/*
         *       v2
         *   v1<
         *       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"));

            res.setVersionedVertices(false);
            res.setScopedVertices(false);

            MetadataGraphVertex resEntry = res.addVertex(entry.getMd());
            res.setEntry(resEntry);

            res.setScope(requestedScope);

            for (MetadataGraphVertex v : vertices) {
                final List<MetadataGraphEdge> ins = graph.getIncidentEdges(v);

         *       v2
         *   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"));

  }

  @Override
  Entry<E> getEntry(int index) {
    return Multisets.immutableEntry(elementSet.asList().get(index), getCount(index));
  }

  @Override
  @CheckForNull
  public Entry<E> firstEntry() {
    return isEmpty() ? null : getEntry(0);
  }

  @Override
  @CheckForNull
  public Entry<E> lastEntry() {
    return isEmpty() ? null : getEntry(length - 1);
  }

  @Override

        list.addLast("1");
        list.addLast("2");
        list.addLast("3");
        assertThat(list.getEntry(0).getElement(), is("1"));
        assertThat(list.getEntry(1).getElement(), is("2"));
        assertThat(list.getEntry(2).getElement(), is("3"));
        try {
            list.getEntry(-1);
            fail();
        } catch (final ClIndexOutOfBoundsException ex) {
            System.out.println(ex);

                // single entry in the classpath, populated from itself
                ArtifactMetadata amd = cleanGraph.getEntry().getMd();
                cpc.add(amd);
            } else {
                ClasspathGraphVisitor v = new ClasspathGraphVisitor(cleanGraph, cpc);
                MetadataGraphVertex entry = cleanGraph.getEntry();
                // entry point
                v.visit(entry);
            }

            return cpc;

    @J2ktIncompatible // serialization
    @GwtIncompatible // serialization
    Object writeReplace() {
      return super.writeReplace();
    }
  }

  @Override
  Entry<E> getEntry(int index) {
    return contents.getEntry(index);
  }

  @GwtIncompatible
  private static class SerializedForm implements Serializable {
    final Object[] elements;
    final int[] counts;

  @Override
  public int size() {
    return forward.size();
  }

  @Override
  public ImmutableSortedSet<E> elementSet() {
    return forward.elementSet().descendingSet();
  }

  @Override
  Entry<E> getEntry(int index) {
    return forward.entrySet().asList().reverse().get(index);
  }

  @Override
  public ImmutableSortedMultiset<E> descendingMultiset() {
    return forward;
  }

  @Override

  public int count(@Nullable Object element) {
    throw new AssertionError();
  }

  @Override
  public ImmutableSet<E> elementSet() {
    throw new AssertionError();
  }

  @Override
  Entry<E> getEntry(int index) {
    throw new AssertionError();
  }

  @Override
  boolean isPartialView() {
    throw new AssertionError();
  }

  @Override
  public int size() {
    throw new AssertionError();
  }

     * @param scope - which classpath to extract
     * @param resolve - whether to resolve artifacts.
     * @return Collection of metadata objects in the linked subgraph of the graph which
     *             contains the graph.getEntry() vertice
     */
    ClasspathContainer transform(MetadataGraph dirtyGraph, ArtifactScopeEnum scope, boolean resolve)
            throws MetadataGraphTransformationException;