* unprefixed expressions.
         * @param possiblePrefixes The possible prefixes.
         * @param root The root of the graph.
         * @param allowUnprefixedExpressions if we allow undefined expressions or not.
         */
        public PrefixedObjectValueSource(
                List<String> possiblePrefixes, Object root, boolean allowUnprefixedExpressions) {

            FOR INTERNAL USE ONLY. This is a unique identifier assigned to each
            resource to allow Maven to merge changes to this resource that take
            place during the execution of a plugin. This field must be managed
            by the generated parser and formatter classes in order to allow it
            to survive model interpolation.
          </description>
          <type>String</type>

     * during metadata retrieval.
     */
    int VALIDATION_LEVEL_MINIMAL = 0;

    /**
     * Denotes validation as performed by Maven 2.0. This validation level is meant as a compatibility mode to allow
     * users to migrate their projects.
     */
    int VALIDATION_LEVEL_MAVEN_2_0 = 20;

    /**
     * Denotes validation as performed by Maven 3.0. This validation level is meant for existing projects.
     */

          <description>
            The configurator type to use when injecting parameter values into this Mojo. The value is normally deduced
            from the Mojo's implementation language, but can be specified to allow a custom ComponentConfigurator
            implementation to be used.
          </description>
        </field>
        <field>
          <name>composer</name>
          <version>1.0.0/1.1.0</version>

 *
 * As a non-default component this now gets a negative priority relative to other implementations
 * of the same interface. Since we want to allow overriding this doesn't matter in this case.
 * (if it did we could add @Priority of 0 to match the priority given to default components.)
 */
@Named
@Singleton
public class DefaultModelProcessor implements ModelProcessor {

    private List<String> pluginGroups;

    private boolean isProjectPresent = true;

    // ----------------------------------------------------------------------------
    // We need to allow per execution user and global settings as the embedder
    // might be running in a mode where it's executing many threads with totally
    // different settings.

                    Severity.ERROR,
                    Version.V20,
                    repository.getUrl(),
                    null,
                    repository)) {
                // only allow ${basedir} and ${project.basedir}
                Matcher m = EXPRESSION_NAME_PATTERN.matcher(repository.getUrl());
                while (m.find()) {

                                e);
            }

            projectBuildingHelper.selectProjectRealm(project);
        }

        // build the regular repos after extensions are loaded to allow for custom layouts
        try {
            remoteRepositories = projectBuildingHelper.createArtifactRepositories(
                    model.getRepositories(), remoteRepositories, projectBuildingRequest);

        }
    }

    /**
     * Ensures the last updated timestamp of the specified metadata does not refer to the future and fixes the local
     * metadata if necessary to allow proper merging/updating of metadata during deployment.
     */
    private void fixTimestamp(File metadataFile, Metadata metadata, Metadata reference) {
        boolean changed = false;