private static void addPhase(
            Graph graph, Graph.Vertex before, Graph.Vertex after, org.apache.maven.api.Lifecycle.Phase phase) {
        Graph.Vertex ep0 = graph.addVertex(BEFORE + phase.name());
        Graph.Vertex ep1 = graph.addVertex("$$" + phase.name());
        Graph.Vertex ep2 = graph.addVertex(phase.name());
        Graph.Vertex ep3 = graph.addVertex(AFTER + phase.name());
        graph.addEdge(ep0, ep1);

        ProjectDependencyGraph graph =
                new DefaultProjectDependencyGraph(Arrays.asList(aProject, bProject, cProject, dProject, eProject));
        graph = new FilteredProjectDependencyGraph(graph, Arrays.asList(aProject, dProject, eProject));
        final List<MavenProject> downstreamProjects = graph.getDownstreamProjects(aProject, false);
        assertEquals(2, downstreamProjects.size());

TF_Operation* Placeholder(TF_Graph* graph, TF_Status* s,
                          const char* name = "feed",
                          TF_DataType dtype = TF_INT32,
                          const std::vector<int64_t>& dims = {});

TF_Operation* Const(TF_Tensor* t, TF_Graph* graph, TF_Status* s,
                    const char* name = "const");

TF_Operation* ScalarConst(bool v, TF_Graph* graph, TF_Status* s,

import org.apache.maven.api.model.Parent;
import org.apache.maven.api.model.Plugin;
import org.apache.maven.artifact.ArtifactUtils;
import org.apache.maven.project.Graph.Vertex;

/**
 * ProjectSorter
 */
public class ProjectSorter {
    private Graph graph;

    private List<MavenProject> sortedProjects;

    private Map<String, MavenProject> projectMap;

    /**
     * Sort a list of projects.
     * <ul>

  // Verify that functions and their gradients are in host graph's GraphDef
  GraphDef gdef;
  GetGraphDef(host_graph_, &gdef);
  std::vector<std::pair<string, string>> grads = GetGradDefs(gdef);
  ASSERT_EQ(2, grads.size());
  ASSERT_EQ("FooFunc1", grads[0].first);
  ASSERT_EQ("MyGrad", grads[0].second);
  ASSERT_EQ("FooFunc2", grads[1].first);
  ASSERT_EQ("MyGrad", grads[1].second);

  TF_DeleteFunction(func1);

    /**
     *  null in dirty graph, actual
     *  scope for conflict-resolved graph
     */
    ArtifactScopeEnum scope;

    // ------------------------------------------------------------------------
    /**
     * init graph
     */
    public MetadataGraph(int nVertices) {
        init(nVertices, 2 * nVertices);
    }

    public MetadataGraph(int nVertices, int nEdges) {

         *       v3-v4
         *
         */
        v1 = graph.addVertex(new ArtifactMetadata("g", "a1", "1.0"));
        graph.setEntry(v1);
        v2 = graph.addVertex(new ArtifactMetadata("g", "a2", "1.0"));
        v3 = graph.addVertex(new ArtifactMetadata("g", "a3", "1.0"));
        v4 = graph.addVertex(new ArtifactMetadata("g", "a4", "1.0"));

        // v1-->v2
        graph.addEdge(v1, v2, new MetadataGraphEdge("1.1", true, null, null, 2, 1));

    this.allowsSelfLoops = allowsSelfLoops;
  }

  @Override
  public Graph<Integer> createGraph() {
    graphBuilder = GraphBuilder.undirected().allowsSelfLoops(allowsSelfLoops).immutable();
    return graphBuilder.build();
  }

  @Override
  final void addNode(Integer n) {
    graphBuilder.addNode(n);
    graph = graphBuilder.build();
  }

  @Override
  final void putEdge(Integer n1, Integer n2) {

         *   v1<
         *      v3-v4
         *
         */
        graph = new MetadataGraph(4, 3);
        v1 = graph.addVertex(new ArtifactMetadata("g", "a1", "1.0"));
        graph.setEntry(v1);
        v2 = graph.addVertex(new ArtifactMetadata("g", "a2", "1.0"));
        v3 = graph.addVertex(new ArtifactMetadata("g", "a3", "1.0"));
        v4 = graph.addVertex(new ArtifactMetadata("g", "a4", "1.0"));

        // v1-->v2

    /**
     * Construct a new value source, using the supplied object as the root from
     * which to start, and using expressions split at the dot ('.') to navigate
     * the object graph beneath this root.
     * @param root the root of the graph.
     */
    public ObjectBasedValueSource(Object root) {
        super(true);
        this.root = root;
    }

    /**