The Apache Maven team is pleased to announce the release of the Apache
Maven 3.6.1.

Apache Maven is a software project management and comprehension tool. Based
on the concept of a project object model (POM), Maven can manage a
project’s build, reporting and documentation from a central piece of
information.

You can find out more about Apache Maven at https://maven.apache.org

You can download the appropriate sources etc. from
the download page

We really value the contributions of these non committers, so this section is
focused on those individuals. Descriptions of the issues fixed can be found at
the end of these release notes.

Issue Reporters of this release:

MNG-5705 Ondra Žižka
MNG-5965 Matthias Schmalz
MNG-6059 Andreas Sewe
MNG-6159 Christian Aistleitner
MNG-6213 Jin Kwon
MNG-6256 Christoph Etzel
MNG-6261 Dawid Weiss
MNG-6262 Gene Smith
MNG-6346 Patrik Jetzer
MNG-6374 Rohan Padhye
MNG-6495 Elliotte Rusty Harold
MNG-6506 Andreas Veithen
MNG-6526 Olaf Otto
MNG-6529 Michael Istria
MNG-6530 Michael Istria
MNG-6533 Michael Istria
MNG-6543 Romain Manni-Bucau
MNG-6558 Guy Brand
MNG-6577 Rohan Padhye
MNG-6591 Olaf Otto
MNG-6605 Gunnar Wagenknecht
MNG-6618 Viacheslav Yakunin

Code Contributors of this release:

MNG-6374 Gabriel Belingueres (indirectly via plexus-utils PR)
MNG-6529 Michael Istria
MNG-6530 Michael Istria
MNG-6558 Guy Brand
MNG-6261 Fabiano C. de Oliveira
MNG-6533 Michael Istria

Many thanks to all reporters and contributors for their time and support.

(Please send an email to the dev list if we missed one to mention).

Preliminary Testers

Thanks to the following preliminary testers:

Gabriel Belingueres
Francois Papon
Eric Lilja

Known Issues

If you are using Maven reporting, it might happen that you will get an exception which looks like this:

[INFO] Scanning for projects...
[ERROR] Internal error: java.lang.NullPointerException -> [Help 1]
org.apache.maven.InternalErrorException: Internal error: java.lang.NullPointerException
    at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:120)
...
Caused by: java.lang.NullPointerException
    at org.apache.maven.model.plugin.DefaultReportingConverter.convert (DefaultReportingConverter.java:243)
...

This is caused by using a .. which does not contain
a element.

Temporarily this issue can circumvented by adding an empty element
inside the .

An issue has been created to track the fix.

Overview about the changes

An issue has been fixed causing multiple executions of plugin goals, related to
using parallel build options like mvn plugin:goal -T 4. This resulted in duplicated
executions of phases. This has been fixed with MNG-5965.
NullPointerException related to call in parallel build like mvn -T 1C clean javadoc:aggregate
MNG-5705
A performance issue related to artifact transfer has been found related to WAGON-537. It
has been solved via the update to Maven Wagon 3.3.1.
There had been issues related calling Maven script like this: mvn -f ..
- Having parentheses within the path, which has been fixed with MNG-6346.
- Script can break having special characters as part of the path, which has
  been solved with MNG-6256.
Issue related to the Maven Resolver API which broke some IDEs (for example https://youtrack.jetbrains.com/issue/IDEA-201282);
this has been fixed by MNG-6538.
Issue related to missing event for ToolchainsBuildingResult on EventSpy MNG-6558.
Issue related to support Java 9+ ClassLoader.findClass(String moduleName, String name) in Mojos.
This has been fixed with MNG-6543.
Improvement about the memory consumption has been done with MNG-6571.
Issue related to relative parent POM resolution failing in 3.5.0 with complex multimodule builds
has been fixed with MNG-6261.
Missing export for org.slf4j.event.Level has been done with MNG-6618

User visible Changes

Maven has now a an option to suppress the transfer progress when downloading/uploading
in interactive mode.

mvn --no-transfer-progress ....

or in short:

mvn -ntp ... ....

