assertThrows(NullPointerException.class, () -> ImmutableSortedMultiset.copyOf(iterator));
  }

  private static class CountingIterable implements Iterable<String> {
    int count = 0;

    @Override
    public Iterator<String> iterator() {
      count++;
      return asList("a", "b", "a").iterator();
    }
  }

  public void testCopyOf_plainIterable() {
    CountingIterable iterable = new CountingIterable();

    assertThrows(NullPointerException.class, () -> ImmutableSortedMultiset.copyOf(iterator));
  }

  private static class CountingIterable implements Iterable<String> {
    int count = 0;

    @Override
    public Iterator<String> iterator() {
      count++;
      return asList("a", "b", "a").iterator();
    }
  }

  public void testCopyOf_plainIterable() {
    CountingIterable iterable = new CountingIterable();

    Comparator<Object> valueComparator = (Comparator<Object>) stream.readObject();
    int keyCount = stream.readInt();
    if (keyCount < 0) {
      throw new InvalidObjectException("Invalid key count " + keyCount);
    }
    ImmutableMap.Builder<Object, ImmutableSet<Object>> builder = ImmutableMap.builder();
    int tmpSize = 0;

    for (int i = 0; i < keyCount; i++) {

   *
   * <p><b>Java 8+ users:</b> In most cases, the {@code Stream} equivalent of this method is {@code
   * stream.filter(element::equals).count()}. If {@code element} might be null, use {@code
   * stream.filter(Predicate.isEqual(element)).count()} instead.
   *
   * @see java.util.Collections#frequency(Collection, Object) Collections.frequency(Collection,
   *     Object)
   */

   * becomes {@code count}.
   *
   * @return the count of {@code element} in the multiset before this call
   * @throws IllegalArgumentException if {@code count} is negative
   */
  @CanIgnoreReturnValue
  @Override
  public int setCount(E element, int count) {
    checkNotNull(element);
    checkNonnegative(count, "count");
    while (true) {

    // no entry
    assertEquals(0, segment.count);
    assertNull(segment.remove(key, hash));
    assertEquals(0, segment.count);

    // same key
    table.set(index, entry);
    segment.count++;
    assertEquals(1, segment.count);
    assertSame(oldValue, segment.get(key, hash));
    assertSame(oldValue, segment.remove(key, hash));
    assertEquals(0, segment.count);
    assertNull(segment.get(key, hash));

    // no entry
    assertEquals(0, segment.count);
    assertNull(segment.remove(key, hash));
    assertEquals(0, segment.count);

    // same key
    table.set(index, entry);
    segment.count++;
    assertEquals(1, segment.count);
    assertSame(oldValue, segment.get(key, hash));
    assertSame(oldValue, segment.remove(key, hash));
    assertEquals(0, segment.count);
    assertNull(segment.get(key, hash));

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().remove(e0(), 0));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testRemove_occurrences_present() {
    assertEquals(
        "multiset.remove(present, 2) didn't return the old count",
        1,
        getMultiset().remove(e0(), 2));

                setValue(e, key, value, now);
                newCount = this.count; // count remains unchanged
              } else {
                setValue(e, key, value, now);
                newCount = this.count + 1;
              }
              this.count = newCount; // write-volatile
              evictEntries(e);
              return null;

      fail();
    } catch (NullPointerException expected) {
    }
  }

  private static class CountingIterable implements Iterable<String> {
    int count = 0;

    @Override
    public Iterator<String> iterator() {
      count++;
      return asList("a", "b", "a").iterator();
    }
  }

  public void testCopyOf_plainIterable() {
    CountingIterable iterable = new CountingIterable();