queue[size] = null;
      return null;
    }
    E toTrickle = elementData(size);
    queue[size] = null;
    MoveDesc<E> changes = fillHole(index, toTrickle);
    if (lastElementAt < index) {
      // Last element is moved to before index, swapped with trickled element.
      if (changes == null) {
        // The trickled element is still after index.

        this.servers = (servers != null) ? servers : new ArrayList<>();
        this.proxies = (proxies != null) ? proxies : new ArrayList<>();
        this.problems = (problems != null) ? problems : new ArrayList<>();
    }

    @Override
    public Server getServer() {
        return servers.isEmpty() ? null : servers.get(0);
    }

    @Override
    public List<Server> getServers() {

 * NullPointerException} or {@link UnsupportedOperationException} whenever null is passed to a
 * parameter whose declaration or type isn't annotated with an annotation with the simple name
 * {@code Nullable}, {@code CheckForNull}, {@code NullableType}, or {@code NullableDecl}.
 *
 * <p>The tested methods and constructors are invoked -- each time with one parameter being null and
 * the rest not null -- and the test fails if no expected exception is thrown. {@code

    Map<C, V> row = safeGet(rowMap(), rowKey);
    return row != null && Maps.safeContainsKey(row, columnKey);
  }

  @Override
  public @Nullable V get(@Nullable Object rowKey, @Nullable Object columnKey) {
    Map<C, V> row = safeGet(rowMap(), rowKey);
    return (row == null) ? null : safeGet(row, columnKey);
  }

  @Override
  public boolean isEmpty() {
    return size() == 0;
  }

     *
     * @param key the key under which to store the session data, must not be {@code null}
     * @param oldValue the expected data currently associated with the key, may be {@code null}
     * @param newValue the data to associate with the key, may be {@code null} to remove the mapping
     * @return {@code true} if the key mapping was successfully updated from the old value to the new value,

    private @Nullable EnumSet<E> set;

    void add(E e) {
      if (set == null) {
        set = EnumSet.of(e);
      } else {
        set.add(e);
      }
    }

    EnumSetAccumulator<E> combine(EnumSetAccumulator<E> other) {
      if (this.set == null) {
        return other;
      } else if (other.set == null) {
        return this;
      } else {
        this.set.addAll(other.set);

    notEqualObject1 = new ValidTestObject(0, 2);
  }

  /** Test null reference yields error */
  public void testAddNullReference() {
    assertThrows(NullPointerException.class, () -> equalsTester.addEqualityGroup((Object) null));
  }

  /** Test equalObjects after adding multiple instances at once with a null */
  public void testAddTwoEqualObjectsAtOnceWithNull() {
    assertThrows(

                null,
                dependency.getType()));
    }

    @Nonnull
    default DependencyCoordinates create(@Nonnull Session session, Plugin plugin) {
        // TODO: hard coded string
        return create(DependencyCoordinatesFactoryRequest.build(
                session, plugin.getGroupId(), plugin.getArtifactId(), plugin.getVersion(), null, null, "maven-plugin"));
    }

    @Nonnull

    @Test
    void testVersionlessManagedDependency() throws Exception {
        File pomFile = new File("src/test/resources/projects/versionless-managed-dependency.xml");
        MavenSession mavenSession = createMavenSession(null);
        ProjectBuildingRequest configuration = new DefaultProjectBuildingRequest();
        configuration.setRepositorySession(mavenSession.getRepositorySession());

        // Intentionally notNull because Super POM may not contain a modelId
        Objects.requireNonNull(modelId, "modelId cannot null");

        if (activeProfiles != null) {
            this.activePomProfiles.put(modelId, new ArrayList<>(activeProfiles));
        } else {
            this.activePomProfiles.remove(modelId);
        }

        return this;