* build a smaller set of projects but perform other operations in the context of your reactor.
     */
    private List<MavenProject> allProjects;

    private MavenProject topLevelProject;

    private ProjectDependencyGraph projectDependencyGraph;

    private boolean parallel;

    /**
     * Plugin context keyed by project ({@link MavenProject#getId()}) and by plugin lookup key

 * that the plugins/mojos can be used in arbitrary contexts. In particular, the mojos can be used for ordinary build
 * plugins as well as special purpose plugins like reports.
 *
 * @since 3.0
 */
@Named
@Singleton
public class DefaultMavenPluginManager implements MavenPluginManager {

    /**
     * <p>
     * PluginId =&gt; ExtensionRealmCache.CacheRecord map MavenProject context value key. The map is used to ensure the

import org.eclipse.aether.repository.RemoteRepository;

/**
 * Provides basic services to manage Maven plugins and their mojos. This component is kept general in its design such
 * that the plugins/mojos can be used in arbitrary contexts. In particular, the mojos can be used for ordinary build
 * plugins as well as special purpose plugins like reports.
 *
 * @since 3.0
 */
public interface MavenPluginManager {

    /**

        assertFileExistence(dir, filename, true);

        File file = new File(dir, filename);

        String contents = FileUtils.fileRead(file, encoding);

        assertEquals(contentsTest, contents);
    }

    public File createFile(File dir, String filename, String contents, String encoding) throws IOException {
        File file = new File(dir, filename);

        file.getParentFile().mkdirs();

    }

    /**
     * Simply converts the given content to an xml string.
     *
     * @param content the object to convert
     * @return the xml string representation
     * @throws XmlWriterException if an error occurs during the transformation
     * @see #fromXmlString(String)
     */
    public static String toXml(@Nonnull Model content) throws XmlWriterException {

    }

    /**
     * Simply converts the given content to an xml string.
     *
     * @param content the object to convert
     * @return the xml string representation
     * @throws XmlWriterException if an error occurs during the transformation
     * @see #fromXmlString(String)
     */
    public static String toXml(@Nonnull Model content) throws XmlWriterException {

    /**
     * Sets the value of the context value of this project identified by the given key. If the supplied value is
     * <code>null</code>, the context value is removed from this project. Context values are intended to allow core
     * extensions to associate derived state with project instances.
     */
    public void setContextValue(String key, Object value) {
        if (context == null) {
            context = new HashMap<>();

     * The returned list of versions is only dependent on the configured repositories and their contents.
     * The supplied request may also refer to a single concrete version rather than a version range.
     * In this case though, the result contains simply the (parsed) input version, regardless of the
     * repositories and their contents.
     *
     * @param artifact the artifact for which to resolve the versions

          documentation, if provided along with the Derivative Works; or,
          within a display generated by the Derivative Works, if and
          wherever such third-party notices normally appear. The contents
          of the NOTICE file are for informational purposes only and
          do not modify the License. You may add Your own attribution
          notices within Derivative Works that You distribute, alongside

        }

        boolean active = ensureAtLeastOneNonNull(os);

        String actualOsName = context.getSystemProperties().get("os.name").toLowerCase(Locale.ENGLISH);
        String actualOsArch = context.getSystemProperties().get("os.arch").toLowerCase(Locale.ENGLISH);
        String actualOsVersion = context.getSystemProperties().get("os.version").toLowerCase(Locale.ENGLISH);

        if (active && os.getFamily() != null) {