* @return The extracted descriptor or {@code null} if no descriptor was found.
     * @throws IOException If the descriptor is present but could not be parsed.
     */
    public ExtensionDescriptor build(File extensionJar) throws IOException {
        ExtensionDescriptor extensionDescriptor = null;

        if (extensionJar.isFile()) {

          <version>1.0.0/1.1.0</version>
          <type>String</type>
          <description>
            Flags this Mojo as requiring information about the dependencies that would make up the specified class
            path. As the name suggests, this is similar to requiresDependencyResolution and supports the same values.

     * If there's no such directory, an {@code IllegalStateException} will be thrown.
     *
     * @throws IllegalStateException if the root directory could not be found
     * @see #getTopDirectory()
     * @since 4.0.0
     */
    Path getRootDirectory();

    /**
     * @since 3.3.0
     */

                    .findFirst()
                    .orElseThrow(() -> new MavenExecutionException(
                            "Could not find project to resume reactor build from: " + selector + " vs "
                                    + formatProjects(projects),
                            request.getPom()));

            Toolchain identification information, which will be matched against project requirements.
            <p>For Maven 2.0.9 to 3.2.3, the actual content structure was completely open: each toolchain type would
            define its own format and semantics. This was generally a properties format.
            <p>Since Maven 3.2.4, the type for this field has been changed to Properties to match the de-facto
            format.

    private final ProjectsSelector projectsSelector = new DefaultProjectsSelector(projectBuilder);

    // Not using mocks for these strategies - a mock would just copy the actual implementation.

    private final ModelLocator modelLocator = new DefaultModelLocator();
    private final PomlessCollectionStrategy pomlessCollectionStrategy = new PomlessCollectionStrategy(projectBuilder);

 * <li>success with warnings - model field + non-error model problems
 * <li>error - no model, but diagnostics
 * <li>error - (partial) model and diagnostics
 * </ol>
 * Could encode these variants as subclasses, but kept in one for now
 *
 * @param <T> the model type
 */
public class Result<T> {

    /**
     * Success without warnings
     *
     * @param model
     */

          <association>
            <type>RepositoryPolicy</type>
          </association>
        </field>
      </fields>
      <!-- prevent Modello generation of an incorrect equals method. Could be avoided by using <identity/> tags to mark ID as the only identity field -->
      <codeSegments>
        <codeSegment>
          <version>1.0.0/1.1.0</version>
          <code>
            <![CDATA[
    /**

    <exportedArtifact>org.eclipse.aether:aether-connector-basic</exportedArtifact>

    <!--
      | NOTE: Don't exclude the wagons or any of their dependencies (apart from the wagon API). This would otherwise
      | provoke linkage errors for wagons contributed by build extensions. We also don't need to exclude the wagons

    /**
     * Gets the relative path for a locally installed artifact.
     * Note that the artifact need not actually exist yet at
     * the returned location, the path merely indicates where
     * the artifact would eventually be stored.
     *
     * @param session The session to use, must not be {@code null}.
     * @param artifact The artifact for which to determine the path, must not be {@code null}.