCRIPT (
echo [DEBUG] First read returned empty, retrying after delay...
)
ping -n 2 127.0.0.1 >nul 2>nul
set /p JVM_CONFIG_MAVEN_OPTS=<"%JVM_CONFIG_TEMP%" 2>nul
)
del "%JVM_CONFIG_TEMP%" 2>nul
)

Expand Down
Loading