}

  @Override
  public Collection<V> removeAll(@Nullable Object key) {
    return MoreObjects.firstNonNull(asMap().remove(key), unmodifiableEmptyCollection());
  }

  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  Collection<V> unmodifiableEmptyCollection() {
    // These return false, rather than throwing a UOE, on remove calls.

    /**
     * Simulate a witness unregistration
     *
     * @param registrationId the registration ID to remove
     * @return true if registration was found and removed
     */
    public boolean unregisterWitness(String registrationId) {
        MockRegistration removed = registrations.remove(registrationId);
        if (removed != null) {
            log.debug("Mock unregistered witness: {}", registrationId);
            return true;

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemoveAllPropagatesToMultimap() {
    assertTrue(multimap().entries().removeAll(singleton(mapEntry(k0(), v0()))));
    expectMissing(mapEntry(k0(), v0()));
    assertEquals(getNumElements() - 1, multimap().size());
    assertFalse(multimap().containsEntry(k0(), v0()));
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  /*

        } finally {
          unlock();
        }
      }
    }

    /**
     * Removes an entry from within a table. All entries following the removed node can stay, but
     * all preceding ones need to be cloned.
     *
     * <p>This method does not decrement count for the removed entry, but does decrement count for

  }

  /**
   * Confirm that removeAll() returns a List that implements RandomAccess, even though get()
   * doesn't.
   */
  public void testRemoveAllRandomAccess() {
    Multimap<String, Integer> multimap = create();
    multimap.put("foo", 1);
    multimap.put("foo", 3);
    assertTrue(multimap.removeAll("foo") instanceof RandomAccess);
    assertTrue(multimap.removeAll("bar") instanceof RandomAccess);
  }

    }
  }

  private static Set<Feature<?>> computeReserializedCollectionFeatures(Set<Feature<?>> features) {
    Set<Feature<?>> derivedFeatures = new HashSet<>(features);
    derivedFeatures.remove(SERIALIZABLE);
    derivedFeatures.remove(SERIALIZABLE_INCLUDING_VIEWS);
    return derivedFeatures;
  }

    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));
    assertFalse(

    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));
    assertFalse(

      return delegate.poll();
    }

    @Override
    public E remove() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.remove();
    }

    @Override
    public boolean remove(Object object) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.remove(object);
    }

    @Override
    public @Nullable E peek() {

      K k = (K) key;
      return keyPredicate.apply(k);
    }
    return false;
  }

  @Override
  public Collection<V> removeAll(@Nullable Object key) {
    return containsKey(key) ? unfiltered.removeAll(key) : unmodifiableEmptyCollection();
  }

  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  Collection<V> unmodifiableEmptyCollection() {