private <T extends Iterator<E>> void internalExecuteAndCompare(
      T reference, T target, IteratorOperation method) {
    Object referenceReturnValue = null;
    PermittedMetaException referenceException = null;
    Object targetReturnValue = null;
    Exception targetException = null;

    try {
      targetReturnValue = method.execute(target);
    } catch (Exception e) { // sneaky checked exception
      targetException = e;

                                if (resetArtifact.getVersion() == null && resetArtifact.getVersionRange() != null) {

                                    // go find the version. This is a total hack. See previous comment.
                                    List<ArtifactVersion> versions = resetArtifact.getAvailableVersions();
                                    if (versions == null) {
                                        try {

      return this;
    }

    @Override
    public Writer append(@CheckForNull CharSequence csq, int start, int end) {
      checkPositionIndexes(start, end, csq == null ? "null".length() : csq.length());
      return this;
    }

    @Override
    public Writer append(char c) {
      return this;
    }

    @Override
    public void flush() {}

  private <T extends Iterator<E>> void internalExecuteAndCompare(
      T reference, T target, IteratorOperation method) {
    Object referenceReturnValue = null;
    PermittedMetaException referenceException = null;
    Object targetReturnValue = null;
    Exception targetException = null;

    try {
      targetReturnValue = method.execute(target);
    } catch (Exception e) { // sneaky checked exception
      targetException = e;

     */
    if (result == null) {
      return null;
    } else {
      return (V) result;
    }
  }

  @CheckForNull
  static Object get(
      @CheckForNull Object hashTableObject,
      @Nullable Object[] alternatingKeysAndValues,
      int size,
      int keyOffset,
      @CheckForNull Object key) {
    if (key == null) {
      return null;
    } else if (size == 1) {

    Iterable<String> set = Sets.newHashSet("a", null, "b");
    assertTrue(FluentIterable.from(set).contains(null));
  }

  public void testContains_nullSetNo() {
    Iterable<String> set = ImmutableSortedSet.of("a", "b");
    assertFalse(FluentIterable.from(set).contains(null));
  }

  public void testContains_nullIterableYes() {
    Iterable<String> iterable = iterable("a", null, "b");

      queue[size] = null;
      return null;
    }
    E toTrickle = elementData(size);
    queue[size] = null;
    MoveDesc<E> changes = fillHole(index, toTrickle);
    if (lastElementAt < index) {
      // Last element is moved to before index, swapped with trickled element.
      if (changes == null) {
        // The trickled element is still after index.

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team member will apply `ready to pull` label to your change. This means we are
working on getting your pull request submitted to our internal repository. After
the change has been submitted internally, your pull request will be merged
automatically on GitHub.

If you want to contribute, start working through the TensorFlow codebase,

   * place....)
   */

  /**
   * Ensures that {@code reference} is non-null, throwing a {@code VerifyException} with a default
   * message otherwise.
   *
   * @return {@code reference}, guaranteed to be non-null, for convenience
   * @throws VerifyException if {@code reference} is {@code null}
   * @see Preconditions#checkNotNull Preconditions.checkNotNull()
   */
  @CanIgnoreReturnValue

Note that objects with `null` versions, i.e. objects created prior to enabling versioning break the immutability guarantees provided by versioning. When existing object replication is enabled, these objects will be replicated as `null` versions to the remote targets provided they are not present on the target or if `null` version of object on source is newer than the `null` version of object on target.