Commandline inheritance

The concept of inheritance of from generic to specific, where the more specific overrides the values of its ancestors.

In general, we see three levels, also described at Maven – Guide to Configuring Maven (apache.org): it uses the terms user, installation, project

Just to give a hint: when you're working with multiple Maven installations on your system, they all share "user" configuration. Think of server credentials, you don't want to specify these per installation.

Looking at the settings and toolchains there's something odd with the name of the flags: --global-x is AFTER --x. This is an inconsistency as nothing should be more global than "global".

I see a couple of options how to solve this:

1.  Switch the flags. This breaks compatibility in 2 ways: The flag overrides a different file and --settings will now override --global-settings.

2. Preserve user, and fix everything around it. This means that IF you use --global-settings, it's the new base. It can be overridden with user settings, which can be overridden with installation settings (maybe we don't need --maven-settings).

3.  Deprecate --global-settings and replace it with --maven-settings

4.  Rename the flags and use the terms from the configuration-page

5.  Drop flags for replacing existing settings, and use --settings as the one overriding the merge result of user+installation

6. Switch installation and user, so installation becomes global and can be overridden by user.

7.  Drop flags for replacing existing settings, and use --settings as the one overriding the merge result of installation + user (these will be switched!)