@CheckForNull private 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);

            ssn.getSmbTree( LOGON_SHARE, null ).treeConnect( null, null );
        }
        return new NtlmChallenge( trans.server.encryptionKey, dc );
    }
    public static NtlmChallenge getChallengeForDomain()
                throws SmbException, UnknownHostException {
        if( DOMAIN == null ) {
            throw new SmbException( "A domain was not specified" );
        }

    require(parameter != null) {
      "Parameter is not formatted correctly: \"${substring(s)}\" for: \"$this\""
    }

    val name = parameter.groups[1]?.value
    if (name == null) {
      s = parameter.range.last + 1
      continue
    }

    val token = parameter.groups[2]?.value
    val value =
      when {
        token == null -> {

    } catch (RuntimeException tolerated) {
      // GWT's TreeMap.entrySet().removeAll(null) doesn't throws NPE.
    }
  }

  @Override
  public void testEntrySetRetainAllNullFromEmpty() {
    try {
      super.testEntrySetRetainAllNullFromEmpty();
    } catch (RuntimeException tolerated) {
      // GWT's TreeMap.entrySet().retainAll(null) doesn't throws NPE.
    }
  }

  @Override

        final MethodDesc methodDesc = beanDesc.getMethodDescNoException(name);
        if (methodDesc == null) {
            return null;
        }
        final Object value = methodDesc.invoke(annotation);
        if (value == null || "".equals(value)) {
            return null;
        }
        return value;
    }

     *
     * @param session The session to use, must not be {@code null}.
     * @param local The local repository, must not be {@code null}.
     * @param artifact The artifact for which to determine the path, must not be {@code null}.
     * @param remote – The source repository of the artifact, must not be {@code null}.
     * @return The path, relative to the local repository's base directory.
     */
    @Nonnull

public interface VersionParser extends Service {

    /**
     * Parses the specified version string, for example "1.0".
     *
     * @param version the version string to parse, must not be {@code null}
     * @return the parsed version, never {@code null}
     * @throws VersionParserException if the string violates the syntax rules of this scheme
     * @see org.apache.maven.api.Session#parseVersion(String)
     */
    @Nonnull

     *
     * @param model The model whose duplicate elements should be merged, must not be {@code null}.
     * @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 mergeDuplicates(Model model, ModelBuildingRequest request, ModelProblemCollector problems);

    /**

    initCollectionWithNullElement();
    expectReturnsTrue(disjoint);
    expectContents();
  }

  // retainAll(null)

  /*
   * AbstractCollection fails the retainAll(null) test when the subject
   * collection is empty, but we'd still like to test retainAll(null) when we
   * can. We split the test into empty and non-empty cases. This allows us to
   * suppress only the former.
   */

    e: IOException,
  ) {
    responses.add(RecordedResponse(call.request(), null, null, null, e))
    (this as Object).notifyAll()
  }

  @Synchronized
  override fun onResponse(
    call: Call,
    response: Response,
  ) {
    val body = response.body.string()
    responses.add(RecordedResponse(call.request(), response, null, body, null))
    (this as Object).notifyAll()
  }

  /**