// TODO(kevinb): use Hashing/move this to Hashing?
    h += (h << 15) ^ 0xffffcd7d;
    h ^= (h >>> 10);
    h += (h << 3);
    h ^= (h >>> 6);
    h += (h << 2) + (h << 14);
    return h ^ (h >>> 16);
  }

  /**
   * This method is a convenience for testing. Code should call {@link Segment#newEntry} directly.
   */
  @VisibleForTesting

    assertEquals(12, multiset.add(KEY, 3));
    assertEquals(15, existing.get());
  }

  public void testRemove_zeroFromSome() {
    final int INITIAL_COUNT = 14;
    when(backingMap.get(KEY)).thenReturn(new AtomicInteger(INITIAL_COUNT));

    assertEquals(INITIAL_COUNT, multiset.remove(KEY, 0));
  }

  public void testRemove_zeroFromNone() {

    testRotate(new float[] {0, 1, 2, 3, 4, 5, 6}, 5, 1, 6, new float[] {0, 1, 2, 3, 4, 5, 6});
    testRotate(new float[] {0, 1, 2, 3, 4, 5, 6}, 14, 1, 6, new float[] {0, 2, 3, 4, 5, 1, 6});

    // Rotate the first three elements
    testRotate(new float[] {0, 1, 2, 3, 4, 5, 6}, -2, 0, 3, new float[] {2, 0, 1, 3, 4, 5, 6});

    testRotate(new int[] {0, 1, 2, 3, 4, 5, 6}, 0, 1, 6, new int[] {0, 1, 2, 3, 4, 5, 6});
    testRotate(new int[] {0, 1, 2, 3, 4, 5, 6}, 5, 1, 6, new int[] {0, 1, 2, 3, 4, 5, 6});
    testRotate(new int[] {0, 1, 2, 3, 4, 5, 6}, 14, 1, 6, new int[] {0, 2, 3, 4, 5, 1, 6});

    // Rotate the first three elements
    testRotate(new int[] {0, 1, 2, 3, 4, 5, 6}, -2, 0, 3, new int[] {2, 0, 1, 3, 4, 5, 6});

        5,
        1,
        6,
        new char[] {'0', '1', '2', '3', '4', '5', '6'});
    testRotate(
        new char[] {'0', '1', '2', '3', '4', '5', '6'},
        14,
        1,
        6,
        new char[] {'0', '2', '3', '4', '5', '1', '6'});

    // Rotate the first three elements
    testRotate(
        new char[] {'0', '1', '2', '3', '4', '5', '6'},
        -2,