How to create an empty multi module Maven project?

The easiest way I’ve found to do this is to use the pom-root archetype to create the top-level pom and then repeatedly use archetype:generate to create each module individually. This will automatically add the modules to the root pom (aggregator) and set the root pom as the parent pom for each module (edit: apparently some archetypes can have a hard-coded parent, but it works for maven-archetype-quickstart).

Here’s the breakdown:

1. Create the top-level root:

   mvn archetype:generate \
   -DarchetypeGroupId=org.codehaus.mojo.archetypes \
   -DarchetypeArtifactId=pom-root \
   -DarchetypeVersion=RELEASE
   

2. cd into your newly created root dir.

3. For each module:

   mvn archetype:generate \
   -DarchetypeGroupId=org.apache.maven.archetypes \
   -DarchetypeArtifactId=maven-archetype-quickstart \
   -DarchetypeVersion=RELEASE
   

Note that -DarchetypeVersion=RELEASE above will automatically use the latest version of the archetype. You may want to add -DgroupId=... to each of those commands to avoid repeating yourself.