Slides of the session "Apache Maven 4.0.0 - The Future" of the online event JCON 2022 on 20. September.

1. Blog: blog.soebes.io
Twitter: @khmarbaise
Email: maven4@soebes.de
Dipl.Ing.(FH) Karl Heinz Marbaise
Apache Maven 4.0.0
–
The Future

2. www.soebes.com 2
About me
●
Apache Maven Committer
– since Dec. 2013
●
Apache Maven PMC Member
– since August 2014
●
Apache Software Foundation Member
– since April 2017
●
Apache Maven Project Chairman
– Since April 2022

3. www.soebes.com 3
Agenda
●
Apache Maven Ecosystem
●
Maven Ecosystem
●
Architecture
●
Consumer/Build POM
●
Timeline
●
JDK Requirement
●
Questions

4. www.soebes.com 5
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer

5. www.soebes.com 6
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer
• Core: clean, compiler, resources, install,
deploy, surefire, …
• Packaging: jar, war, shade, source, jlink,
jmod, …
• Reporting: site, javadoc, jxr, pmd, jdeps,
checkstyl, ...
• Tools: archetype, assembly, enforcer,
dependency, …

6. www.soebes.com 7
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent
POMs
Archetypes
Indexer
• ASF Maven Parent
• Maven Parent
• Maven Plugin Parent
• Maven Shared Parent
• Maven Skins Parent
• Apache Resource Bundle

7. www.soebes.com 8
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer
• maven-archiver
• maven-invoker
• maven-filtering
• maven-dependency-analyzer
• maven-artifact-transfer
• maven-jarsigner
• maven-shared-utils
• maven-shared-io
• ...

8. www.soebes.com 9
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer
• Doxia Core
• Doxia Site Tools
• Doxia Modules
● apt, xdoc, markdown,FML, …
• ...

9. www.soebes.com 10
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer
• Maven Default Skin
• Maven Fluido Skin
• Maven Application Skin
• Maven Classic Skin
• Maven Stylus Skin

10. www.soebes.com 11
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer
• maven-archetype-j2ee-simple
• maven-archetype-plugin
• maven-archetype-quickstart
• ...

11. www.soebes.com 12
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer
• aka Eclipse Aether (2016)
http://incubator.apache.org/ip-
clearance/maven-aether.html

12. www.soebes.com 13
Apache Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer

13. www.soebes.com 14
Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer
Plexus Components (~13) MojoHaus Plugins (~80)
• https://github.com/codehaus-plexus
https://github.com/codehaus-plexus
● plexus-classworlds
● plexus-modello
● plexus-utils
● plexus-archiver
● plexus-io
● plexus-languages
● Plexus-interpolation
...

14. www.soebes.com 15
Maven Ecosystem
Maven Plugins (~50)
Maven
Core Core
ITs
Artifact Resolver
Maven Shared Components (~25)
Doxia
Skins
Parent POMs
Archetypes
Indexer
Plexus Components (~13) MojoHaus Plugins (~80)
• https://github.com/mojohaus/
https://github.com/mojohaus/
● mrm-maven-plugin
● versions-maven-plugin
● build-helper-maven-plugin
● buildnumber-maven-plugin
● animal-sniffer-maven-plugin
● appassembler-maven-plugin
● jaxb2-maven-plugin
● flatten-maven-plugin
● exec-maven-plugin
● rpm-maven-plugin
● templating-maven-plugin
● ...

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Architecture
Maven 2 - 2005

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Architecture
Maven 3 - 2010

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Architecture
Maven 3.5+ - 2017

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Architecture
Maven 4.X - 2020/2021/2022

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Consumer / Build POM
POM V4
●
Maven 1 started with the story
modelVersion 3.0.0
●
Maven 2/3 has continued the story with
modelVersion 4.0.0
<project ...>
<modelVersion>4.0.0</modelVersion>
…
</project>

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Consumer / Build POM
POM V4
●
The pom declarares the following
information:
●
dependencies, dependencyManagement
●
plugins, pluginManagement
●
profiles, repositories
●
build, reporting
●
distributionManagement
●
etc.

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Consumer / Build POM
POM V4
●
The function of a POM:
1.Serves as declarative description of
the build process for a project.
2.Serves as a description of the project
dependency graph.

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Consumer / Build POM
POM V4
●
Changing the POM format?
– The POM is consumed by:
●
Apache BuildR, Gradle, Apache Ivy, sbt
●
by IDE's
●
and many other tools
– as a description of dependencies.

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Consumer / Build POM
POM V4
●
Requirements to change the POM
format:
– All tools would needed to be changed.
– We have to fork
fork Central Repository.

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Consumer / Build POM
POM V4
●
Requirements to change the POM
format:
– All tools would needed to be changed.
– We have to fork
fork Central Repository.

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Consumer / Build POM
POM V5
Build
Information
POM V5+ POM V4
Consumer POM
Central Repository
Build POM
Project Dependency Tree (PDT)

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Consumer / Build POM
POM V4
●
POM V4 a.k.a. Consumer POM
Consumer POM
– Contains only dependencies (+
dependencyManagement)
– Remove all properties / build / modules
/ parent / ….
– See flatten-maven-plugin
●
https://cwiki.apache.org/confluence/display/MAVEN/Build+vs+Consumer+POM

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DEMO

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POM V5 → Maven 5.X
●
Core must be able to read:
– POM V4
– POM V5
●
Core must be able to produce POM V4

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Timeline
●
Maven 4
– Build/Consumer POM
– Reactor Improvements
●
Maven 3.X/4.X
– Maven Wrapper
– Maven Daemon
●
https://cwiki.apache.org/confluence/display/MAVEN/Build+vs+Consumer+POM

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Minimum JDK Runtime
Requirements
●
Twitter Poll
– 1,841 Votes
●
JDK 8 – 16.1 %
●
JDK 11 – 36.9 %
●
JDK 17 – 43 %
●
Version available at time GA – 4 %
●
https://twitter.com/khmarbaise/status/1549429653202518016

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Minimum JDK Runtime
Requirements
●
LinkedIn Poll
– 3,717 Votes
●
JDK 8 – 56 %
●
JDK 11 – 27 %
●
JDK 17 – 13 %
●
Version available at time GA – 5 %
●
https://www.linkedin.com/feed/update/urn:li:activity:6955432897084325889

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Minimum JDK Runtime
Requirements
●
Maven 3.8.X
– JDK 7
●
Maven 3.9.X (NOT YET!)
– JDK 8
●
Maven 4.X (NOT YET!)
– actually 8 maybe we change to JDK 11
or even on JDK17; Not sure yet!
https://maven.apache.org/docs/history.html

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maven4@soebes.com
Thank you for your attention.
Questions?