final List<Vertex> children = new ArrayList<>();
        final List<Vertex> parents = new ArrayList<>();

        Vertex(String label) {
            this.label = label;
        }

        String getLabel() {
            return label;
        }

        List<Vertex> getChildren() {
            return children;
        }

        List<Vertex> getParents() {
            return parents;
        }

      fail("transformed list iterator is addable");
    } catch (UnsupportedOperationException | IllegalStateException expected) {
    }
    try {
      iterator.set("1");
      fail("transformed list iterator is settable");
    } catch (UnsupportedOperationException | IllegalStateException expected) {
    }
  }

  public void testTransformIteratorRandomAccess() {
    List<Integer> fromList = Lists.newArrayList(SOME_LIST);

      fail("transformed list iterator is addable");
    } catch (UnsupportedOperationException | IllegalStateException expected) {
    }
    try {
      iterator.set("1");
      fail("transformed list iterator is settable");
    } catch (UnsupportedOperationException | IllegalStateException expected) {
    }
  }

  public void testTransformIteratorRandomAccess() {
    List<Integer> fromList = Lists.newArrayList(SOME_LIST);