*   called only once, just as it has its Executor.execute override called only once.)
       *
       * - if we return immediately from `execute` (in which case we never get here)
       *
       * - in the "reentrant submit" case of `execute` (in which case we must have started running a

        return 0;
      }
      if (lhs == null) {
        // lhs (null) comes just before justAfterNull.
        // If rhs is b, lhs comes first.
        if (rhs.equals(justAfterNull)) {
          return -1;
        }
        return justAfterNull.compareTo(rhs);
      }
      if (rhs == null) {
        // rhs (null) comes just before justAfterNull.
        // If lhs is b, rhs comes first.

        // copies/broadcasts. Other implicit copies may be supported eventually,
        // but need special handling for gradients (gradient of copy-on is not
        // just copy-off but includes a sum) and consideration of performance.
        //
        // TODO(allenl): There may be smarter ways to do this copy in some
        // cases, i.e. with a collective broadcast. We'll need to be careful

   */
  public static HashCode fromBytes(byte[] bytes) {
    checkArgument(bytes.length >= 1, "A HashCode must contain at least 1 byte.");
    return fromBytesNoCopy(bytes.clone());
  }

  /**
   * Creates a {@code HashCode} from a byte array. The array is <i>not</i> copied defensively, so it
   * must be handed-off so as to preserve the immutability contract of {@code HashCode}.
   */

   * process it; all should produce the same answer, the only difference should be the number of
   * process()/processRemaining() invocations, due to alignment.
   */
  @AndroidIncompatible // slow. TODO(cpovirk): Maybe just reduce iterations under Android.
  public void testExhaustive() throws Exception {
    Random random = new Random(0); // will iteratively make more debuggable, each time it breaks

   */
  public static HashCode fromBytes(byte[] bytes) {
    checkArgument(bytes.length >= 1, "A HashCode must contain at least 1 byte.");
    return fromBytesNoCopy(bytes.clone());
  }

  /**
   * Creates a {@code HashCode} from a byte array. The array is <i>not</i> copied defensively, so it
   * must be handed-off so as to preserve the immutability contract of {@code HashCode}.
   */

    HashTestUtils.assertInvariants(Hashing.fingerprint2011());
    assertEquals("Hashing.fingerprint2011()", Hashing.fingerprint2011().toString());
  }

  @AndroidIncompatible // slow TODO(cpovirk): Maybe just reduce iterations under Android.
  public void testGoodFastHash() {
    for (int i = 1; i < 200; i += 17) {
      HashFunction hasher = Hashing.goodFastHash(i);
      assertTrue(hasher.bits() >= i);

// keep.

// `value` must point to a string of length `length` bytes.
TF_CAPI_EXPORT extern void TF_SetAttrString(TF_OperationDescription* desc,
                                            const char* attr_name,
                                            const void* value, size_t length);
// `values` and `lengths` each must have lengths `num_values`.
// `values[i]` must point to a string of length `lengths[i]` bytes.

	// GetObjectNInfo returns a GetObjectReader that satisfies the
	// ReadCloser interface. The Close method runs any cleanup
	// functions, so it must always be called after reading till EOF
	//
	// IMPORTANTLY, when implementations return err != nil, this
	// function MUST NOT return a non-nil ReadCloser.

   * @throws NullPointerException if any element in the stream is {@code null}.
   * @return {@code Optional.of(onlyElement)} if the stream has exactly one element (must not be
   *     {@code null}) and returns {@code Optional.empty()} if it has none.
   */
  @SuppressWarnings("unchecked")
  public static <T> Collector<T, ?, Optional<T>> toOptional() {
    return (Collector) TO_OPTIONAL;