* all elements that are contained by {@code set1} and not contained by {@code set2}. {@code set2}
   * may also contain elements not present in {@code set1}; these are simply ignored. The iteration
   * order of the returned set matches that of {@code set1}.
   *
   * <p>Results are undefined if {@code set1} and {@code set2} are sets based on different

        }

        //
        // TODO jvz Why isn't all this checking the job of the duty of the workspace resolver, we know that we
        // have a model that is suitable, yet more checks are done here and the one for the version is problematic
        // before because with parents as ranges it will never work in this scenario.
        //

        String groupId = getGroupId(candidateModel);

   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *
   * <p>This method is not type-safe, as it may be called on a map with keys that are not mutually
   * comparable.
   *
   * @throws ClassCastException if the keys in {@code map} are not mutually comparable
   * @throws NullPointerException if any key or value in {@code map} is null

   * nodes. This is an O(n) operation in the common case (and O(n^2) in the worst), but we are saved
   * by two things.
   *
   * <ul>
   *   <li>This is only called when a waiting thread times out or is interrupted. Both of which
   *       should be rare.
   *   <li>The waiters list should be very short.
   * </ul>
   */
  private void removeWaiter(Waiter node) {

        }

        ExecutorService createExecutor(int parallelism) {
            //
            // We need an executor that will not block.
            // We can't use work stealing, as we are building a graph
            // and this could lead to cycles where a thread waits for
            // a task to finish, then execute another one which waits
            // for the initial task...

        }
        return endOfData();
      }
    };
  }

  /**
   * Returns a view of {@code unfiltered} containing all elements that are of the type {@code
   * desiredType}.
   */
  @SuppressWarnings("unchecked") // can cast to <T> because non-Ts are removed
  @GwtIncompatible // Class.isInstance
  public static <T> UnmodifiableIterator<T> filter(Iterator<?> unfiltered, Class<T> desiredType) {

   * {@code factory}, and the multimap contents are all serializable.
   *
   * <p>The multimap is not threadsafe when any concurrent operations update the multimap, even if
   * {@code map} and the instances generated by {@code factory} are. Concurrent read operations will
   * work correctly. To allow concurrent update operations, wrap the multimap with a call to {@link

                        Severity.WARNING,
                        Version.BASE,
                        "parent.version",
                        null,
                        "is either LATEST or RELEASE (both of them are being deprecated)",
                        parent);
            }
        }

        if (request.getValidationLevel() >= ModelBuilderRequest.VALIDATION_LEVEL_MAVEN_2_0) {

    Iterator<List<Integer>> partitions = Iterators.partition(list.iterator(), 1);

    // Changes before the partition is retrieved are reflected
    list.set(0, 3);
    List<Integer> first = partitions.next();

    // Changes after are not
    list.set(0, 4);

    assertEquals(ImmutableList.of(3), first);
  }