*/
  public MapJoiner withKeyValueSeparator(String keyValueSeparator) {
    return new MapJoiner(this, keyValueSeparator);
  }

  /**
   * An object that joins map entries in the same manner as {@code Joiner} joins iterables and
   * arrays. Like {@code Joiner}, it is thread-safe and immutable.
   *
   * <p>In addition to operating on {@code Map} instances, {@code MapJoiner} can operate on {@code

    for (int i = 0; i < ITERATIONS; i++) {
      long before = map.get(key);
      long result = map.addAndGet(key, addend);
      long after = map.get(key);
      assertEquals(before + addend, after);
      assertEquals(after, result);
      addend = after;
    }
    assertEquals(1, map.size());
    assertTrue(!map.isEmpty());
    assertTrue(map.containsKey(key));
  }

      builder.add(BEFORE_FIRST);
      builder.add(BEFORE_FIRST_2);
      builder.add(elements);
      builder.add(AFTER_LAST);
      builder.add(AFTER_LAST_2);
      return builder
          .build()
          .subSet(BEFORE_FIRST_2, AFTER_LAST_2)
          .asList()
          .subList(1, elements.length + 1);
    }
  }

  public abstract static class TestUnhashableSetGenerator

    CountingRunnable after = new CountingRunnable();

    future.addListener(before, directExecutor());
    future.setFuture(delegate);
    future.addListener(inBetween, directExecutor());
    delegate.set(1);
    future.addListener(after, directExecutor());

    before.assertRun();
    inBetween.assertRun();
    after.assertRun();
  }

   * #collectValueFromNonCancelledFuture}. As this is called after the subclass is constructed,
   * we're guaranteed to have properly initialized the subclass.
   */
  final void init() {
    /*
     * requireNonNull is safe because this is called from the constructor after `futures` is set but
     * before releaseResources could be called (because we have not yet set up any of the listeners

   * this graph.
   *
   * <p>This is equal to the union of {@link #predecessors(Object)} and {@link #successors(Object)}.
   *
   * <p>If {@code node} is removed from the graph after this method is called, the {@code Set}
   * {@code view} returned by this method will be invalidated, and will throw {@code
   * IllegalStateException} if it is accessed in any way, with the following exceptions:
   *

      }
      return message.toString();
    }
  }

  /**
   * Internal Lock implementations implement the {@code CycleDetectingLock} interface, allowing the
   * detection logic to treat all locks in the same manner.
   */
  private interface CycleDetectingLock {

    /** @return the {@link LockGraphNode} associated with this lock. */
    LockGraphNode getLockGraphNode();

  @SuppressWarnings("Immutable") // We don't modify this after construction.
  private final int[] rowCounts;

  @SuppressWarnings("Immutable") // We don't modify this after construction.
  private final int[] columnCounts;

  @SuppressWarnings("Immutable") // We don't modify this after construction.
  private final @Nullable V[][] values;

   *         .putAll('a', Arrays.asList('s', 'p', 'a', 'r', 'a', 'g', 'u', 's'))
   *         .putAll('c', Arrays.asList('h', 'e', 'r', 'r', 'y'))
   *         .build();
   *
   * // after deduplication, the resulting multimap is equivalent to
   *
   * static final ImmutableSetMultimap<Character, Character> FIRST_LETTER_MULTIMAP =
   *     ImmutableSetMultimap.<Character, Character>builder()

        // The trickled element is still after index.
        return new MoveDesc<>(actualLastElement, toTrickle);
      } else {
        // The trickled element is back before index, but the replaced element
        // has now been moved after index.
        return new MoveDesc<>(actualLastElement, changes.replaced);
      }
    }
    // Trickled element was after index to begin with, no adjustment needed.