Maven cheat sheet (0.44.2)

There is an updated version of this post.

This is a list of useful Maven commands. They work with Novelang-0.44.2. Later version will probably make some of them less verbose, using some default parameters.

Convention: the Novelang/$ represents the command prompt, with working directory being Novelang’s home directory. Subdirectories appear when needed.

Plugin versions

Stay up-to-date by listing more recent plugins (there is another goal for dependencies):

Novelang/$ mvn versions:display-plugin-updates

Show dependency tree:

Novelang/$ mvn dependency:tree

Feed local repository with fresh artifacts

Novelang/$ mvn clean install 

Force child modules version

Force the version of every child module to the one of the parent:

Novelang/$ mvn -N versions:update-child-modules

Performing a release (may be specific to Novelang-0.44.2)

First, clean previous POM backup files:

Novelang/$ mvn release:clean

Then prepare the release. This does the following:

• Check VCS state. Includes: no uncommitted file; remote repository sync’ed with local.
  
• Change the POM versions to release version (shown as M.m.f in the snippet below).
  
• Run the build, using declared .
  
• Commit changed POMs to local SCM.
  
• Tag the SCM locally.
  
• Pushes the changes on remote repository, including tags (failing on a conflict).
  
• Revert SCM versions to development version.
  

Novelang/$ mvn -e --batch-mode release:prepare -Drelease=false -DlocalCheckout=true -DreleaseVersion=M.m.f -DdevelopmentVersion=SNAPSHOT -Dtag=release-M.m.f > build-release-prepare.log

This part is likely to fail. If something goes wrong:

• Reset git in the --hard way, to the version immediately before Maven’s changes.
  
• Delete release-M.m.f tag local git repository.
  
• Delete release-M.m.f tag on remote git repository: git push -v github :refs/tags/release-M.m.f
  
• Force synchronization between local git repository and remote one. This may be done by committing an innocuous change, then pushing it with --force option (better idea, anyone?).
  
• Call again: Novelang/$ mvn release:cleanGet sure that’s everything OK with gitk.
  

Might be useful to reset all POM version (like after some POM or branch hacking): set root pom.xml version to SNAPSHOT and run mvn versions:update-child-modules.

Once this is done, our git repositories contain good, tagged stuff. Last step is to perform the final build.

Novelang/$ mvn release:perform > build-release-perform.log

(There is no additional parameter to pass; the release.prepare did create some POM copies with relevant information.)

The release.perform goal performs a fresh checkout in Novelang/target/checkout where all the pom.xml contain expected M.m.f version. The build calls the deploy:deploy on Novelang-documentation and Novelang-distribution which upload relevant files on SourceForge and send email notifications.

Useful links

Using master password.

Mini-guide about Maven release plugin.

Untested

Resume from a give module folder instead of restarting the build since the beginning:

Novelang/$ mvn reactor:resume -Dfrom=bar