There had been an issues like MNG-6505 and MNG-6059 related to the construction of
URL’s etc. within distributionManagement and scm part in the pom for multi module
builds like this:

     child.scm.developerConnection.inherit.append.path="true"
     child.scm.url.inherit.append.path="true" />

Detailed explanations can be found in Inheritance Assembly and in MNG-6059

The detailed issue list

Bugs:

MNG-5705 – NPE on parallel build in BuilderCommon.handleBuildError(BuilderCommon.java:147)
MNG-5965 – Parallel build multiplies work if multiple goals are given
MNG-5995 – Maven itself cannot run without maven-compat
MNG-6256 – Maven script can break if “-f” path contains special characters
MNG-6261 – Relative parent POM resolution failing in 3.5.0 with complex multimodule builds
MNG-6262 – getCanonicalFile() is not used consistently during project resolution
MNG-6346 – … was unexpected at this time when using -f option and path contains brackets
MNG-6374 – ModelBuilder hangs with malformed pom.xml
MNG-6429 – Integration Test site publishing requires Java 7 (or javadoc errors ignored)
MNG-6495 – ModelResolver cannot be null
MNG-6505 – child.(x.y).inherit.append.path value should be inherited
MNG-6506 – Mojos are unable to load package annotations on Java >= 9
MNG-6529 – ProjectBuilder.build(List projects, boolean, ProjectBuildingRequest) doesn’t honor ProjectBuildingRequest.isResolveDependencies()
MNG-6530 – Regression in ProjectBuilder when file change between invocations (introduced by MNG-6311)
MNG-6533 – ProjectBuilder.build(list_of_projects,...) does not contain MavenProject in exception report
MNG-6543 – Upgrade plexus classworld to support java 9+ ClassLoader.findClass(String moduleName, String name) in Mojos
MNG-6558 – ToolchainsBuildingResult event is not sent on EventSpy
MNG-6577 – pom.xml: Uncaught IllegalArgumentException when parsing unicode entity ref
MNG-6590 – DefaultProjectArtifactsCache java.lang.IllegalStateException: Duplicate artifact resolution result
MNG-6599 – unknown version in model id when version is defined from parent

Improvements

MNG-6059 – Important use cases not covered, as child.inherit.append.path affects all children
MNG-6159 – Child path adjustments break git scm urls
MNG-6213 – Maven doesn’t check the validity of scope value
MNG-6481 – Allow to compile and test Maven with Java 11
MNG-6513 – Replace depreated Plexus javadoc tags with annotations in ITs
MNG-6515 – Fix javadoc build errors under Java 8 and 11
MNG-6520 – Update assembly descriptors to 2.0.0
MNG-6522 – Prepare Maven’s Core Integration Test Suite to test with Java 12 and 13-ea
MNG-6572 – use int or long instead of BigIntegers for little numbers in ComparableVersion
MNG-6593 – track input location for super-pom
MNG-6597 – add input location tracking for plugins configuration
MNG-6600 – add input location tracking for default lifecycle bindings executions
MNG-6601 – add input location tracking for site’s reportPlugins injected by reports conversion
MNG-6605 – Allow to suppress download messages in interactive mode
MNG-6611 – Update animal-sniffer-maven-plugin to 1.17

Wish

MNG-6571 – Maven memory consumption issue

Task

MNG-6538 – Upgrade Maven Artifact Resolver to 1.3.3 to restore API
MNG-6544 – Replace CacheUtils#{eq,hash} with Objects
MNG-6573 – Use latest Maven 3.6.0 to build Maven Core and plugins with ASF CI
MNG-6618 – Maven doesn’t export org.slf4j.event.Level

Dependency upgrade

MNG-6526 – Upgrade to Wagon 3.3.1 (from 3.2.0)
MNG-6591 – Upgrade to Wagon 3.3.2

The full list of changes can be found in our issue management system.

Complete Release Notes

See complete release notes for all versions

The Apache Maven Team.