*
 * h3. plugins should be able to have specific metadata for a plugin model and that be translated -
 * dependencies - resources - configuration - extension points of plugins
 *
 * For a particular application plugin there will be a declarative descriptor for that plugin type.
 *
 * - nexus - the plugin class - UI to contribute - what JS to hook into the UI - what resources to

 maven 1.x and 2.x is that all project parameterization occurs in the POM and not from properties
 files.

 For many of the more advanced features in Maven2 it is critical that POMs be available in the local repository.
 Features like transitive dependencies and the new parent specification mechanism. The problem we run into is

    MavenExecutionResult setDependencyResolutionResult(DependencyResolutionResult result);

    DependencyResolutionResult getDependencyResolutionResult();

    // for each exception
    // - knowing what artifacts are missing
    // - project building exception
    // - invalid project model exception: list of markers
    // - xmlpull parser exception
    List<Throwable> getExceptions();

import org.apache.maven.execution.MavenSession;

/**
 * Allows core extensions to participate in Maven build session lifecycle.
 *
 * All callback methods (will) follow beforeXXX/afterXXX naming pattern to
 * indicate at what lifecycle point it is being called.
 *
 * @see <a href="https://maven.apache.org/examples/maven-3-lifecycle-extensions.html">example</a>
 * @see <a href="https://issues.apache.org/jira/browse/MNG-4224">MNG-4224</a>

                          Apache Maven

  What is it?
  -----------

  Maven is a software project management and comprehension tool. Based on
  the concept of a Project Object Model (POM), Maven can manage a project's
  build, reporting and documentation from a central piece of information.

  Documentation
  -------------

  The most up-to-date documentation can be found at https://maven.apache.org/.

  Release Notes
  -------------

    private static final String LS = System.lineSeparator();

    private Artifact artifact;

    // Needs to go away
    // These are really overrides now, projects defining dependencies for a plugin that override what is
    // specified in the plugin itself.
    private Set<Artifact> artifactDependencies;

    private ArtifactRepository localRepository;

    private List<ArtifactRepository> remoteRepositories;

        String id = artifact.getGroupId() + ":" + artifact.getArtifactId();

        boolean matched = false;
        for (Iterator<String> i = patterns.iterator(); i.hasNext() & !matched; ) {
            // TODO what about wildcards? Just specifying groups? versions?
            if (id.equals(i.next())) {
                matched = true;
            }
        }
        return matched;
    }

  .
  .
  .
</plugins>

We need this form so that the model builder can make the first pass at merging. Full merging cannot be done because we don't know what the version of the plugin is yet that the user has requested. For plugins in the default lifecycle they are typically defined in the plugin management section of the parent POM. When the merging is complete we are going to have something that looks like the following:

<plugins>
  <plugin>

    /**
     * Describes the source of an execution.
     */
    public enum Source {

        /**
         * An execution that originates from the direct invocation of a goal from the CLI.
         */
        CLI,

        /**
         * An execution that originates from a goal bound to a lifecycle phase.
         */
        LIFECYCLE,
    }

    private Source source = Source.LIFECYCLE;

    /**

   | it to several places.
   |
   | That repository definition will have a unique id, so we can create a mirror reference for that
   | repository, to be used as an alternate download site. The mirror site will be the preferred
   | server for that repository.
   |-->
  <mirrors>
    <!-- mirror
     | Specifies a repository mirror site to use instead of a given repository. The repository that