if (session.getProjectDependencyGraph() != null || session.getProjects() != null) {
            ProjectDependencyGraph graph = new DefaultProjectDependencyGraph(session.getAllProjects());
            if (session.getProjects() != null) {
                graph = new FilteredProjectDependencyGraph(graph, session.getProjects());
            }

            result = Result.success(graph);
        }

    }

    List<Project> getProjects(List<org.apache.maven.project.MavenProject> projects);

    /**
     * May return null if the input project is null or is not part of the reactor.
     */
    @Nullable
    Project getProject(org.apache.maven.project.MavenProject project);

                return result;
            }

            result.setTopologicallySortedProjects(session.getProjects());

            result.setProject(session.getTopLevelProject());

            validatePrerequisitesForNonMavenPluginProjects(session.getProjects());

            validateRequiredProfiles(session, request.getProfileActivation());
            if (session.getResult().hasExceptions()) {

        when(projectStartedEvent1.getProject()).thenReturn(project1);
        ExecutionEvent projectStartedEvent2 = mock(ExecutionEvent.class);
        when(projectStartedEvent2.getProject()).thenReturn(project2);
        ExecutionEvent projectStartedEvent3 = mock(ExecutionEvent.class);
        when(projectStartedEvent3.getProject()).thenReturn(project3);

        // execute

            List<MavenProject> projects;

            if (taskSegment.isAggregating()) {
                projects = Collections.singletonList(rootProject);
            } else {
                projects = session.getProjects();
            }
            for (MavenProject project : projects) {
                ClassLoader tccl = Thread.currentThread().getContextClassLoader();
                MavenProject currentProject = session.getCurrentProject();

                    .getUpstreamProjects(projectBuild.getProject(), false)
                    .isEmpty()) {
                result.add(projectBuild.getProject());
            }
        }
        if (result.isEmpty() && !projectBuilds.isEmpty()) {
            // Must return at least one project
            result.add(projectBuilds.get(0).getProject());
        }

        return items.isEmpty();
    }

    /**
     * @return a set of all the projects managed by the build
     */
    public Set<MavenProject> getProjects() {
        return items.stream().map(ProjectSegment::getProject).collect(Collectors.toSet());
    }

            throws ExecutionException, InterruptedException {
        int nThreads = Math.min(
                session.getRequest().getDegreeOfConcurrency(),
                session.getProjects().size());
        boolean parallel = nThreads > 1;
        // Propagate the parallel flag to the root session and all the cloned sessions in each project segment
        session.setParallel(parallel);

 * <tr><td><code>reactorProjects</code></td>   <td></td>               <td>{@link MavenSession#getProjects()}</td></tr>
 * <tr><td><code>repositorySystemSession</code></td><td> (since Maven 3)</td>
 *                                             <td>{@link MavenSession#getRepositorySession()}</td></tr>

        InternalMavenSession mSession = InternalMavenSession.from(iSession);
        MavenSession session = mSession.getMavenSession();

        session.setProjects(projects);
        session.setAllProjects(session.getProjects());

        return session;
    }

    protected void initRepoSession(
            MavenExecutionRequest mavenExecutionRequest, ProjectBuildingRequest projectBuildingRequest)