Managing POM versions

This article won’t be long but could be a lifesaver. If you use Maven, how many times did you need to manually update POM versions in an entire modules hierarchy? For me, the answer is: “too many”.

When you project grows to include many Maven modules, releasing a new version can be a nightmare. Sure, you have the maven-release-plugin. It does many things under the cover but in some cases, I saw it fail. What do you do then? You manually change your POM version in your modules hierarchy:

• the version of the module’s POM
• the version of the parent’s POM

It’s not only a boring taks, it’s also an error-prone one. Imagine my surprise when I found the maven-version-plugin and its little jewel of a command line:

mvn versions:set -DnewVersion=1.0.1-SNAPSHOT

And presto, the plugin does it all for you, entering each module and changing the previous informations:

[INFO] [versions:set]
[INFO] Searching for local aggregator root...
[INFO] Local aggregation root: D:\workspace\Champion Utilities
[INFO] Processing ch.frankel.champions.license:license
[INFO]     Updating project ch.frankel.champions.license:license
[INFO]         from version 1.0.0 to 1.0.1-SNAPSHOT
[INFO]
[INFO] Processing ch.frankel.champions.license:license-check
[INFO]     Updating parent ch.frankel.champions.license:license
[INFO]         from version 1.0.0 to 1.0.1-SNAPSHOT
[INFO]     Updating project ch.frankel.champions.license:license-check
[INFO]         from version 1.0.0 to 1.0.1-SNAPSHOT
[INFO]
[INFO] Processing ch.frankel.champions.license:license-common
[INFO]     Updating parent ch.frankel.champions.license:license
[INFO]         from version 1.0.0 to 1.0.1-SNAPSHOT
[INFO]     Updating project ch.frankel.champions.license:license-common
[INFO]         from version 1.0.0 to 1.0.1-SNAPSHOT
[INFO]
[INFO] Processing ch.frankel.champions.license:license-generation
[INFO]     Updating parent ch.frankel.champions.license:license
[INFO]         from version 1.0.0 to 1.0.1-SNAPSHOT
[INFO]     Updating project ch.frankel.champions.license:license-generation
[INFO]         from version 1.0.0 to 1.0.1-SNAPSHOT

Give it a try, it’s a real powerful yet easy!

From http://blog.frankel.ch/managing-pom-versions