synchronized (mutex) {
        Collection<V> collection = super.get(key);
        return (collection == null) ? null : typePreservingCollection(collection, mutex);
      }
    }

    @Override
    public Set<Map.Entry<K, Collection<V>>> entrySet() {
      synchronized (mutex) {
        if (asMapEntrySet == null) {
          asMapEntrySet = new SynchronizedAsMapEntries<>(delegate().entrySet(), mutex);
        }

    waiter1.join();
    waiter2.awaitWaiting(); // should still be blocked

    LockSupport.unpark(waiter2); // spurious wakeup
    waiter2.awaitWaiting(); // should eventually re-park

    future.set(null);
    waiter2.join();
  }

  public void testRemoveWaiter_polling() throws Exception {
    final AbstractFuture<String> future = new AbstractFuture<String>() {};
    WaiterThread waiter = new WaiterThread(future);

    assertThrows(
        NullPointerException.class, () -> builder.put(immutableCell((Character) null, 1, "foo")));
    assertThrows(
        NullPointerException.class, () -> builder.put(immutableCell('a', (Integer) null, "foo")));
    assertThrows(
        NullPointerException.class, () -> builder.put(immutableCell('a', 1, (String) null)));
  }

  private static class StringHolder {
    @Nullable String string;
  }

            if (uploadFile == null) {
                throwValidationError(messages -> messages.addErrorsDesignFileNameIsNotFound("designFileName"), this::asListHtml);
                return null;
            }
        } else {
            throwValidationError(messages -> messages.addErrorsDesignFileIsUnsupportedType("designFileName"), this::asListHtml);
            return null;
        }

    for (Listener listener : listeners) {
      listener.execute();
    }
    listeners = null;
  }

  protected void afterDone() {}

  @Override
  protected final Throwable tryInternalFastPathGetFailure() {
    if (this instanceof Trusted) {
      return state == State.FAILURE ? throwable : null;
    }
    return null;
  }

  final void maybePropagateCancellationTo(@Nullable Future<?> related) {

        assertEquals("1test user", sambaHelper.getAccountId(USER_SID));

    }

    private static final SID USER_SID = new SID() {

        @Override
        public SID getDomainSid() {
            return null;
        }

        @Override
        public int getRid() {
            return 0;
        }

        @Override
        public String toDisplayString() {

    }

    @Override
    protected Map<String, Object> createTestParam(int id) {
        fail(); // Unreachable
        return null;
    }

    @Override
    protected Map<String, Object> getUpdateMap() {
        fail(); // Unreachable
        return null;
    }

    @Override
    protected void testRead() {
        final Map<String, Object> searchBody = new HashMap<>();

                    request.getArtifact(),
                    request.getRemoteRepositories());
        }
    }

    private static <T> List<T> toList(Collection<T> items) {
        return (items != null) ? new ArrayList<>(items) : null;
    }

     */
    int getCharacterOffset();

    /**
     * Returns the public ID of the XML
     * @return the public ID, or null if not available
     */
    String getPublicId();

    /**
     * Returns the system ID of the XML
     * @return the system ID, or null if not available
     */
    String getSystemId();

     *            be <code>null</code>.
     * @param request The model building request that holds further settings, must not be {@code null}.
     * @param problems The container used to collect problems that were encountered, must not be {@code null}.
     */
    void injectManagement(Model model, ModelBuildingRequest request, ModelProblemCollector problems);