[MWRAPPER-113] Error and warning output goes to standard output and intermingles with Maven output

• Type: Bug
• Status: Closed
• Priority: Trivial
• Resolution: Fixed
• Affects Version/s: 3.2.0, 3.3.0
• Fix Version/s: 3.3.0
• Component/s: Maven Wrapper Scripts
• Labels: pull-request-available
• Flags: Patch
• Assignee: Benjamin Marwell
• Reporter: Ingo Karkat
• Created: 27/Jul/23 09:08
• Updated: 17/Apr/24 09:11
• Resolved: 09/Feb/24 14:53

Description

Errors and warnings from the wrapper should go to standard error, so that those are also shown to the user when the regular Maven output is suppressed, redirected into a file, or captured by a script.
For the latter use case, separation is especially critical because otherwise error output is mistakenly interpreted as desired Maven output (for example, when obtaining the list of Maven project names in the reactor with mvnw --quiet -Dexec.executable=echo '-Dexec.args=${project.groupId}:${project.artifactId}' org.codehaus.mojo:exec-maven-plugin:exec).
The current wrapper scripts do this only inconsistently, and so warnings like Warning: JAVA_HOME environment variable is not set. are printed to stdout instead of stderr.

Pull request: https://github.com/apache/maven-wrapper/pull/106

Issue Links

• links to: GitHub Pull Request #106