Set<MavenProject> selectedProjects = new HashSet<>(requiredSelectors.size() + optionalSelectors.size());
            selectedProjects.addAll(
                    projectSelector.getRequiredProjectsBySelectors(request, allSortedProjects, requiredSelectors));
            selectedProjects.addAll(
                    projectSelector.getOptionalProjectsBySelectors(request, allSortedProjects, optionalSelectors));

 * required selectors.
 */
public final class ProjectSelector {
    private static final Logger LOGGER = LoggerFactory.getLogger(ProjectSelector.class);

    public Set<MavenProject> getRequiredProjectsBySelectors(
            MavenExecutionRequest request, List<MavenProject> projects, Set<String> projectSelectors)
            throws MavenExecutionException {
        Set<MavenProject> selectedProjects = new LinkedHashSet<>();