Re: Rewrite of JAR plugin ready for merge

Hey, Martin.
I've checked it with our build in combination with 4.0.0-rc-6, and the
build fails. The master build of maven-jar-plugin (4.0.0-beta-2-SNAPSHOT)
is fine.
Some details:

mvn40 -v

Apache Maven 4.0.0-SNAPSHOT (477fe878ba0b8a7522cda992dd6b09192fae6e8e)

Maven home: /Users/sergey/Java/apache-maven-4.0.x-SNAPSHOT

Java version: 25.0.3, vendor: Amazon.com Inc., runtime:
/Users/sergey/.sdkman/candidates/java/25.0.3-amzn

Default locale: en_US, platform encoding: UTF-8, time zone: Europe/Amsterdam

OS name: "mac os x", version: "26.6.1", arch: "aarch64", family: "mac"

The build failure:


[ERROR] Failed to execute goal
org.apache.maven.plugins:maven-jar-plugin:4.0.0-beta-2-SNAPSHOT:jar
(default-jar) on project data-migration-impl-e2e-test: Error while
assembling the JAR file.:
/Users/username/dev/acme/server2/server/data-migration/data-migration-impl-e2e-test/target/classes-3197869813651266208
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to
execute goal org.apache.maven.plugins:maven-jar-plugin:4.0.0-beta-2-SNAPSHOT:jar
(default-jar) on project data-migration-impl-e2e-test: Error while
assembling the JAR file.
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute2(MojoExecutor.java:346)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute(MojoExecutor.java:310)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:214)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:179)
    at org.apache.maven.lifecycle.internal.MojoExecutor$1.run(MojoExecutor.java:168)
    at org.apache.maven.plugin.DefaultMojosExecutionStrategy.execute(DefaultMojosExecutionStrategy.java:39)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:165)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:110)
    at org.apache.maven.lifecycle.internal.builder.multithreaded.MultiThreadedBuilder.lambda$createBuildCallable$1(MultiThreadedBuilder.java:191)
    at java.util.concurrent.FutureTask.run(FutureTask.java:328)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:545)
    at java.util.concurrent.FutureTask.run(FutureTask.java:328)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1090)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:614)
    at java.lang.Thread.run(Thread.java:1474)
Caused by: org.apache.maven.api.plugin.MojoException: Error while
assembling the JAR file.
    at org.apache.maven.plugins.jar.AbstractJarMojo.execute(AbstractJarMojo.java:339)
    at org.apache.maven.plugin.DefaultBuildPluginManager$MojoWrapper.execute(DefaultBuildPluginManager.java:244)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute2(MojoExecutor.java:339)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute(MojoExecutor.java:310)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:214)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:179)
    at org.apache.maven.lifecycle.internal.MojoExecutor$1.run(MojoExecutor.java:168)
    at org.apache.maven.plugin.DefaultMojosExecutionStrategy.execute(DefaultMojosExecutionStrategy.java:39)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:165)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:110)
    at org.apache.maven.lifecycle.internal.builder.multithreaded.MultiThreadedBuilder.lambda$createBuildCallable$1(MultiThreadedBuilder.java:191)
    at java.util.concurrent.FutureTask.run(FutureTask.java:328)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:545)
    at java.util.concurrent.FutureTask.run(FutureTask.java:328)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1090)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:614)
    at java.lang.Thread.run(Thread.java:1474)
Caused by: java.nio.file.NoSuchFileException:
/Users/username/dev/acme/server2/server/data-migration/data-migration-impl-e2e-test/target/classes-3197869813651266208
    at sun.nio.fs.UnixException.translateToIOException(UnixException.java:92)
    at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:106)
    at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:111)
    at sun.nio.fs.UnixFileSystemProvider.createDirectory(UnixFileSystemProvider.java:418)
    at java.nio.file.Files.createDirectory(Files.java:647)
    at java.nio.file.TempFileHelper.create(TempFileHelper.java:130)
    at java.nio.file.TempFileHelper.createTempDirectory(TempFileHelper.java:162)
    at java.nio.file.Files.createTempDirectory(Files.java:893)
    at org.apache.maven.plugins.jar.MetadataFiles.baseDirectory(MetadataFiles.java:138)
    at org.apache.maven.plugins.jar.MetadataFiles.addManifest(MetadataFiles.java:122)
    at org.apache.maven.plugins.jar.ToolExecutor.writeSingleJAR(ToolExecutor.java:355)
    at org.apache.maven.plugins.jar.FileCollector.writeAllJARs(FileCollector.java:471)
    at org.apache.maven.plugins.jar.ToolExecutor.writeAllJARs(ToolExecutor.java:293)
    at org.apache.maven.plugins.jar.AbstractJarMojo.createArchives(AbstractJarMojo.java:322)
    at org.apache.maven.plugins.jar.AbstractJarMojo.execute(AbstractJarMojo.java:335)
    at org.apache.maven.plugin.DefaultBuildPluginManager$MojoWrapper.execute(DefaultBuildPluginManager.java:244)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute2(MojoExecutor.java:339)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute(MojoExecutor.java:310)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:214)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:179)
    at org.apache.maven.lifecycle.internal.MojoExecutor$1.run(MojoExecutor.java:168)
    at org.apache.maven.plugin.DefaultMojosExecutionStrategy.execute(DefaultMojosExecutionStrategy.java:39)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:165)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:110)
    at org.apache.maven.lifecycle.internal.builder.multithreaded.MultiThreadedBuilder.lambda$createBuildCallable$1(MultiThreadedBuilder.java:191)
    at java.util.concurrent.FutureTask.run(FutureTask.java:328)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:545)
    at java.util.concurrent.FutureTask.run(FutureTask.java:328)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1090)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:614)
    at java.lang.Thread.run(Thread.java:1474)



On Mon, Aug 17, 2026 at 10:32 AM Martin Desruisseaux via dev <
[email protected]> wrote:

> Hello all
>
> A pull request which rewrites the Maven JAR Plugin is ready for merge
> and already got some reviews:
>
>     https://github.com/apache/maven-jar-plugin/pull/508
>
> It has been discussed through some channels (GitHub, Slack). This email
> is for bringing attention via another channel in order to see if there
> is objection to the merge.
>
> The major insensitive for the rewrite was to support Java Modules Source
> Hierarchy. This is essential for continuing progress on the Java module
> support. Internally, the major change is that the new implementation
> uses the `jar` tool bundled in the JDK instead of our own Maven Archiver
> (except for generating the `MANIFEST.MF` content, where Maven Archiver
> is still used). It provides advantage such as safer multi-release JAR
> files and enable the use of more options in the future such as module
> hashes.
>
> If there is any comment or objection, please let us known. If none, I
> propose that we merge later this week.
>
> Thanks,
>
>      Martin
>
>