~~ under the License.

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 Maven configuration management
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 The Maven Team
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Configuration levels in maven

 In maven configuration control happens on four differ levels: the site level, the group level,
 the project level, and the user level. On the site level you can configure maven for all users

 *
 * The root locator is usually looked up from the plexus container.
 * One notable exception is the computation of the early {@code session.rootDirectory}
 * property which happens very early.  The implementation used in this case
 * will be discovered using the JDK service mechanism.
 *
 * The default implementation will look for a {@code .mvn} child directory

    /**
     * Sets the base directory of the current project.
     *
     * @param projectDirectory The base directory of the current project, may be {@code null} if profile activation
     *                         happens in the context of metadata retrieval rather than project building.
     * @return This context, never {@code null}.
     */
    public DefaultProfileActivationContext setProjectDirectory(Path projectDirectory) {

        /*

        This will not work until the RR plugin is released to get rid of the binding to the reporting exception which is a mistake.

        This happens after removing the reporting API from the core:

        java.lang.NoClassDefFoundError: org/apache/maven/reporting/MavenReportException

                if (!containsModule(moduleName, cache)) {
                    /*
                     * Not patching an existing module. This case should be unusual. If it nevertheless
                     * happens, add on class-path or module-path if allowed, or keep patching otherwise.
                     * The latter case (keep patching) is okay if the main module will be defined later.
                     */

            }

            pomArtifact = rel.pomArtifact;

            relocatedArtifact = rel.relocatedArtifact;

            if (rel.project == null) {
                // When this happens we have a Maven 1.x POM, or some invalid POM.
                // It should have never found its way into Maven 2.x repository but it did.
                dependencies = Collections.emptyList();
            } else {

   * known limitations are notably that:

     1. plugin goal execution in a child is usually simply appended (at end): you can't try to insert in the middle of pre-existing inherited executions,

     2. append happens at plugin level first, then goal level, independently from phases.
        This means for example that adding pluginA:goal2 to pre-existing (pluginA:goal1, pluginB:goal) will lead to (pluginA:goal1, pluginA:goal2, pluginB:goal)

                if (!containsModule(moduleName, cache)) {
                    /*
                     * Not patching an existing module. This case should be unusual. If it nevertheless
                     * happens, add on class-path or module-path if allowed, or keep patching otherwise.
                     * The latter case (keep patching) is okay if the main module will be defined later.
                     */

            }
            trace = trace.getParent();
        }
        return collectStepTrace;
    }

    /**
     * The event "artifact resolved" if fired WHENEVER an artifact is resolved, BUT it happens also when an artifact
     * descriptor (model, the POM) is being built, and parent (and parent of parent...) is being asked for. Hence, this

            Arrays.asList(ValidationReportLevel.INLINE, ValidationReportLevel.BRIEF));

    private enum ValidationReportLevel {
        NONE, // mute validation completely (validation issue collection still happens, it is just not reported!)
        INLINE, // inline, each "internal" problem one line next to mojo invocation
        SUMMARY, // at end, list of plugin GAVs along with ANY validation issues