public void testOffer_nullSupported() {
    assertTrue("offer(null) should return true", getQueue().offer(null));
    expectAdded((E) null);
  }

  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
  public void testOffer_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> getQueue().offer(null));
    expectUnchanged();

        if (activation == null) {
            return false;
        }

        ActivationProperty property = activation.getProperty();

        if (property == null) {
            return false;
        }

        String name = property.getName();
        boolean reverseName = false;

        if (name != null && name.startsWith("!")) {
            reverseName = true;

        if (kid == null) {
            return;
        }

        if (children == null) {
            children = new MetadataTreeNode[nChildren];
        }

        children[index % nChildren] = kid;
    }

    // ------------------------------------------------------------------
    @Override
    public String toString() {
        return md == null ? "no metadata" : md.toString();
    }

     * @return The property, or null if no such property exists.
     */
    public PropertyMetaData findProperty(String name) {
        PropertyMetaData propertyMetaData = declaredProperties.get(name);
        if (propertyMetaData != null) {
            return propertyMetaData;
        }
        ClassMetaData superClass = getSuperClass();
        if (superClass != null) {
            return superClass.findProperty(name);

     * created automatically.
     *
     * @param output The file to serialize the model to, must not be {@code null}.
     * @param options The options to use for serialization, may be {@code null} to use the default values.
     * @param model The model to serialize, must not be {@code null}.
     * @throws IOException If the model could not be serialized.
     */

     *            plugin repositories.
     * @return This request, never {@code null}.
     */
    PluginVersionRequest setPom(Model pom);

    /**
     * Gets the remote repositories to use.
     *
     * @return The remote repositories to use, never {@code null}.
     */
    List<RemoteRepository> getRepositories();

    /**

     *
     * @param input The reader to deserialize the model from, must not be {@code null}.
     * @param options The options to use for deserialization, may be {@code null} to use the default values.
     * @return The deserialized model, never {@code null}.
     * @throws IOException If the model could not be deserialized.
     * @throws ModelParseException If the input format could not be parsed.
     */

        fun store(data: Map<String, Any>, file: File, comment: String? = null) {
            store(propertiesFrom(data), file, comment)
        }

        /**
         * Writes [Properties] to a file, but without including the timestamp comment.
         *
         * See [PropertiesUtils.store].
         */
        fun store(properties: Properties, file: File, comment: String? = null) {

        requireNonNull(artifact, "artifact cannot be null");
        Model model = null;

        for (WorkspaceReader workspaceReader : readers) {
            if (workspaceReader instanceof MavenWorkspaceReader mavenWorkspaceReader) {
                model = mavenWorkspaceReader.findModel(artifact);
                if (model != null) {
                    break;
                }
            }
        }

            if (existingCall != null) enqueuedCall.reuseCallsPerHostFrom(existingCall)
          }
        }

        val becameIdle =
          (finishedCall != null || finishedAsyncCall != null) &&
            (executorIsShutdown || runningAsyncCalls.isEmpty()) &&
            runningSyncCalls.isEmpty()
        val idleCallbackToRun = if (becameIdle) idleCallback else null

        if (executorIsShutdown) {