*     iterator().next()} or {@link Iterables#getFirst} instead.
   */
  @SuppressWarnings("nullness") // Unsafe, but we can't do much about it now.
  public final Optional<@NonNull E> first() {
    Iterator<E> iterator = getDelegate().iterator();
    return iterator.hasNext() ? Optional.of(iterator.next()) : Optional.absent();
  }

  /**

		t.Fatal(err)
	}

	var nextFiles []string
	if v := runtime.Version(); strings.Contains(v, "devel") || strings.Contains(v, "beta") {
		next, err := filepath.Glob(filepath.Join(testenv.GOROOT(t), "api/next/*.txt"))
		if err != nil {
			t.Fatal(err)
		}
		nextFiles = next
	}

	for _, c := range contexts {
		c.Compiler = build.Default.Compiler
	}

	walkers := make([]*Walker, len(contexts))

        DfsReferralDataInternal mockReferral = mock(DfsReferralDataInternal.class);
        when(mockReferral.getPathConsumed()).thenReturn(15); // e.g., "\\\\server\\share".length()
        when(mockReferral.next()).thenReturn(mockReferral); // Simple loop for the do-while
        assertDoesNotThrow(() -> dfsImpl.cache(mockContext, "\\\\server\\share\\path", mockReferral));
    }

   * us to tell immediately (see tryAcquire(timeout)) whether a particular timeout is enough to get
   * us to the point of the next scheduling time, since we always maintain that. And what we mean by
   * "an unused RateLimiter" is also defined by that notion: when we observe that the
   * "expected arrival time of the next request" is actually in the past, then the difference (now -

 *
 * Each derivation can capture the next value or any intermediate objects for later closing.
 *
 * <p>A step can be the input to at most one derived step. Once you transform its value, catch its
 * exception, or combine it with others, you cannot do anything else with it, including declare it
 * to be the last step of the pipeline.
 *
 * <h4>Transforming</h4>
 *

    }
    
    @Override
    public void encode(byte[] buffer, int offset) {
        // Context header
        int nameLen = getName().length();
        writeInt4(buffer, offset, 16);  // Next
        writeInt2(buffer, offset + 4, nameLen);  // NameOffset
        writeInt2(buffer, offset + 6, nameLen);  // NameLength
        writeInt2(buffer, offset + 8, 0);  // Reserved

      val openClientSocket = openClientSockets.iterator()
      while (openClientSocket.hasNext()) {
        openClientSocket.next().closeQuietly()
        openClientSocket.remove()
      }

      val httpConnection = openConnections.iterator()
      while (httpConnection.hasNext()) {
        httpConnection.next().closeQuietly()
        httpConnection.remove()
      }
      dispatcher.close()
    }
  }

                    Iterator<Item> right = ((ListItem) item).iterator();

                    while (left.hasNext() || right.hasNext()) {
                        Item l = left.hasNext() ? left.next() : null;
                        Item r = right.hasNext() ? right.next() : null;

                        // if this is shorter, then invert the compare and mul with -1

	if err != nil {
		t.Errorf("No error should happen, got %v", err)
	}

	type Result struct {
		Name string
		Age  int
	}

	var results []Result
	for rows.Next() {
		var result Result
		if err := DB.ScanRows(rows, &result); err != nil {
			t.Errorf("should get no error, but got %v", err)
		}
		results = append(results, result)
	}

  public void testKeysEntrySetIteratorRemove() {
    Multiset<K> keys = multimap().keys();
    Iterator<Multiset.Entry<K>> itr = keys.entrySet().iterator();
    assertEquals(Multisets.immutableEntry(k0(), 1), itr.next());
    itr.remove();
    assertTrue(multimap().isEmpty());
  }

  @CollectionSize.Require(SEVERAL)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testKeysEntrySetRemove() {