Maven: Project Inheritance vs Project Aggregation

Reference URL: https://maven.apache.org/guides/introduction/introduction-to-the-pom.html#Project_Inheritance_vs_Project_Aggregation

Project Inheritance vs Project Aggregation

If you have several Maven projects, and they all have similar configurations, you can refactor your projects by pulling out those similar configurations and making a parent project. Thus, all you have to do is to let your Maven projects inherit that parent project, and those configurations would then be applied to all of them.

And if you have a group of projects that are built or processed together, you can create a parent project and have that parent project declare those projects as its modules. By doing so, you'd only have to build the parent and the rest will follow.

But of course, you can have both Project Inheritance and Project Aggregation. Meaning, you can have your modules specify a parent project, and at the same time, have that parent project specify those Maven projects as its modules. You'd just have to apply all three rules:

• Specify in every child POM who their parent POM is.
• Change the parent POMs packaging to the value "pom" .
• Specify in the parent POM the directories of its modules (children POMs)