return AbstractNetwork.this.edges().size();
          }

          // Mostly safe: We check contains(u) before calling successors(u), so we perform unsafe
          // operations only in weird cases like checking for an EndpointPair<ArrayList> in a
          // Network<LinkedList>.
          @SuppressWarnings("unchecked")
          @Override
          public boolean contains(@CheckForNull Object obj) {

  }

  // We ought to be able to implement GenericDeclaration instead its parent AnnotatedElement.
  // That would give us this method declaration. But for some reason, implementing
  // GenericDeclaration leads to weird errors in Android tests:
  // IncompatibleClassChangeError: interface not implemented
  /** See {@link java.lang.reflect.GenericDeclaration#getTypeParameters()}. */
  public abstract TypeVariable<?>[] getTypeParameters();

    assertEquals(6, queue.size());
    assertEquals(8, queue.capacity());
    assertEquals(42, queue.maximumSize);
    assertSame(SOME_COMPARATOR, queue.comparator());
  }

  // TODO: tests that check the weird interplay between expected size,
  // maximum size, size of initial contents, default capacity...

  private static void checkNatural(MinMaxPriorityQueue<Integer> queue) {

          return null;
        }
      }
      return topMetaIterator;
    }

    @Override
    public boolean hasNext() {
      while (!checkNotNull(iterator).hasNext()) {
        // this weird checkNotNull positioning appears required by our tests, which expect
        // both hasNext and next to throw NPE if an input iterator is null.

        topMetaIterator = getTopMetaIterator();