if (expectedSequenceNumber != ANY_SEQUENCE_NUMBER &&
      (entry == null || entry.sequenceNumber != expectedSequenceNumber)
    ) {
      return null // Snapshot is stale.
    }

    if (entry?.currentEditor != null) {
      return null // Another edit is in progress.
    }

    if (entry != null && entry.lockingSourceCount != 0) {
      return null // We can't write this file because a reader is still reading it.
    }

        // v1-->v2
        graph.addEdge(v1, v2, new MetadataGraphEdge("1.1", true, null, null, 2, 1));
        graph.addEdge(v1, v2, new MetadataGraphEdge("1.2", true, null, null, 2, 2));

        // v1-->v3
        graph.addEdge(v1, v3, new MetadataGraphEdge("1.1", true, null, null, 2, 1));
        graph.addEdge(v1, v3, new MetadataGraphEdge("1.2", true, null, null, 4, 2));

        // v3-->v4

    }

    @Override
    public int hashCode() {
        int hash = 17;
        hash = hash * 31 + (buildReactor == null ? 0 : buildReactor.hashCode());
        hash = hash * 31 + (ideWorkspace == null ? 0 : ideWorkspace.hashCode());
        hash = hash * 31 + (userLocalArtifactRepository == null ? 0 : userLocalArtifactRepository.hashCode());

        return hash;
    }

    @Override

        if (event == null) {
            return null;
        } else {
            String wagon = event.getWagon().getClass().getName();

            ArtifactTransferResource artifact = wrap(event.getWagon().getRepository(), event.getResource());

            ArtifactTransferEvent evt;
            if (event.getException() != null) {

     */
    @Deprecated
    default File locateExistingPom(File project) {
        Path path = locateExistingPom(project != null ? project.toPath() : null);
        return path != null ? path.toFile() : null;
    }

    /**
     * Returns the file containing the pom or null if a pom can not be found at the given file or in the given directory.
     *
     * @since 4.0.0
     */
    Path locateExistingPom(Path project);

        if (openJSSE != null) {
          return openJSSE
        }
      }

      // An Oracle JDK 9 like OpenJDK, or JDK 8 251+.
      val jdk9 = Jdk9Platform.buildIfSupported()

      if (jdk9 != null) {
        return jdk9
      }

      // An Oracle JDK 8 like OpenJDK, pre 251.
      val jdkWithJettyBoot = Jdk8WithJettyBootPlatform.buildIfSupported()

      if (jdkWithJettyBoot != null) {

        pageSize = getDefaultPageSize();
        currentPageNumber = getDefaultCurrentPageNumber();

        id = null;
        url = null;
        threadName = null;
        errorCount = null;
        lastAccessTime = null;
        errorCountMin = null;
        errorCountMax = null;
        errorName = null;

    }

    protected int getDefaultCurrentPageNumber() {
        return DEFAULT_CURRENT_PAGE_NUMBER;
    }

  internal var errorException: IOException? = null

  init {
    if (headers != null) {
      check(!isLocallyInitiated) { "locally-initiated streams shouldn't have headers yet" }
      headersQueue += headers
    } else {
      check(isLocallyInitiated) { "remotely-initiated streams should have headers" }
    }
  }

  /**
   * Returns true if this stream is open. A stream is open until either:

        while ((queuedTask = executingTaskQueue.nextTask) != null
            && (queuedExecutor = executingTaskQueue.nextExecutor) != null) {
          executingTaskQueue.nextTask = null;
          executingTaskQueue.nextExecutor = null;
          queuedExecutor.execute(queuedTask);
        }
      } finally {
        // Null out the thread field, so that we don't leak a reference to Thread, and so that

        if (url == null) {
            return null;
        }

        final FessConfig fessConfig = getFessConfig();
        String enc = Constants.UTF_8;
        if (StringUtil.isBlank(fessConfig.getCrawlerDocumentFileNameEncoding())) {
            final UrlQueue<?> urlQueue = CrawlingParameterUtil.getUrlQueue();
            if (urlQueue != null) {